Selenium in edible mushrooms.

Science.gov (United States)

Falandysz, Jerzy

2008-01-01

Selenium is vital to human health. This article is a compendium of virtually all the published data on total selenium concentrations, its distribution in fruitbody, bioconcentration factors, and chemical forms in wild-grown, cultivated, and selenium-enriched mushrooms worldwide. Of the 190 species reviewed (belonging to 21 families and 56 genera), most are considered edible, and a few selected data relate to inedible mushrooms. Most of edible mushroom species examined until now are selenium-poor (cesarea, A. campestris, A. edulis, A. macrosporus, and A. silvaticus. A particularly rich source of selenium could be obtained from selenium-enriched mushrooms that are cultivated on a substrate fortified with selenium (as inorganic salt or selenized-yeast). The Se-enriched Champignon Mushroom could contain up to 30 or 110 microg Se/g dw, while the Varnished Polypore (Ganoderma lucidum) could contain up to 72 microg Se/g dw. An increasingly growing database on chemical forms of selenium of mushrooms indicates that the seleno-compounds identified in carpophore include selenocysteine, selenomethionine, Se-methylselenocysteine, selenite, and several unidentified seleno-compounds; their proportions vary widely. Some aspects of environmental selenium occurrence and human body pharmacokinetics and nutritional needs will also be briefly discussed in this review.

Selenium in the Blackfoot, Salt, and Bear River Watersheds

Science.gov (United States)

Hamilton, S.J.; Buhl, K.J.

2005-01-01

Nine stream sites in the Blackfoot River, Salt River, and Bear River watersheds in southeast Idaho, USA were sampled in May 2001 for water, surficial sediment, aquatic plants, aquatic invertebrates, and fish. Selenium was measured in these aquatic ecosystem components, and a hazard assessment was performed on the data. Water quality characteristics such as pH, hardness, and specific conductance were relatively uniform among the nine sites. Of the aquatic components assessed, water was the least contaminated with selenium because measured concentrations were below the national water quality criterion of 5 μ g/L at eight of the nine sites. In contrast, selenium was elevated in sediment, aquatic plants, aquatic invertebrates, and fish from several sites, suggesting deposition in sediments and food web cycling through plants and invertebrates. Selenium was elevated to concentrations of concern in fish at eight sites (> 4 μ g/g in whole body). A hazard assessment of selenium in the aquatic environment suggested a moderate hazard at upper Angus Creek (UAC) and Smoky Creek (SC), and high hazard at Little Blackfoot River (LiB), Blackfoot River gaging station (BGS), State Land Creek (SLC), upper (UGC) and lower Georgetown Creek (LGC), Deer Creek (DC), and Crow Creek (CC). The results of this study indicate that selenium concentrations from the phosphate mining area of southeast Idaho were sufficiently elevated in several ecosystem components to cause adverse effects to aquatic resources in southeastern Idaho.

Binary mixtures of mercury/ selenium, and lead/selenium

African Journals Online (AJOL)

Physiologically-based biokinetic models have been developed for predicting simultaneously the Absorption, Distribution, Metabolism and Elimination (ADME) properties of lead (Pb) and selenium (Se), and mercury (Hg) and selenium in a number of target tissues of humans. This was done for three population groups, ...

Chemical Form of Selenium in Naturally Selenium-Rich Lentils (Lens Culinaris L.) From Saskatchewan

Energy Technology Data Exchange (ETDEWEB)

Thavarajah, D.; Vandenberg, A.; George, G.N.; Pickering, I.J.

2009-06-04

Lentils (Lens culinaris L.) are a source of many essential dietary components and trace elements for human health. In this study we show that lentils grown in the Canadian prairies are additionally enriched in selenium, an essential micronutrient needed for general well-being, including a healthy immune system and protection against cancer. Selenium K near-edge X-ray absorption spectroscopy (XAS) has been used to examine the selenium biochemistry of two lentil cultivars grown in various locations in Saskatchewan, Canada. We observe significant variations in total selenium concentration with geographic location and cultivar; however, almost all the selenium (86--95%) in these field-grown lentils is present as organic selenium modeled as selenomethionine with a small component (5--14%) as selenate. As the toxicities of certain forms of arsenic and selenium are antagonistic, selenium-rich lentils may have a pivotal role to play in alleviating the chronic arsenic poisoning in Bangladesh.

Association Between Selenium and Malondialdehyde as an Efficient Biomarker of Oxidative Stress in Infantile Cardiac Surgery.

Science.gov (United States)

de Oliveira Ulbrecht, Marlice Oliveira; Gonçalves, Daniel Araujo; Zanoni, Lourdes Zélia Garcia; do Nascimento, Valter Aragão

2018-05-12

The present work describes a method to quantify the level of oxidative stress in infantile cardiac surgery. Fifteen patients, 6 girls and 9 boys, aged between 3 months and 16 years were divided into three groups. The first group sought to quantify the oxidative stress from differing concentrations of selenium. The second group used malondialdehyde as an indicator of oxidative stress. Finally, the third group quantified oxidative stress by normalizing the selenium concentration via malondialdehyde. Blood aliquots of 1.50 ml, drawn from the radial artery, were collected and centrifuged for quantification of Se and MDA in plasma. The statistical method ANOVA was used with a 95% confidence interval to indicate significant statistical differences between the post- and pre-operative stage for each group. The concentrations of malondialdehyde were measured by using UV-Vis following the thiobarbituric acid reaction method. For quantification of selenium, the samples were submitted to assisted microwave digestion and measured by ICP OES. In the first two groups, it was not possible to affirm that selenium and malondialdehyde could be biomarkers of oxidative stress, so a statistic test (ANOVA) was performed. However, the selenium/malondialdehyde ratios in the pre-operative and post-operative stage were 2.10 ± 0.70 and 3.20 ± 0.40, respectively. The ANOVA test confirmed a statistically significant difference between the pre- and post-operative stages with p value = 0.004. Here, the ratio of selenium concentration by malondialdehyde was confirmed to be an effective parameter for demonstration and quantification of oxidative stress activity at the post-operative stage.

Efficient Resource Management in Cloud Computing

OpenAIRE

Rushikesh Shingade; Amit Patil; Shivam Suryawanshi; M. Venkatesan

2015-01-01

Cloud computing, one of the widely used technology to provide cloud services for users who are charged for receiving services. In the aspect of a maximum number of resources, evaluating the performance of Cloud resource management policies are difficult to optimize efficiently. There are different simulation toolkits available for simulation and modelling the Cloud computing environment like GridSim CloudAnalyst, CloudSim, GreenCloud, CloudAuction etc. In proposed Efficient Resource Manage...

Resources for our Future. Key issues and best practices in resource efficiency

Energy Technology Data Exchange (ETDEWEB)

Weterings, R.; Bastein, T.; Tukker, A. [TNO, Delft (Netherlands); Rademaker, M.; De Ridder, M. [The Hague Centre for Strategic studies HCSS, Den Haag (Netherlands)

2013-08-15

This book provides an analysis of the issues surrounding international resources and inspiring accounts of industrial best practices. The book consists of two distinct parts. The first part of the book brings together the results of years of research into the geopolitical, economic and ecological dimensions of material scarcity and resource efficiency. Chapter 2 discusses the main challenges and constraints related to the use of energy resources, water and land, industrial and metallic minerals, construction minerals and biotic resources, including water use and ecosystem degradation. The chapter also addresses important linkages between these various resources. Chapter 3 describes the international trends that are shaping the geopolitics of natural resources and looks at the implications for Europe and the Netherlands. Chapter 4 presents a wide range of strategies by which governments, producers and consumers may contribute to the more sustainable use of natural resources. The second part of the book describes 21 inspiring best practices in resource efficiency in a variety of industrial sectors. Based on a series of interviews with industrial pioneers, these chapters relate their first-hand experiences in improving resource efficiency. These business cases demonstrate that innovation and entrepreneurship can result in substantial improvements in resource efficiency. Chapter 5 focuses on best practices in the built environment, where substantial amounts of energy and minerals are used. Chapter 6 presents four ambitious strategies to promote sustainable food production and consumption. Chapter 7 describes recent developments in the chemical process industry, which produces most of the ingredients, compounds and semi-products for the vast range of products used by society. Chapter 8 provides four examples of the state-of-the-art in resource efficiency in the metal and high-tech industries. This chapter presents four business cases highlighting the benefits of the

Selenium essentials

CERN Document Server

Sams, Prashanth

2015-01-01

If you are a developer who wants to migrate from Selenium RC or any other automation tool to Selenium WebDriver, then this book is for you. Knowledge of automation tools is necessary to follow the examples in this book.

Selenium for preventing cancer

Directory of Open Access Journals (Sweden)

Gabriele Dennert

Full Text Available BACKGROUND: Selenium is a trace element essential to humans. Higher selenium exposure and selenium supplements have been suggested to protect against several types of cancers. OBJECTIVE: Two research questions were addressed in this review: What is the evidence for: 1. an aetiological relationship between selenium exposure and cancer risk in women and men?; 2. the efficacy of selenium supplementation for cancer prevention in women and men? SEARCH STRATEGY: We searched electronic databases and bibliographies of reviews and included publications. SELECTION CRITERIA: We included prospective observational studies to answer research question (a and randomised controlled trials (RCTs to answer research question (b. DATA COLLECTION AND ANALYSIS: We conducted random effects meta-analyses of epidemiological data when five or more studies were retrieved for a specific outcome. We made a narrative summary of data from RCTs. MAIN RESULTS: We included 49 prospective observational studies and six RCTs. In epidemiologic data, we found a reduced cancer incidence (summary odds ratio, OR, 0.69; 95% confidence interval, CI, 0.53 to 0.91 and mortality (OR 0.55, 95% CI 0.36 to 0.83 with higher selenium exposure. Cancer risk was more pronouncedly reduced in men (incidence: OR 0.66, 95% CI 0.42 to 1.05 than in women (incidence: OR 0.90, 95% CI 0.45 to 1.77. These findings have potential limitations due to study design, quality and heterogeneity of the data, which complicated the interpretation of the summary statistics. The RCTs found no protective efficacy of selenium yeast supplementation against non-melanoma skin cancer or L-selenomethionine supplementation against prostate cancer. Study results for the prevention of liver cancer with selenium supplements were inconsistent and studies had an unclear risk of bias. The results of the Nutritional Prevention of Cancer Trial (NPCT and SELECT raised concerns about possible harmful effects of selenium supplements. AUTHORS

Matrix modification with silver for the electrothermal atomization of arsenic and selenium

Science.gov (United States)

Sanzolone, R.F.; Chao, T.T.

1981-01-01

Silver as a matrix modifier is shown to improve the carbon-rod atomization of both arsenic and selenium for atomic absorption spectrometry. Compared to nickel, the efficiency of silver is greater for arsenic and about the same for selenium. Silver fulfils two functions in its reaction, namely stabilization during the ashing stage and enhancement of absorbance in the final atomization. ?? 1981.

Common challenge in resource efficiency improvement

International Nuclear Information System (INIS)

La Motta, Sergio; Peronaci, Marcello

2015-01-01

Energy efficiency and technology improvements on their own will not achieve the Low Carbon Societies (LCS) goals. Thus, resource efficiency and a circular economy are keys to a low carbon society. Resource efficiency improvement potential has been analysed from the industrial and territorial management perspectives. Exploring synergies between LCS and the larger area of sustainable development and green economy, highlighting co-benefits and trade-offs, is of utmost importance to pave the way to a more equitable and largely participated low carbon transition.

Review on Nano SeleniumProduced by Bacteria

Directory of Open Access Journals (Sweden)

LI Ji-xiang

2014-12-01

Full Text Available Selenium (Se is a kind of essential trace element for people and animal, while ionic state of selenium is toxic with high concentrations and will cause the selenium pollution. Nano-selenium is stable, nontoxic with higher biological activity. Application of bacteria reducing selenite or selenate to biological nano-selenium has great potential in selenium pollution control and nano-selenium production. This review summarizes the research progress of the red elemental nano-selenium reduced by bacteria including characteristics and application of nano-selenium, effects of carbon and nitrogen source, oxygen, temperature and pH in bacteria nano-selenium production, and molecular mechanisms of nano-selenium reduced by bacteria.

Why Nature Chose Selenium.

Science.gov (United States)

Reich, Hans J; Hondal, Robert J

2016-04-15

The authors were asked by the Editors of ACS Chemical Biology to write an article titled "Why Nature Chose Selenium" for the occasion of the upcoming bicentennial of the discovery of selenium by the Swedish chemist Jöns Jacob Berzelius in 1817 and styled after the famous work of Frank Westheimer on the biological chemistry of phosphate [Westheimer, F. H. (1987) Why Nature Chose Phosphates, Science 235, 1173-1178]. This work gives a history of the important discoveries of the biological processes that selenium participates in, and a point-by-point comparison of the chemistry of selenium with the atom it replaces in biology, sulfur. This analysis shows that redox chemistry is the largest chemical difference between the two chalcogens. This difference is very large for both one-electron and two-electron redox reactions. Much of this difference is due to the inability of selenium to form π bonds of all types. The outer valence electrons of selenium are also more loosely held than those of sulfur. As a result, selenium is a better nucleophile and will react with reactive oxygen species faster than sulfur, but the resulting lack of π-bond character in the Se-O bond means that the Se-oxide can be much more readily reduced in comparison to S-oxides. The combination of these properties means that replacement of sulfur with selenium in nature results in a selenium-containing biomolecule that resists permanent oxidation. Multiple examples of this gain of function behavior from the literature are discussed.

AN ANALYTICAL METHOD FOR CHEMICAL SPECIATION OF SELENIUM IN SOIL

Directory of Open Access Journals (Sweden)

Constantin Luca

2010-10-01

Full Text Available Selenium is an essential microelement, sometimes redoubtable, through its beneficial role - risk depending on its concentration in the food chain, at low dose is an important nutrient in the life of humans and animals, contrary at high doses, it becomes toxic. Selenium may be find itself in the environment (soil, sediment, water in many forms (oxidized, reduced, organometallic which determine their mobility and toxicity. Determination of chemical speciation (identification of different chemical forms provides much more complete information for a better understanding of the behavior and the potential impact on the environment. In this work we present the results of methodological research on the extraction of sequential forms of selenium in the soil and the coupling of analytical methods capable of identifying very small amounts of selenium in soils An efficient scheme of sequential extractions forms of selenium (SES consisting in atomic absorption spectrometry coupled with hydride generation (HGAAS has been developed into five experimental steps, detailed in the paper. This operational scheme has been applied to the analysis of chemical speciation in the following areas: the Bărăgan Plain and Central Dobrogea of Romania.

New challenge in the speciation of selenium. Measurement and production on nano selenium

Energy Technology Data Exchange (ETDEWEB)

Prokisch, J; Sztrik, A; Babka, B; Zommara, M; Daroczi, L [Debrecen University, Centre for Agricultural Sciences and Engineering, Debrecen (Hungary). Institute of Bio- and Environmental Energetics

2009-07-01

Complete text of publication follows. We have found that several species of probiotic bacteria also used in food industry for making yogurts is capable of producing spherical elemental selenium nanospheres having an average diameter in the range of 50-500 nm when 1-1000 mg/L selenium was added to the medium in the form of selenite ions. Elemental selenium produced thereby has a high degree of purity, is spherical, and its size and crystalline form depends on the bacterium species applied. We have found that some species of the probiotic yogurt bacteria (e.g. Bifidobacterium bifidum or Bifidobacterium longum) are capable of producing the grey crystalline form of elemental selenium which is so far unprecedented in the art for any bacteria capable of producing elemental selenium nanoparticles. Our finding, therefore, enables the first time the development of economical industrial bacterial fermentation based processes for the production of a high quality elemental selenium material comprising uniformly sized grey or red nanospheres having an average diameter in the range of 50-500 nm. The size and the crystalline form of the produced nanosized (50-500 nm) spherical particles is defined by the selected microorganism. This genetic pre-determination result in reproducible production of a material having individual characteristics which can be used in numerous fields of industry and research. The produced nano selenium could be a good raw material for a production of certified reference materials. The measurement of the produced elemental nanoselenium is a new challenge for the speciation analysis. A sample preparation and measurement method was developed and investigated for the analysis of different selenium forms by HPLC-AFS system. The atomic fluorescence (AFS) was a reliable and simple detection method for the elemental nano selenium. The elemental selenium can produce hydride in the system or can be converted to selenite with HCl/H{sub 2}O{sub 2} digestion.

Selenium Enrichment of Horticultural Crops.

Science.gov (United States)

Puccinelli, Martina; Malorgio, Fernando; Pezzarossa, Beatrice

2017-06-04

The ability of some crops to accumulate selenium (Se) is crucial for human nutrition and health. Selenium has been identified as a cofactor of the enzyme glutathione peroxidase, which is a catalyzer in the reduction of peroxides that can damage cells and tissues, and can act as an antioxidant. Plants are the first link in the food chain, which ends with humans. Increasing the Se quantity in plant products, including leafy and fruity vegetables, and fruit crops, without exceeding the toxic threshold, is thus a good way to increase animal and human Se intake, with positive effects on long-term health. In many Se-enriched plants, most Se is in its major organic form. Given that this form is more available to humans and more efficient in increasing the selenium content than inorganic forms, the consumption of Se-enriched plants appears to be beneficial. An antioxidant effect of Se has been detected in Se-enriched vegetables and fruit crops due to an improved antioxidative status and to a reduced biosynthesis of ethylene, which is the hormone with a primary role in plant senescence and fruit ripening. This thus highlights the possible positive effect of Se in preserving a longer shelf-life and longer-lasting quality.

Selenium Enrichment of Horticultural Crops

Directory of Open Access Journals (Sweden)

Martina Puccinelli

2017-06-01

Full Text Available The ability of some crops to accumulate selenium (Se is crucial for human nutrition and health. Selenium has been identified as a cofactor of the enzyme glutathione peroxidase, which is a catalyzer in the reduction of peroxides that can damage cells and tissues, and can act as an antioxidant. Plants are the first link in the food chain, which ends with humans. Increasing the Se quantity in plant products, including leafy and fruity vegetables, and fruit crops, without exceeding the toxic threshold, is thus a good way to increase animal and human Se intake, with positive effects on long-term health. In many Se-enriched plants, most Se is in its major organic form. Given that this form is more available to humans and more efficient in increasing the selenium content than inorganic forms, the consumption of Se-enriched plants appears to be beneficial. An antioxidant effect of Se has been detected in Se-enriched vegetables and fruit crops due to an improved antioxidative status and to a reduced biosynthesis of ethylene, which is the hormone with a primary role in plant senescence and fruit ripening. This thus highlights the possible positive effect of Se in preserving a longer shelf-life and longer-lasting quality.

Selenopeptides and elemental selenium in Thunbergia alata after exposure to selenite: quantification method for elemental selenium.

Science.gov (United States)

Aborode, Fatai Adigun; Raab, Andrea; Foster, Simon; Lombi, Enzo; Maher, William; Krupp, Eva M; Feldmann, Joerg

2015-07-01

Three month old Thunbergia alata were exposed for 13 days to 10 μM selenite to determine the biotransformation of selenite in their roots. Selenium in formic acid extracts (80 ± 3%) was present as selenopeptides with Se-S bonds and selenium-PC complexes (selenocysteinyl-2-3-dihydroxypropionyl-glutathione, seleno-phytochelatin2, seleno-di-glutathione). An analytical method using HPLC-ICPMS to detect and quantify elemental selenium in roots of T. alata plants using sodium sulfite to quantitatively transform elemental selenium to selenosulfate was also developed. Elemental selenium was determined as 18 ± 4% of the total selenium in the roots which was equivalent to the selenium not extracted using formic acid extraction. The results are in an agreement with the XAS measurements of the exposed roots which showed no occurrence of selenite or selenate but a mixture of selenocysteine and elemental selenium.

Recovery of palladium, cesium, and selenium from heavy metal alkali borosilicate glass by combination of heat treatment and leaching processes

Energy Technology Data Exchange (ETDEWEB)

Xu, Zhanglian; Okada, Takashi, E-mail: t-okada@u-fukui.ac.jp; Nishimura, Fumihiro; Yonezawa, Susumu

2017-06-05

Highlights: • A separation technique of both noble and less noble metal from glass is studied. • Via reductive heat treatment, 80% of palladium is extracted in liquid bismuth. • Sodium–potassium-rich materials with cesium and selenium are phase separated. • From the materials, over 80% of cesium and selenium are extracted in water. - Abstract: Reductive heat-treatment and leaching process were applied to a simulated lead or bismuth soda-potash-borosilicate glass with palladium, cesium, and selenium to separate these elements. In the reductive heat treatment, palladium is extracted in liquid heavy metal phase generated by the reduction of the heavy metal oxides, whereas cesium and selenium are concentrated in phase separated Na–K-rich materials on the glass surface. From the materials, cesium and selenium can be extracted in water, and the selenium extraction was higher in the treatment of the bismuth containing glass. The chemical forms of palladium in the glass affected the extraction efficiencies of cesium and selenium. Among the examined conditions, in the bismuth glass treatment, the cesium and selenium extraction efficiencies in water were over 80%, and that of palladium in liquid bismuth was over 80%.

Blood selenium levels and contribution of food groups to selenium intake in adolescent girls in Iceland.

Science.gov (United States)

Gudmundsdottir, Edda Y; Gunnarsdottir, Ingibjorg; Thorlacius, Arngrimur; Reykdal, Olafur; Gunnlaugsdottir, Helga; Thorsdottir, Inga; Steingrimsdottir, Laufey

2012-01-01

Significant changes have been reported in dietary habits and food availability in Iceland that would be expected to compromise selenium intake and status, especially among young people. These include substantial decreases in the consumption of fish and milk, as well as the selenium content of imported wheat. The aim of this study was to assess selenium in the diet and whole blood of adolescent girls, as well as define the most important foods contributing to intake and blood concentrations of selenium. The subjects were 96 randomly selected girls, aged 16-20, who answered a validated food frequency questionnaire (FFQ) for dietary assessment. Selenium intake from each food group was calculated in µg/day. Blood samples were collected for measurement of whole blood selenium. Mean dietary selenium was 51±25 µg/day. Milk/dairy products, including cheese, contributed 36±14% of total dietary selenium; fish 18±12%; and bread/cereal products 13±6%. Mean whole blood selenium was 117±12 µg/l (range 90-208); nearly 90% of subjects were above the optimal level of 100 µg/l. Fish and bread/cereal products were the only foods significantly correlated with selenium in blood (r=0.32; P=0.002 and r=0.22; P=0.04, respectively) while no correlation was found with milk and dairy products in spite of their greater contribution to total selenium intake. In this population of Icelandic adolescent girls, selenium intake and status seem acceptable. Judging from associations between intake and blood levels, fish and cereals may be the most important contributors to blood selenium.

Blood selenium levels and contribution of food groups to selenium intake in adolescent girls in Iceland

Directory of Open Access Journals (Sweden)

Ingibjorg Gunnarsdottir

2012-08-01

Full Text Available Background/objectives: Significant changes have been reported in dietary habits and food availability in Iceland that would be expected to compromise selenium intake and status, especially among young people. These include substantial decreases in the consumption of fish and milk, as well as the selenium content of imported wheat. The aim of this study was to assess selenium in the diet and whole blood of adolescent girls, as well as define the most important foods contributing to intake and blood concentrations of selenium. Design: The subjects were 96 randomly selected girls, aged 16–20, who answered a validated food frequency questionnaire (FFQ for dietary assessment. Selenium intake from each food group was calculated in µg/day. Blood samples were collected for measurement of whole blood selenium. Results: Mean dietary selenium was 51±25 µg/day. Milk/dairy products, including cheese, contributed 36±14% of total dietary selenium; fish 18±12%; and bread/cereal products 13±6%. Mean whole blood selenium was 117±12 µg/l (range 90–208; nearly 90% of subjects were above the optimal level of 100 µg/l. Fish and bread/cereal products were the only foods significantly correlated with selenium in blood (r=0.32; P = 0.002 and r=0.22; P = 0.04, respectively while no correlation was found with milk and dairy products in spite of their greater contribution to total selenium intake. Conclusion: In this population of Icelandic adolescent girls, selenium intake and status seem acceptable. Judging from associations between intake and blood levels, fish and cereals may be the most important contributors to blood selenium.

Microbial selenium sulfide reduction for selenium recovery from wastewater

NARCIS (Netherlands)

Hageman, S.P.W.; Weijden, van der R.D.; Stams, A.J.M.; Cappellen, van P.; Buisman, C.J.N.

2017-01-01

Microbial reduction of selenium sulfide (SeS2) is a key step in a new treatment process to recover selenium from selenate and selenite streams. In this process, selenate is first reduced to selenite, and subsequently selenite is reduced by sulfide and precipitates from the solution as SeS2. The

High-resolution imaging of selenium in kidneys: a localized selenium pool associated with glutathione peroxidase 3

Energy Technology Data Exchange (ETDEWEB)

Malinouski, M.; Kehr, S.; Finney, L.; Vogt, S.; Carlson, B.A.; Seravalli, J.; Jin, R.; Handy, D.E.; Park, T.J.; Loscalzo, J.; Hatfield, D.L.; Gladyshev, V.N. (Harvard-Med)

2012-04-17

Recent advances in quantitative methods and sensitive imaging techniques of trace elements provide opportunities to uncover and explain their biological roles. In particular, the distribution of selenium in tissues and cells under both physiological and pathological conditions remains unknown. In this work, we applied high-resolution synchrotron X-ray fluorescence microscopy (XFM) to map selenium distribution in mouse liver and kidney. Liver showed a uniform selenium distribution that was dependent on selenocysteine tRNA{sup [Ser]Sec} and dietary selenium. In contrast, kidney selenium had both uniformly distributed and highly localized components, the latter visualized as thin circular structures surrounding proximal tubules. Other parts of the kidney, such as glomeruli and distal tubules, only manifested the uniformly distributed selenium pattern that co-localized with sulfur. We found that proximal tubule selenium localized to the basement membrane. It was preserved in Selenoprotein P knockout mice, but was completely eliminated in glutathione peroxidase 3 (GPx3) knockout mice, indicating that this selenium represented GPx3. We further imaged kidneys of another model organism, the naked mole rat, which showed a diminished uniformly distributed selenium pool, but preserved the circular proximal tubule signal. We applied XFM to image selenium in mammalian tissues and identified a highly localized pool of this trace element at the basement membrane of kidneys that was associated with GPx3. XFM allowed us to define and explain the tissue topography of selenium in mammalian kidneys at submicron resolution.

Energy Efficiency Resources to Support State Energy Planning

Energy Technology Data Exchange (ETDEWEB)

Office of Strategic Programs, Strategic Priorities and Impact Analysis Team

2017-06-01

An early step for most energy efficiency planning is to identify and quantify energy savings opportunities, and then to understand how to access this potential. The U.S. Department of Energy’s Office of Energy Efficiency and Renewable Energy offers resources that can help with both of these steps. This fact sheet presents those resources. The resources are also available on the DOE State and Local Solution Center on the "Energy Efficiency: Savings Opportunities and Benefits" page: https://energy.gov/eere/slsc/energy-efficiency-savings-opportunities-and-benefits.

High-Resolution Imaging of Selenium in Kidneys: A Localized Selenium Pool Associated with Glutathione Peroxidase 3

Science.gov (United States)

Malinouski, Mikalai; Kehr, Sebastian; Finney, Lydia; Vogt, Stefan; Carlson, Bradley A.; Seravalli, Javier; Jin, Richard; Handy, Diane E.; Park, Thomas J.; Loscalzo, Joseph; Hatfield, Dolph L.

2012-01-01

Abstract Aim: Recent advances in quantitative methods and sensitive imaging techniques of trace elements provide opportunities to uncover and explain their biological roles. In particular, the distribution of selenium in tissues and cells under both physiological and pathological conditions remains unknown. In this work, we applied high-resolution synchrotron X-ray fluorescence microscopy (XFM) to map selenium distribution in mouse liver and kidney. Results: Liver showed a uniform selenium distribution that was dependent on selenocysteine tRNA[Ser]Sec and dietary selenium. In contrast, kidney selenium had both uniformly distributed and highly localized components, the latter visualized as thin circular structures surrounding proximal tubules. Other parts of the kidney, such as glomeruli and distal tubules, only manifested the uniformly distributed selenium pattern that co-localized with sulfur. We found that proximal tubule selenium localized to the basement membrane. It was preserved in Selenoprotein P knockout mice, but was completely eliminated in glutathione peroxidase 3 (GPx3) knockout mice, indicating that this selenium represented GPx3. We further imaged kidneys of another model organism, the naked mole rat, which showed a diminished uniformly distributed selenium pool, but preserved the circular proximal tubule signal. Innovation: We applied XFM to image selenium in mammalian tissues and identified a highly localized pool of this trace element at the basement membrane of kidneys that was associated with GPx3. Conclusion: XFM allowed us to define and explain the tissue topography of selenium in mammalian kidneys at submicron resolution. Antioxid. Redox Signal. 16, 185–192. PMID:21854231

Biological selenium removal from wastewaters

NARCIS (Netherlands)

Lenz, M.

2008-01-01

In this thesis, microbial conversion of water-soluble, highly toxic forms of selenium (selenate, selenite) to less bioavailable elemental selenium was investigated. By the exploitation of different groups of microorganisms (selenium-respiring, nitrate-reducing and sulfate-reducing bacteria,

Impact of Selenium Addition to Animal Feeds on Human Selenium Status in Serbia

Directory of Open Access Journals (Sweden)

Zoran Pavlovic

2018-02-01

Full Text Available Research conducted during the 1980s demonstrated Se deficiency in humans. Increased inclusion of selenium in animal feeds started from the year 2000 onwards. The aim of this study was to estimate the effects of selenium inclusion in animal feeds on human selenium status and dietary habits of the Serbian population related to food of animal origin. Plasma selenium concentration in healthy adult volunteers, including residents of one of the regions with the lowest (Eastern Serbia, n = 60 and of one of the regions with the highest Se serum levels reported in the past (Belgrade, n = 82, was determined by hydride generation atomic absorption spectrometry. Multivariate analysis was employed to determine the correlation between Se plasma levels and dietary intake data derived from food frequency questionnaires and laboratory tests. The mean plasma Se level of the participants was 84.3 ± 15.9 μg/L (range: 47.3–132.1 μg/L, while 46% of participants had plasma Se levels lower than 80 μg/L. Frequency of meat, egg, and fish consumption was significantly correlated with plasma selenium level (r = 0.437, p = 0.000. Selenium addition to animal feed in the quantity of 0.14 mg/kg contributed to the improvement of human plasma selenium levels by approximately 30 μg/L.

Selenium in diet

Science.gov (United States)

... how much of the mineral was in the soil where the plants grew. Brazil nuts are a very good source of selenium. Fish, shellfish , red meat, grains, eggs, chicken, liver, and garlic ... soil have higher levels of selenium. Brewer's yeast, wheat ...

Removal of Selenium and Nitrate in Groundwater Using Organic Carbon-Based Reactive Mixtures

Science.gov (United States)

An, Hyeonsil; Jeen, Sung-Wook

2016-04-01

Treatment of selenium and nitrate in groundwater was evaluated through column experiments. Four columns consisting of reactive mixtures, either organic carbon-limestone (OC-LS) or organic carbon-zero valent iron (OC-ZVI), were used to determine the removal efficiency of selenium with different concentrations of nitrate. The source waters were collected from a mine site in Korea or were prepared artificially based on the mine drainage water or deionized water, followed by spiking of elevated concentrations of Se (40 mg/L) and nitrate (100 or 10 mg/L as NO3-N). The results for the aqueous chemistry showed that selenium and nitrate were effectively removed both in the mine drainage water and deionized water-based artificial input solution. However, the removal of selenium was delayed when selenium and nitrate coexisted in the OC-LS columns. The removal of selenium was not significant when the influent nitrate concentration was 100 mg/L as NO3-N, while most of nitrate was gradually removed within the columns. In contrast, 94% of selenium was removed when the influent nitrate concentration was reduced to 10 mg/L as NO3-N. In the OC-ZVI column, selenium and nitrate was removed almost simultaneously and completely even with the high nitrate concentration; however, a high concentration of ammonia was produced as a by-product of abiotic reaction between ZVI and nitrate. The elemental analysis for the solid samples after the termination of the experiments showed that selenium was accumulated in the reactive materials where removal of aqueous-phase selenium mostly occurred. The X-ray absorption near-edge structure (XANES) study indicated that selenium existed in the forms of SeS2 and Se(0) in the OC-LS column, while selenium was present in the forms of FeSe, SeS2 and absorbed Se(IV) in the OC-ZVI column. This study shows that OC-based reactive mixtures have an ability to remove selenium and nitrate in groundwater. However, the removal of selenium was influenced by the high

Long-term selenium status in humans

International Nuclear Information System (INIS)

Baskett, C.K.; Spate, V.L.; Mason, M.M.; Nichols, T.A.; Williams, A.; Dubman, I.M.; Gudino, A.; Denison, J.; Morris, J.S.

2001-01-01

The association of sub-optimal selenium status with increased risk factors for some cancers has been reported in two recent epidemiological studies. In both studies the same threshold in selenium status was observed, below which, cancer incidence increased. To assess the use of nails as a biologic monitor to measure the long-term selenium status, an eight-year longitudinal study was undertaken with a group of 11 adult subjects, 5 women and 6 men. Selenium has been measured by instrumental neutron activation analysis. Differences between fingernails and toenails with be discussed. In addition, the results will be discussed in the context of the long-term stability of the nail monitor to measure selenium status during those periods when selenium determinants are static; and the changes that occur as a result of selenium supplementation. (author)

Mechanism of Selenium Loss in Copper Slag

Science.gov (United States)

Desai, Bhavin; Tathavadkar, Vilas; Basu, Somnath

2018-03-01

During smelting of copper sulfide concentrate, selenium is distributed between silica-saturated iron-silicate slag and copper-iron sulfide matte. The recovery coefficients of selenium between slag and matte were determined as a function of the initial concentration of selenium at 1523 K (1250 °C) under an inert atmosphere in a vertical tubular furnace. The initial concentration of selenium was varied by the addition of metallic selenium as well as selenium dioxide to the mixture of slag and matte. Analysis of the results indicated high affinity of selenium for matte. The apparent loss of selenium with the slag was attributed to the presence of selenium-enriched matte particles entrapped in the slag, rather than dissolved SeO2. The mechanisms proposed by previous investigators were discussed and also compared with the results of the present investigation.

Mechanism of Selenium Loss in Copper Slag

Science.gov (United States)

Desai, Bhavin; Tathavadkar, Vilas; Basu, Somnath

2018-06-01

During smelting of copper sulfide concentrate, selenium is distributed between silica-saturated iron-silicate slag and copper-iron sulfide matte. The recovery coefficients of selenium between slag and matte were determined as a function of the initial concentration of selenium at 1523 K (1250 °C) under an inert atmosphere in a vertical tubular furnace. The initial concentration of selenium was varied by the addition of metallic selenium as well as selenium dioxide to the mixture of slag and matte. Analysis of the results indicated high affinity of selenium for matte. The apparent loss of selenium with the slag was attributed to the presence of selenium-enriched matte particles entrapped in the slag, rather than dissolved SeO2. The mechanisms proposed by previous investigators were discussed and also compared with the results of the present investigation.

Selenium and Prostate Cancer Prevention: Insights from the Selenium and Vitamin E Cancer Prevention Trial (SELECT)

Science.gov (United States)

Nicastro, Holly L.; Dunn, Barbara K.

2013-01-01

The Selenium and Vitamin E Cancer Prevention Trial (SELECT) was conducted to assess the efficacy of selenium and vitamin E alone, and in combination, on the incidence of prostate cancer. This randomized, double-blind, placebo-controlled, 2 × 2 factorial design clinical trial found that neither selenium nor vitamin E reduced the incidence of prostate cancer after seven years and that vitamin E was associated with a 17% increased risk of prostate cancer compared to placebo. The null result was surprising given the strong preclinical and clinical evidence suggesting chemopreventive activity of selenium. Potential explanations for the null findings include the agent formulation and dose, the characteristics of the cohort, and the study design. It is likely that only specific subpopulations may benefit from selenium supplementation; therefore, future studies should consider the baseline selenium status of the participants, age of the cohort, and genotype of specific selenoproteins, among other characteristics, in order to determine the activity of selenium in cancer prevention. PMID:23552052

Selenium and Prostate Cancer Prevention: Insights from the Selenium and Vitamin E Cancer Prevention Trial (SELECT

Directory of Open Access Journals (Sweden)

Holly L. Nicastro

2013-04-01

Full Text Available The Selenium and Vitamin E Cancer Prevention Trial (SELECT was conducted to assess the efficacy of selenium and vitamin E alone, and in combination, on the incidence of prostate cancer. This randomized, double-blind, placebo-controlled, 2 × 2 factorial design clinical trial found that neither selenium nor vitamin E reduced the incidence of prostate cancer after seven years and that vitamin E was associated with a 17% increased risk of prostate cancer compared to placebo. The null result was surprising given the strong preclinical and clinical evidence suggesting chemopreventive activity of selenium. Potential explanations for the null findings include the agent formulation and dose, the characteristics of the cohort, and the study design. It is likely that only specific subpopulations may benefit from selenium supplementation; therefore, future studies should consider the baseline selenium status of the participants, age of the cohort, and genotype of specific selenoproteins, among other characteristics, in order to determine the activity of selenium in cancer prevention.

Selenium for preventing cancer.

Science.gov (United States)

Vinceti, Marco; Filippini, Tommaso; Del Giovane, Cinzia; Dennert, Gabriele; Zwahlen, Marcel; Brinkman, Maree; Zeegers, Maurice Pa; Horneber, Markus; D'Amico, Roberto; Crespi, Catherine M

2018-01-29

This review is the third update of the Cochrane review "Selenium for preventing cancer". Selenium is a naturally occurring element with both nutritional and toxicological properties. Higher selenium exposure and selenium supplements have been suggested to protect against several types of cancer. To gather and present evidence needed to address two research questions:1. What is the aetiological relationship between selenium exposure and cancer risk in humans?2. Describe the efficacy of selenium supplementation for cancer prevention in humans. We updated electronic searches of the Cochrane Central Register of Controlled Trials (CENTRAL; 2017, Issue 2), MEDLINE (Ovid, 2013 to January 2017, week 4), and Embase (2013 to 2017, week 6), as well as searches of clinical trial registries. We included randomised controlled trials (RCTs) and longitudinal observational studies that enrolled adult participants. We performed random-effects (RE) meta-analyses when two or more RCTs were available for a specific outcome. We conducted RE meta-analyses when five or more observational studies were available for a specific outcome. We assessed risk of bias in RCTs and in observational studies using Cochrane's risk assessment tool and the Newcastle-Ottawa Scale, respectively. We considered in the primary analysis data pooled from RCTs with low risk of bias. We assessed the certainty of evidence by using the GRADE approach. We included 83 studies in this updated review: two additional RCTs (10 in total) and a few additional trial reports for previously included studies. RCTs involved 27,232 participants allocated to either selenium supplements or placebo. For analyses of RCTs with low risk of bias, the summary risk ratio (RR) for any cancer incidence was 1.01 (95% confidence interval (CI) 0.93 to 1.10; 3 studies, 19,475 participants; high-certainty evidence). The RR for estimated cancer mortality was 1.02 (95% CI 0.80 to 1.30; 1 study, 17,444 participants). For the most frequently

Selenium in human mammary carcinogenesis

DEFF Research Database (Denmark)

Overvad, Kim; Grøn, P.; Langhoff, Otto

1991-01-01

/l and TNM stage II 76 +/- 13 micrograms selenium/l), indicating disease-mediated changes. The evaluation of selenium as a risk indicator in human breast cancer was therefore restricted to TNM stage I patients (n = 36). Multiple logistic regression analyses including variables associated with selenium levels...

Microbial volatilization of inorganic selenium from landfill leachate; Mikrobiologische Volatilisierung von anorganischem Selen aus Deponiesickerwaessern bei umweltrelevanten Konzentrationen

Energy Technology Data Exchange (ETDEWEB)

Peitzsch, Mirko; Kremer, Daniel; Kersten, Michael [Mainz Univ. (Germany). Inst. fuer Geowissenschaften

2010-04-15

Background, aim, and scope: Determination of the rates of microbial alkylation are of interest with respect to natural attenuation of harmful selenium concentrations or selenium charges in contaminated ecosystems. Materials and methods: Landfill gas and the headspace of microbial microcosm incubation vessels were sampled in Tedlar {sup registered} bags. On-line hyphenation of an efficient enrichment method (cryotrapping-cryofocusing), a gaschromatographic separation technique, and the sensitive ICP-MS detection system was used for speciation of volatile organoselenium compounds. A detection limit at the ultra trace level (pg Se) was achieved with this CT-CF-GC-ICP-MS technique. Results: Incubation of landfill leachate with Alternata alternata as an active methylating organism showed a production of volatile selenium compounds (DMSe, DMDSe, EMDSe, DEDSe) over the whole range of applied inorganic selenium concentrations (10 {mu}gL{sup -1} to 10 mgL{sup -1}), with volatilization rates of up to 10 mg m{sup -3}d{sup -1}. For selenium concentrations of 1 mgL{sup -1} in the nutrient broth, up to 7 % of the inorganic selenium was volatilized after one week. The same volatile selenium compounds were observed in landfill gas. Discussion: The amount of volatilized selenium was comparable to that found in other studies with microbial pure cultures as well as isolates from waters or soils, but at much lower initial concentrations used in the incubations. Conclusions: The alkylation of selenium in the enriched mixed culture from landfill leachate at environmentally relevant concentrations indicates that the organoselenium compounds of same species composition and distribution determined in landfill gas are produced by microorganisms. Recommendations and perspectives: The microbial alkylation of toxic inorganic selenium species to less toxic or non-toxic, volatile compounds is an efficient method for bioremediation of contaminated sites even at relatively low Se concentrations.

Selenium in food and health

National Research Council Canada - National Science Library

Reilly, Conor

2006-01-01

...) to be a carcinogen and banned as an additive in food. Selenium is considered by some to be a serious hazard to the environment and to animal health. Selenium-contaminated water has brought deformity and death to wildlife in nature reserves in western USA. There is even concern that because of selenium contamination of soil, crops supplied to the great cities of California could become unfit for human consumption. In large areas of China, endemic selenium toxicity is a hazard for locals who depend on cr...

Novel selenium-doped hydroxyapatite coatings for biomedical applications.

Science.gov (United States)

Rodríguez-Valencia, C; López-Álvarez, M; Cochón-Cores, B; Pereiro, I; Serra, J; González, P

2013-03-01

Nowadays there is a short-term need of investigating in orthopedic implants with a greater functionality, including an improved osseointegration and also antibacterial properties. The coating of metallic implants with hydroxyapatite (HA) remains to be the main proposal, but superior quality HA coatings with compositions closer to natural bone apatites, including carbonates, trace elements are required. Selenium is an essential nutrient in biological tissues and, at the same time, it also presents antibacterial properties. A pioneering study on the fabrication of selenium-doped carbonated hydroxyapatite (iHA:Se) coatings by Pulsed Laser Deposition (PLD) is presented. Different proportions of selenium were incorporated to obtain the iHA:Se coatings. Their physicochemical characterization, performed by SEM/EDS, FTIR, FT-Raman, Interferometric Profilometry and XPS, revealed typical columnar growth of HA in globular aggregates and the efficient incorporation of selenium into the HA coatings by the, most probably, substitution of SeO(3)(2-) groups in the CO(3)(2-) sites. Biological evaluation illustrated the absence of cytotoxicity when an amount of 0.6 at.% of Se was added to the iHA:Se coatings and excellent proliferation of the MC3T3-E1 preosteoblasts. Antibacterial properties were also proved with the inhibition of P. aeruginosa and S. aureus from establishing bacterial biofilms. Copyright © 2012 Wiley Periodicals, Inc.

Speciation of selenium dietary supplements; formation of S-(methylseleno)cysteine and other selenium compounds

International Nuclear Information System (INIS)

Amoako, Prince O.; Uden, Peter C.; Tyson, Julian F.

2009-01-01

Speciation of selenium is of interest because it is both essential and toxic to humans, depending on the species and the amount ingested. Following indications that selenium supplementation could reduce the incidence of some cancers, selenium-enriched yeast and other materials have been commercialized as supplements. Most dramatically however, the SELECT trial that utilized L-selenomethionine as the active supplement was terminated in 2008 and there is much debate regarding both the planning and the results of efficacy studies. Further, since dietary supplements are not regulated as pharmaceuticals, there are concerns about the quality, storage conditions, stability and selenium content in selenium supplements. Enzymatic hydrolysis enabled selenium speciation profiles to be obtained by high performance liquid chromatography with inductively coupled plasma mass spectrometry (HPLC-ICP-MS) and following derivatization gas chromatography with atomic emission detection (GC-AED). Coated fiber solid phase microextraction (SPME) was used to extract volatile selenium species for determination by GC-AED and GC-MS. Similar speciation patterns were observed between yeast-based supplements subject to extended storage and those heated briefly at elevated temperatures. All the yeast-based supplements and one yeast-free supplement formed S-(methylseleno)cysteine on heating. Evidence was obtained in support of the hypotheses that S-(methylseleno)cysteine is formed from a reaction between dimethyldiselenide and cysteine or cystine.

Selenium for preventing cancer

Science.gov (United States)

Vinceti, Marco; Dennert, Gabriele; Crespi, Catherine M; Zwahlen, Marcel; Brinkman, Maree; Zeegers, Maurice PA; Horneber, Markus; D'Amico, Roberto; Del Giovane, Cinzia

2015-01-01

Background This review is an update of the first Cochrane publication on selenium for preventing cancer (Dennert 2011). Selenium is a metalloid with both nutritional and toxicological properties. Higher selenium exposure and selenium supplements have been suggested to protect against several types of cancers. Objectives Two research questions were addressed in this review: What is the evidence for: an aetiological relation between selenium exposure and cancer risk in humans? andthe efficacy of selenium supplementation for cancer prevention in humans? Search methods We conducted electronic searches of the Cochrane Central Register of Controlled Trials (CENTRAL, 2013, Issue 1), MEDLINE (Ovid, 1966 to February 2013 week 1), EMBASE (1980 to 2013 week 6), CancerLit (February 2004) and CCMed (February 2011). As MEDLINE now includes the journals indexed in CancerLit, no further searches were conducted in this database after 2004. Selection criteria We included prospective observational studies (cohort studies including sub-cohort controlled studies and nested case-control studies) and randomised controlled trials (RCTs) with healthy adult participants (18 years of age and older). Data collection and analysis For observational studies, we conducted random effects meta-analyses when five or more studies were retrieved for a specific outcome. For RCTs, we performed random effects meta-analyses when two or more studies were available. The risk of bias in observational studies was assessed using forms adapted from the Newcastle-Ottawa Quality Assessment Scale for cohort and case-control studies; the criteria specified in the Cochrane Handbook for Systematic Reviews of Interventions were used to evaluate the risk of bias in RCTs. Main results We included 55 prospective observational studies (including more than 1,100,000 participants) and eight RCTs (with a total of 44,743 participants). For the observational studies, we found lower cancer incidence (summary odds ratio (OR) 0

21 CFR 573.920 - Selenium.

Science.gov (United States)

2010-04-01

... section, or as selenium yeast, as provided in paragraph (h) of this section. (c) It is added to feed as... months.” (h) Selenium yeast is a dried, non-viable yeast (Saccharomyces cerevisiae) cultivated in a fed-batch fermentation which provides incremental amounts of cane molasses and selenium salts in a manner...

Dietary selenium in the Glasgow area

International Nuclear Information System (INIS)

Cross, J.D.; Raie, R.M.; Smith, H.

1978-01-01

A typical diet for people in the Glasgow area is analysed and an estimate is made of the daily intake of selenium for the average person (234 μg). Meat, poultry and bread products contribute 65% of the total selenium consumed. There is a significant loss of selenium on cooking but the concentration in the diet is high compared with the estimated requirement. Selenium levels in prepared infant foods, artificial milk and natural milk are reported. Those infants on artificial milk feeds have a selenium intake equivalent to that of adults (3 μg/kg) while those on natural milk or prepared infant foods have an intake of 6 μg/kg. Adult and infant tissue selenium levels are established and are shown to be in equilibrium with the diet. There is no concentration in man as a result of his position at the top of the food chain. Sudden infant death cannot be related to selenium levels in human tissue or diet. (author)

Selenium: environmental significance, pollution, and biological treatment technologies.

Science.gov (United States)

Tan, Lea Chua; Nancharaiah, Yarlagadda V; van Hullebusch, Eric D; Lens, Piet N L

2016-01-01

Selenium is an essential trace element needed for all living organisms. Despite its essentiality, selenium is a potential toxic element to natural ecosystems due to its bioaccumulation potential. Though selenium is found naturally in the earth's crust, especially in carbonate rocks and volcanic and sedimentary soils, about 40% of the selenium emissions to atmospheric and aquatic environments are caused by various industrial activities such as mining-related operations. In recent years, advances in water quality and pollution monitoring have shown that selenium is a contaminant of potential environmental concern. This has practical implications on industry to achieve the stringent selenium regulatory discharge limit of 5μgSeL(-1) for selenium containing wastewaters set by the United States Environmental Protection Agency. Over the last few decades, various technologies have been developed for the treatment of selenium-containing wastewaters. Biological selenium reduction has emerged as the leading technology for removing selenium from wastewaters since it offers a cheaper alternative compared to physico-chemical treatments and is suitable for treating dilute and variable selenium-laden wastewaters. Moreover, biological treatment has the advantage of forming elemental selenium nanospheres which exhibit unique optical and spectral properties for various industrial applications, i.e. medical, electrical, and manufacturing processes. However, despite the advances in biotechnology employing selenium reduction, there are still several challenges, particularly in achieving stringent discharge limits, the long-term stability of biogenic selenium and predicting the fate of bioreduced selenium in the environment. This review highlights the significance of selenium in the environment, health, and industry and biotechnological advances made in the treatment of selenium contaminated wastewaters. The challenges and future perspectives are overviewed considering recent

Adaptive resource allocation for efficient patient scheduling

NARCIS (Netherlands)

Vermeulen, Ivan B.; Bohte, Sander M.; Elkhuizen, Sylvia G.; Lameris, Han; Bakker, Piet J. M.; La Poutré, Han

2009-01-01

Efficient scheduling of patient appointments on expensive resources is a complex and dynamic task. A resource is typically used by several patient groups. To service these groups, resource capacity is often allocated per group, explicitly or implicitly. Importantly, due to fluctuations in demand,

Selenium in aquatic biota inhabiting agricultural drains in the Salton Sea Basin, California

Science.gov (United States)

Saiki, Michael K.; Martin, Barbara A.; May, Thomas W.

2012-01-01

Resource managers are concerned that water conservation practices in irrigated farmlands along the southern border of the Salton Sea, Imperial County, California, could increase selenium concentrations in agricultural drainwater and harm the desert pupfish (Cyprinodon macularius), a federally protected endangered species. As part of a broader attempt to address this concern, we conducted a 3-year investigation to collect baseline information on selenium concentrations in seven agricultural drains inhabited by pupfish. We collected water, sediment, selected aquatic food-chain taxa (particulate organic detritus, filamentous algae, net plankton, and midge [Chironomidae] larvae), and two poeciliid fishes (western mosquitofish Gambusia affinis and sailfin molly Poecilia latipinna) for selenium determinations. The two fish species served as ecological surrogates for pupfish, which we were not permitted to sacrifice. Dissolved selenium ranged from 0.70 to 32.8 μg/L, with selenate as the major constituent. Total selenium concentrations in other environmental matrices varied widely among drains, with one drain (Trifolium 18) exhibiting especially high concentrations in detritus, 5.98–58.0 μg Se/g; midge larvae, 12.7–50.6 μg Se/g; mosquitofish, 13.2–20.2 μg Se/g; and mollies, 12.8–30.4 μg Se/g (all tissue concentrations are based on dry weights). Although toxic thresholds for selenium in fishes from the Salton Sea are still poorly understood, available evidence suggests that ambient concentrations of this element may not be sufficiently elevated to adversely affect reproductive success and survival in selenium-tolerant poeciliids and pupfish.

Selenium in aquatic biota inhabiting agricultural drains in the Salton Sea Basin, California.

Science.gov (United States)

Saiki, Michael K; Martin, Barbara A; May, Thomas W

2012-09-01

Resource managers are concerned that water conservation practices in irrigated farmlands along the southern border of the Salton Sea, Imperial County, California, could increase selenium concentrations in agricultural drainwater and harm the desert pupfish (Cyprinodon macularius), a federally protected endangered species. As part of a broader attempt to address this concern, we conducted a 3-year investigation to collect baseline information on selenium concentrations in seven agricultural drains inhabited by pupfish. We collected water, sediment, selected aquatic food-chain taxa (particulate organic detritus, filamentous algae, net plankton, and midge [Chironomidae] larvae), and two poeciliid fishes (western mosquitofish Gambusia affinis and sailfin molly Poecilia latipinna) for selenium determinations. The two fish species served as ecological surrogates for pupfish, which we were not permitted to sacrifice. Dissolved selenium ranged from 0.70 to 32.8 μg/L, with selenate as the major constituent. Total selenium concentrations in other environmental matrices varied widely among drains, with one drain (Trifolium 18) exhibiting especially high concentrations in detritus, 5.98-58.0 μg Se/g; midge larvae, 12.7-50.6 μg Se/g; mosquitofish, 13.2-20.2 μg Se/g; and mollies, 12.8-30.4 μg Se/g (all tissue concentrations are based on dry weights). Although toxic thresholds for selenium in fishes from the Salton Sea are still poorly understood, available evidence suggests that ambient concentrations of this element may not be sufficiently elevated to adversely affect reproductive success and survival in selenium-tolerant poeciliids and pupfish.

Resource Efficient Metal and Material Recycling

Science.gov (United States)

Reuter, Markus A.; van Schaik, Antoinette

Metals enable sustainability through their use and their recyclability. However, various factors can affect the Resource Efficiency of Metal Processing and Recycling. Some typical factors that enable Resource Efficiency include and arranged under the drivers of sustainability: Environment (Maximize Resource Efficiency — Energy, Recyclates, Materials, Water, Sludges, Emissions, Land); Economic Feasibility (BAT & Recycling Systems Simulation / Digitalization, Product vis-à-vis Material Centric Recycling); and Social — Licence to Operate (Legislation, consumer, policy, theft, manual labour.). In order to realize this primary production has to be linked systemically with typical actors in the recycling chain such as Original Equipment Manufacturers (OEMs), Recyclers & Collection, Physical separation specialists as well as process metallurgical operations that produce high value metals, compounds and products that recycle back to products. This is best done with deep knowledge of multi-physics, technology, product & system design, process control, market, life cycle management, policy, to name a few. The combination of these will be discussed as Design for Sustainability (DfS) and Design for Recycling (DfR) applications.

Aquatic Life Criterion - Selenium

Science.gov (United States)

Documents pertaining to the 2016 Acute and Chronic Ambient Aquatic Life Water Quality Criteria for Selenium (Freshwater). These documents include what the safe levels of Selenium are in water for the majority of species.

Optimised selenium enrichment of Artemia sp. feed to improve red drum (Sciaenops ocellatus) larvae rearing.

Science.gov (United States)

Juhász, Péter; Lengyel, Szvetlana; Udvari, Zsolt; Sándor, Alex Nagy; Stündl, László

2017-09-01

Selenium is an essential microelement for the normal functioning of life processes. Moreover, it is a component of enzymes with antioxidant effects. However, it has the smallest window of any micronutrient between requirement and toxicity. Selenium is a regularly used element in fish feeds; moreover, enriching zooplankton with selenium to rear larvae is also a well-known technology. It is accepted that the most common starter foods of fish larvae, natural rotifers contain the smallest dosage of selenium, but providing selenium enriched Artemia sp. instead could increase survival and growth rate of fish. However, no such references are available for the red drum (Sciaenops ocellatus) larvae. Therefore, in this study, Artemia sp. was enriched with nano-selenium of verified low toxicity and easy availability in 5 treatments (1, 5, 10, 50, 100 mg/l Se), and then, fish larvae were fed with four of these enriched Artemia stocks (1, 5, 10, 50 mg/l Se) and a control group. At the end of the 9-day-long experiment, survival rate (S) and growth parameters (SL, W, K-factor, SGR) of fish larvae were calculated as well as their selenium retention and glutathione peroxidase enzyme activity were analysed. It was revealed that a moderate level of selenium enrichment (~4 mg/kg dry matter) of Artemia sp. positively influences the rearing efficiency (i.e. survival and growth) of fish larvae, but higher dosages of selenium could cause adverse effects.

Electrochemical preconcentration and hydride generation methods for trace determination of selenium by atomic absorption spectrometry

International Nuclear Information System (INIS)

Bye, R.

1986-01-01

The use of atomic absorption spectrometry in combination with two different preconcentration/separation techniques for the determination of trace concentrations of selenium is described. Electrochemical preconcentration onto a platinum electrode with a subsequent atomization of selenium is discussed briefly. Several parameters are considered such as the presence of depolarizers, and the temperature of the electrolyzed solutions. Special attention is payed to the efficiency of the atomization step, and a method to improve this is proposed. Applications of the technique to real samples are also reported. Secondly, the separation of the selenium as the volatile selenium hydride from the sample solution is considered. Several papers in this thesis deal with commonly occurring interferants as nickel and copper and with ways of minimizing or avoiding the interferring effects, whereas other papers relate to more theoretical aspects of the hydride generation process. New methods for the determination of selenium in technical samples with high contents of nickel and copper are also presented

Selenium in Graves' disease

Directory of Open Access Journals (Sweden)

Jadwiga Kryczyk

2013-05-01

Full Text Available The aim of this study was to present the current state of knowledge of the role of selenium in Graves’ disease. Recently, in the pathogenesis and course of this autoimmune disease, more attention has been paid to the relationship between oxidative stress and the antioxidant system, where selenium compounds play an important role. The thyroid is the organ with the highest selenium concentration in the human body. Selenium compounds, having antioxidant properties, protect thyrocytes against the destructive effects of reactive oxygen species (ROS, which are generated during the synthesis of thyroid hormones. Therefore, strengthening the body’s defense mechanisms, which protect against the formation and activity of ROS during medical treatment of Graves’ disease patients, may be an effective adjuvant in commonly used methods of therapy.

Does selenium supplementation affect thyroid function?

DEFF Research Database (Denmark)

Winther, Kristian Hillert; Bonnema, Steen Joop; Cold, Frederik

2015-01-01

OBJECTIVE: Selenium is present in the active site of proteins important for thyroid hormone synthesis and metabolism. The objective of this study is to investigate the effect of selenium supplementation in different doses on thyroid function, under conditions of suboptimal dietary selenium intake....... DESIGN: The Danish PREvention of Cancer by Intervention with SElenium pilot study (DK-PRECISE) is a randomized, double-blinded, placebo-controlled trial. A total of 491 males and females aged 60-74 years were randomized to 100 μg (n=124), 200 μg (n=122), or 300 μg (n=119) selenium-enriched yeast......=0.015), respectively, per 100 μg/day increase, with insignificant differences between 6 months and 5 years. No significant effects were found for FT3 and FT3:FT4 ratio. CONCLUSIONS: In euthyroid subjects, selenium supplementation minutely and dose-dependently affects thyroid function, when compared...

Acute selenium poisoning in lambs

Energy Technology Data Exchange (ETDEWEB)

Gabbedy, B J; Dickson, J

1969-10-01

An outbreak of sodium selenite poisoning is reported in which 180 of 190 six-weeks-old lambs died. The estimated dose rate of the selenium was 6.4 mg/kg body weight. Liver concentrations of selenium at the time of poisoning averaged 64 ppM and 15 days later liver and kidney concentrations of selenium averaged 26 ppM and 7.4 ppM respectively.

Total selenium and selenium species in irrigation drain inflows to the Salton Sea, California, April and July 2007

Science.gov (United States)

May, Thomas W.; Walther, Michael J.; Saiki, Michael K.; Brumbaugh, William G.

2007-01-01

This report presents the results for two sampling periods during a 4-year monitoring survey to provide a characterization of selenium concentrations in selected irrigation drains flowing into the Salton Sea, California. Total selenium, selenium species, and total suspended solids were determined in water samples, and total selenium was determined in sediment, detritus, and biota that included algae, plankton, midge larvae (family, Chironomidae), and two fish species-western mosquitofish (Gambusia affinis), and sailfin molly (Poecilia latipinna). In addition, sediments were analyzed for percent total organic carbon and particle size. Total selenium concentrations in water for both sampling periods ranged from 1.43 to 47.1 micrograms per liter, predominately as selenate, which is typical of waters leached out of selenium-contaminated marine shales under alkaline and oxidizing conditions. Total selenium concentrations ranged from 0.88 to 20.2 micrograms per gram in biota, and from 0.15 to 28.9 micrograms per gram in detritus and sediment.

Selenium-regulated hierarchy of human selenoproteome in cancerous and immortalized cells lines.

Science.gov (United States)

Touat-Hamici, Zahia; Bulteau, Anne-Laure; Bianga, Juliusz; Jean-Jacques, Hélène; Szpunar, Joanna; Lobinski, Ryszard; Chavatte, Laurent

2018-04-13

Selenoproteins (25 genes in human) co-translationally incorporate selenocysteine using a UGA codon, normally used as a stop signal. The human selenoproteome is primarily regulated by selenium bioavailability with a tissue-specific hierarchy. We investigated the hierarchy of selenoprotein expression in response to selenium concentration variation in four cell lines originating from kidney (HEK293, immortalized), prostate (LNCaP, cancer), skin (HaCaT, immortalized) and liver (HepG2, cancer), using complementary analytical methods. We performed (i) enzymatic activity, (ii) RT-qPCR, (iii) immuno-detection, (iv) selenium-specific mass spectrometric detection after non-radioactive 76 Se labeling of selenoproteins, and (v) luciferase-based reporter constructs in various cell extracts. We characterized cell-line specific alterations of the selenoproteome in response to selenium variation that, in most of the cases, resulted from a translational control of gene expression. We established that UGA-selenocysteine recoding efficiency, which depends on the nature of the SECIS element, dictates the response to selenium variation. We characterized that selenoprotein hierarchy is cell-line specific with conserved features. This analysis should be done prior to any experiments in a novel cell line. We reported a strategy based on complementary methods to evaluate selenoproteome regulation in human cells in culture. Copyright © 2018 Elsevier B.V. All rights reserved.

Total selenium and selenium species in irrigation drain inflows to the Salton Sea, California, April and July 2008

Science.gov (United States)

May, Thomas W.; Walther, Michael J.; Saiki, Michael K.; Brumbaugh, William G.

2009-01-01

This report presents the results for two sampling periods (April 2008 and July 2008) during a 4-year monitoring program to characterize selenium concentrations in selected irrigation drains flowing into the Salton Sea, California. Total selenium, selenium species (dissolved selenite, selenate, organoselenium), and total suspended solids were determined in water samples and total selenium was determined in water column particulates and in sediment, detritus, and biota that included algae, plankton, midge larvae (family, Chironomidae), and two fish species - western mosquitofish (Gambusia affinis) and sailfin molly (Poecilia latipinna). In addition, sediments were analyzed for percent total organic carbon and particle size. Mean total selenium concentrations in water for both sampling periods ranged from 1.93 to 44.2 micrograms per liter, predominately as selenate, which is typical of waters where selenium is leached out of selenium-containing marine shales and associated soils under alkaline and oxidizing conditions. Total selenium concentrations (micrograms per gram dry weight) ranged as follows: algae, 0.75 to 3.39; plankton, 0.88 to 4.03; midges, 2.52 to 44.3; fish, 3.37 to 18.9; detritus, 1.11 to 13.6; sediment, 0.11 to 8.93.

Mercury and selenium relationship in a tropical estuarine fish

Directory of Open Access Journals (Sweden)

Ana Carolina Pizzochero

2015-11-01

Full Text Available Aquatic systems have been considered as final sinks for persistent and bioaccumulative toxicants (PBTs, such as metals and organohalogen compounds. Among the trace elements, non-essential metals deserve special attention due to their toxicity. In this context, mercury (Hg should be highlighted due to its toxic effects, which comprise neurotoxicity, nephrotoxicity, hepatotoxicity, genotoxicity, among others. Several studies have highlighted the selenium-mediated methylmercury detoxification process, via mercury selenide formation in tissues of marine vertebrates. Despite being an essential element, selenium may also be toxic in high concentrations. This study focused on Guanabara Bay (GB, a heavily polluted urban estuary in Rio de Janeiro state (Brazil, where the whitemouth croaker (Micropogonias furnieri provides a valuable fishery resource. Therefore, hepatic (Hg and Se and muscular (Hg concentrations of these elements were determined in GB whitemouth croakers. Mercury and selenium measurements were performed by cold vapor atomic absorption spectrometry (CV-AAS and electrothermal AAS (ET-AAS, respectively. Total mercury (THg concentrations in muscle (n=19 ranged from 184.9 to 858.6 (ng/g, while in liver they varied from 11.05 to 1188 (ng/g. Hepatic selenium concentrations ranged from 7820 to 40085 (ng/g. The hepatic Se:THg molar ratio ranged from 40,8 to 3102,5. The results showed a significant correlation between hepatic mercury and selenium levels, but the molar ratio suggests the absence of mercury selenide formation. Some of the Se concentrations found were above the threshold level for freshwater fish (12000 ng/g; however, it is not yet clear if these concentrations are toxic for marine fish as well. More studies are necessary for evaluating the impact of such exposure in fish from Guanabara Bay.

The Cultivation and SeleniumEnrichment of SeleniumEnriched Earthworm

Directory of Open Access Journals (Sweden)

SUN Xiao-fei

2014-12-01

Full Text Available As a bio-carrier, Eisenia fetida was fed with cow dung that added with sodium selenite in order to transfer inorganic selenium(Se into organic selenium. Targeting on survival rate and selenium content, the effects of five Se concentrations(0, 20, 40, 60, 80, 100 mg·kg-1 and four cultivation periods(15, 30, 45, 60 don earthworm growth and Se contents were investigated. The cultivation method with high survival rate, high Se content of earthworm and short breeding time would be screened out. The experimental results showed that the earthworm survival rate decreased and the Se content in earthworm increased with the increase of Se application and the extension of breeding time. The most optimummethod was screened out when the Se concentration was 80 mg·kg-1 and the cultivation period was 45 days, Se content in earthworm was up to 33.25 mg·kg-1.

Trace Element Analysis of Selenium

International Nuclear Information System (INIS)

Soliman, M.S.A.

2010-01-01

The present thesis divided into four chapters as follows:Chapter (1):This chapter contains an introduction on different oxidation states of organic and inorganic species for selenium in environmental and biological samples, the process for separation of selenium from these samples and the importance of selenium as a component for these samples. Also gives notes about the techniques which are used in the elemental analysis for selenium species and the detection limits for selenium in these techniques, selenium species in human body and the importance of these species in protecting the body from the different types of cancer and the sources of selenium in environmental samples (soil and water) and distribution levels of selenium in these samples.Chapter (2):This chapter is divided into two parts :The first part deals with the sample collection process for environmental samples (underground water, soil) and the wet digestion ( microwave digestion ) process of soil samples. It also contains the theory of work of the closed microwave digestion system.The second part contains detailed information concerning the theoretical considerations of the used analytical techniques. These techniques include Hydride generation - Atomic Absorption Spectrometer (HG-AAS), Inductively Coupled Plasma Mass Spectrometer (ICP-MS) and Neutron Activation Analysis (NAA).Chapter (3): This chapter includes the methods of sampling, sample preparation, and sample digesition. The measures of quality assurance are disscused in this chapter. It describes in details the closed microwave digestion technique and the analytical methods used in this study which are present in Central Laboratory for Elemental and Isotopic Analysis (CLEIA) and the Egypt Second Research Reactor (ETRR-2). The described techniques are Atomic Absorption Spectrometer (AAS 6 vario, Analytical Jena GmbH, Germany), JMS-PLASMAX2 Mass Spectrometer (ICP-MS) and the Egypt Second Research Reactor (NAA).

Acute selenium poisoning in cattle

Energy Technology Data Exchange (ETDEWEB)

Shortridge, E H; O' Hara, P J; Marshall, P M

1971-01-01

Three hundred and seventy-six (67%) of 557 calves of approximately 150-200 kg live-weight died following subcutaneous injection of a solution containing 100 mg selenium as sodium selenite. Eight per cent of the 254 heifer calves and 56% of the 303 steers died. The calves had endured the stress of being weaned twice and held in stockyards twice as well as encountering wet weather during the 4 days before receiving the selenium. The heifer calves were also vaccinated with Br. abortus strain 19 vaccine at the same time as receiving the selenium. The clinical signs and pathological findings of circulatory failure and myocardial damage were similar to those previously reported in acute selenium poisoning.

Selenium Utilization Strategy by Microalgae

Directory of Open Access Journals (Sweden)

Hiroya Araie

2009-11-01

Full Text Available The diversity of selenoproteins raises the question of why so many life forms require selenium. Selenoproteins are found in bacteria, archaea, and many eukaryotes. In photosynthetic microorganisms, the essential requirement for selenium has been reported in 33 species belonging to six phyla, although its biochemical significance is still unclear. According to genome databases, 20 species are defined as selenoprotein-producing organisms, including five photosynthetic organisms. In a marine coccolithophorid, Emiliania huxleyi (Haptophyta, we recently found unique characteristics of selenium utilization and novel selenoproteins using 75Se-tracer experiments. In E. huxleyi, selenite, not selenate, is the main substrate used and its uptake is driven by an ATP-dependent highaffinity, active transport system. Selenite is immediately metabolized to low-molecular mass compounds and partly converted to at least six selenoproteins, named EhSEP1–6. The most (EhSEP2 and second-most abundant selenoproteins (EhSEP1 are disulfide isomerase (PDI homologous protein and thioredoxin reductase (TR 1, respectively. Involvement of selenium in PDI is unique in this organism, while TR1 is also found in other organisms. In this review, we summarize physiological, biochemical, and molecular aspects of selenium utilization by microalgae and discuss their strategy of selenium utilization.

Selenistasis: Epistatic Effects of Selenium on Cardiovascular Phenotype

Directory of Open Access Journals (Sweden)

Joseph Loscalzo

2013-01-01

Full Text Available Although selenium metabolism is intricately linked to cardiovascular biology and function, and deficiency of selenium is associated with cardiac pathology, utilization of selenium in the prevention and treatment of cardiovascular disease remains an elusive goal. From a reductionist standpoint, the major function of selenium in vivo is antioxidant defense via its incorporation as selenocysteine into enzyme families such as glutathione peroxidases and thioredoxin reductases. In addition, selenium compounds are heterogeneous and have complex metabolic fates resulting in effects that are not entirely dependent on selenoprotein expression. This complex biology of selenium in vivo may underlie the fact that beneficial effects of selenium supplementation demonstrated in preclinical studies using models of oxidant stress-induced cardiovascular dysfunction, such as ischemia-reperfusion injury and myocardial infarction, have not been consistently observed in clinical trials. In fact, recent studies have yielded data that suggest that unselective supplementation of selenium may, indeed, be harmful. Interesting biologic actions of selenium are its simultaneous effects on redox balance and methylation status, a combination that may influence gene expression. These combined actions may explain some of the biphasic effects seen with low and high doses of selenium, the potentially harmful effects seen in normal individuals, and the beneficial effects noted in preclinical studies of disease. Given the complexity of selenium biology, systems biology approaches may be necessary to reach the goal of optimization of selenium status to promote health and prevent disease.

Plasma Selenium Concentrations Are Sufficient and Associated with Protease Inhibitor Use in Treated HIV-Infected Adults123

Science.gov (United States)

Hileman, Corrilynn O; Dirajlal-Fargo, Sahera; Lam, Suet Kam; Kumar, Jessica; Lacher, Craig; Combs, Gerald F; McComsey, Grace A

2015-01-01

and higher selenium may have implications for ART allocation, especially in resource-limited countries. Also, it appears that statin therapy may increase selenium concentrations; however, larger studies are necessary to confirm this finding. This trial was registered at clinicaltrials.gov as NCT01218802. PMID:26269240

Total selenium and selenium species in irrigation drain inflows to the Salton Sea, California, October 2008 and January 2009

Science.gov (United States)

May, Thomas W.; Walther, Michael J.; Saiki, Michael K.; Brumbaugh, William G.

2009-01-01

This report presents the results for two sampling periods (October 2008 and January 2009) during a 4-year monitoring program to characterize selenium concentrations in selected irrigation drains flowing into the Salton Sea, California. Total selenium, selenium species (dissolved selenite, selenate, organoselenium), and total suspended solids were determined in water samples. Total selenium also was determined in water column particulates and in sediment, detritus, and biota that included algae, plankton, midge larvae (family, Chironomidae), and two fish species (western mosquitofish, Gambusia affinis, and sailfin molly, Poecilia latipinna). In addition, sediments were analyzed for percent total organic carbon and particle size. Mean total selenium concentrations in water for both sampling periods ranged from 1.00 to 33.6 micrograms per liter, predominately as selenate, which is typical of waters where selenium is leached out of selenium-containing marine shales and associated soils under alkaline and oxidizing conditions. Total selenium concentrations (micrograms per gram dry weight) ranged as follows: algae, 1.52 to 8.26; plankton, 0.79 to 3.66; midges, 2.68 to 50.6; fish, 3.09 to 30.4; detritus, 1.78 to 58.0; and sediment, 0.42 to 10.0.

Total selenium and selenium species in irrigation drain inflows to the Salton Sea, California, October 2007 and January 2008

Science.gov (United States)

May, Thomas W.; Walther, Michael J.; Saiki, Michael K.; Brumbaugh, William G.

2008-01-01

This report presents the results for two sampling periods (October 2007 and January 2008) during a 4-year monitoring program to characterize selenium concentrations in selected irrigation drains flowing into the Salton Sea, California. Total selenium, selenium species (selenite, selenate, organoselenium), and total suspended solids were determined in water samples, and total selenium was determined in sediment, detritus, and biota that included algae, plankton, midge larvae (family, Chironomidae), and two fish species?western mosquitofish (Gambusia affinis) and sailfin molly (Poecilia latipinna). In addition, sediments were analyzed for percent total organic carbon and particle size. Mean total selenium concentrations in water for both sampling periods ranged from 0.97 to 64.5 micrograms per liter, predominately as selenate, which is typical of waters where selenium is leached out of selenium-containing marine shales and associated soils under alkaline and oxidizing conditions. Total selenium concentrations (micrograms per gram dry weight) ranged as follows: algae, 0.95 to 5.99; plankton, 0.15 to 19.3; midges, 1.39 to 15.4; fish, 3.71 to 25.1; detritus, 0.85 to 21.7; sediment, 0.32 to 7.28.

Low plasma selenium concentrations in critically ill children: the interaction effect between inflammation and selenium deficiency

Science.gov (United States)

2014-01-01

Introduction Low plasma selenium concentrations are frequent in critically ill patients. However, whether this is due to systemic inflammation, a deficient nutritional state or both is still not clear. We aimed to determine the factors associated with low plasma selenium in critically ill children while considering the inflammatory response and nutritional status. Method A prospective study was conducted in 173 children (median age 34 months) with systemic inflammatory response who had plasma selenium concentrations assessed 48 hours after admission and on the 5th day of ICU stay. The normal reference range was 0.58 μmol/L to 1.6 μmol/L. The outcome variable was ‘low plasma selenium’, which was defined as plasma selenium values below the distribution median during this period. The main explanatory variables were age, malnutrition, sepsis, C-reactive protein (CRP), and clinical severity scores. The data were analyzed using a Binomial Generalized Estimating Equations model, which includes the correlation between admission and 5th day responses. Results Malnutrition and CRP were associated with low plasma selenium. The interaction effect between these two variables was significant. When CRP values were less than or equal to 40 mg/L, malnutrition was associated with low plasma selenium levels (odds ratio (OR) = 3.25, 95% confidence interval (CI) 1.39 to 7.63, P = 0.007; OR = 2.98, 95% CI 1.26 to 7.06, P = 0.013; OR = 2.49, 95% CI 1.01 to 6.17, P = 0.049, for CRP = 10, 20 and 40 mg/L, respectively). This effect decreased as CRP concentrations increased and there was loose significance when CRP values were >40 mg/L. Similarly, the effect of CRP on low plasma selenium was significant for well-nourished patients (OR = 1.13; 95% CI 1.06 to 1.22, P selenium. This interaction should be considered when interpreting plasma concentrations as an index of selenium status in patients with systemic inflammation as well as in the decision

Selenium accumulation and metabolism in algae.

Science.gov (United States)

Schiavon, Michela; Ertani, Andrea; Parrasia, Sofia; Vecchia, Francesca Dalla

2017-08-01

Selenium (Se) is an intriguing element because it is metabolically required by a variety of organisms, but it may induce toxicity at high doses. Algae primarily absorb selenium in the form of selenate or selenite using mechanisms similar to those reported in plants. However, while Se is needed by several species of microalgae, the essentiality of this element for plants has not been established yet. The study of Se uptake and accumulation strategies in micro- and macro-algae is of pivotal importance, as they represent potential vectors for Se movement in aquatic environments and Se at high levels may affect their growth causing a reduction in primary production. Some microalgae exhibit the capacity of efficiently converting Se to less harmful volatile compounds as a strategy to cope with Se toxicity. Therefore, they play a crucial role in Se-cycling through the ecosystem. On the other side, micro- or macro-algae enriched in Se may be used in Se biofortification programs aimed to improve Se content in human diet via supplementation of valuable food. Indeed, some organic forms of selenium (selenomethionine and methylselenocysteine) are known to act as anticarcinogenic compounds and exert a broad spectrum of beneficial effects in humans and other mammals. Here, we want to give an overview of the developments in the current understanding of Se uptake, accumulation and metabolism in algae, discussing potential ecotoxicological implications and nutritional aspects. Copyright © 2017 Elsevier B.V. All rights reserved.

Resource Efficiency. What does it mean and why is it relevant? Policy Brief

Energy Technology Data Exchange (ETDEWEB)

Jansen, J.C. [ECN Policy Studies, Petten (Netherlands)

2013-04-15

The European Commission has launched a Resource-Efficient Europe as one of its seven flagship initiatives under the Europe 2020 Strategy and has published the document 'Roadmap to a Resource-Efficient Europe'. The Roadmap specifies a proposed pathway to action for a resource efficient Europe. This document sets out to describe the essence of the resource efficiency concept and to sketch the relevance of EU resource efficiency policy for application at EU member state level with special reference to the Netherlands. The following questions will be addressed: What is resource efficiency?; How does it relate to sustainability and environmental footprint?; What is the relevance of EU resource efficiency policy for the member states?; Which aspects of resource efficiency are relevant for the Netherlands?; and To what extent is resource efficiency reflected in current Dutch policies?.

Joint refinery selenium treatability study

International Nuclear Information System (INIS)

Meyer, C.L.; Folwarkow, S.

1993-01-01

The San Francisco Regional Water Quality Control Board recently established mass limits on discharges of selenium to the San Francisco Bay from several petroleum refineries. The refineries had been working independently to develop control strategies, including both source control and treatment options, for removal of selenium from their discharges. By January 1992, over fifty different combinations of treatment technologies, wastewater streams, and pretreatment steps had been investigated to determine their effectiveness and feasibility as selenium removal processes. No treatment process studied could achieve the required mass limits without serious negative environmental consequences, such as generation of large amounts of hazardous sludge. To better facilitate the development of a feasible selenium treatment process, the six Bay Area refineries shared results of their studies and identified several technologies that, with further work, could be developed further. This additional work is currently being carried out as part of a joint selenium treatability study sponsored by the Western States Petroleum Association. A review of the previous source control and treatment studies, along with a description of the current treatability studies will be discussed

Selenium content of foods purchased or produced in Ohio.

Science.gov (United States)

Snook, J T; Kinsey, D; Palmquist, D L; DeLany, J P; Vivian, V M; Moxon, A L

1987-06-01

Approximately 450 samples of about 100 types of foods consumed by rural and urban Ohioans were analyzed for selenium. Meat, dairy products, eggs, and grain products produced in Ohio have considerably lower selenium content than corresponding products produced in high selenium areas, such as South Dakota. Retail Ohio foods with interregional distribution tended to be higher in selenium content than corresponding foods produced in Ohio. Best sources of selenium in Ohio foods commonly consumed were meat and pasta products. Poor sources of selenium were fruits, most vegetables, candies, sweeteners, and alcoholic and nonalcoholic beverages. Establishment of an accurate data base for selenium depends on knowledge of the interregional distribution of foods, the selenium content of foods at their production site, and the selenium content of foods with wide local distribution.

Recovery of stream communities from experimental selenium exposure

Energy Technology Data Exchange (ETDEWEB)

Swift, M.C.; Kuklinskal, B.; Ferkull, K. [Univ. of Minnesota, Monticello, MN (United States); Allen, K.N.; Hermanutz, R.O.; Roush, T.H.; Hedtke, S.F. [Environmental Protection Agency, Duluth, MN (United States). Environmental Research Lab.

1994-12-31

The effects of selenium on stream communities and their recovery from those effects were studied at MERS from 1987--1991. Selenium was dosed into two replicate streams each at concentrations of 30, 10, 2.5 and 0 (control) {mu}g L{sup {minus}1} for 18, 30, and 12 months, respectively. Recovery was monitored for three (30) or two (1 0, 2.5) years following cessation of selenium dosing. Selenium rapidly accumulated in the sediment, plants, macroinvertebrates and fish during dosing. Selenium concentrations in sediment, macroinvertebrates, and plants were as high as 2X--4X, 2X--4X, and 1X--1OX the dosed concentration in the 30, 10, and 2.5 treatments, respectively. Selenium decreased relatively rapidly following cessation of dosing. By two years after dosing ceased, selenium concentrations in plants and macroinvertebrates were little different from the controls; selenium in sediment from the 30 and 10 streams was still higher than in the control streams two years after dosing ceased. The macroinvertebrate community changed little during the dosing and recovery period. Commonly used indices of community structure showed no effect of selenium dosing. The isopod Asellus and oligochaetes in the family Tubificidae decreased rapidly following the onset of selenium dosing; their recovery following cessation of dosing was slow.

Determination of selenium via the fluorescence quenching effect of selenium on hemoglobin-catalyzed peroxidative reaction.

Science.gov (United States)

Chen, Ya-Hong; Zhang, Ya-Nan; Tian, Feng-Shou

2015-05-01

A new method for the determination of selenium based on its fluorescence quenching on the hemoglobin-catalyzed reaction of H2 O2 and l-tyrosine has been established. The effect of pH, foreign ions and the optimization of variables on the determination of selenium was examined. The calibration curve was found to be linear between the fluorescence quenching (F0 /F) and the concentration of selenium within the range of 0.16-4.00 µg/mL. The detection limit was 1.96 ng/mL and the relative standard deviation was 3.14%. This method can be used for the determination of selenium in Se-enriched garlic bulbs with satisfactory results. Copyright © 2014 John Wiley & Sons, Ltd.

Distribution and mode of occurrence of selenium in US coals

Science.gov (United States)

Coleman, L.; Bragg, L.J.; Finkelman, R.B.

1993-01-01

Selenium excess and deficiency have been established as the cause of various health problems in man and animals. Combustion of fossil fuels, especially coal, may be a major source of the anthropogenic introduction of selenium in the environment. Coal is enriched in selenium relative to selenium's concentration in most other rocks and relative to selenium in the Earth's crust. Data from almost 9,000 coal samples have been used to determine the concentration and distribution of selenium in US coals. The geometric mean concentration of selenium in US coal is 1.7 ppm. The highest mean selenium value (geometric mean 4.7 ppm) is in the Texas Region. Atlantic Coast (Virginia and North Carolina) and Alaska coals have the lowest geometric means (0.2 and 0.42 ppm, respectively). All western coal regions have mean selenium concentrations of less than 2.0 ppm. In contrast, all coal basins east of the Rocky Mountains (except for several small basins in Rhode Island, Virginia, and North Carolina) have mean selenium values of 1.9 or greater. Generally, variations in selenium concentration do not correlate with variations in ash yield, pyritic sulphur, or organic sulphur concentrations. This may be the result of multiple sources of selenium; however, in some non-marine basins with restricted sources of selenium, selenium has positive correlations with other coal quality parameters. Selenium occurs in several forms in coal but appears to be chiefly associated with the organic fraction, probably substituting for organic sulphur. Other important forms of selenium in coal are selenium-bearing pyrite, selenium-bearing galena, and lead selenide (clausthalite). Water-soluble and ion-exchangeable selenium also have been reported. ?? 1993 Copyright Science and Technology Letters.

Acute exposure to selenium disrupts associative conditioning and long-term memory recall in honey bees (Apis mellifera).

Science.gov (United States)

Burden, Christina M; Elmore, Christopher; Hladun, Kristen R; Trumble, John T; Smith, Brian H

2016-05-01

A plethora of toxic compounds - including pesticides, heavy metals, and metalloids - have been detected in honey bees (Apis mellifera) and their colonies. One such compound is selenium, which bees are exposed to by consuming nectar and pollen from flowers grown in contaminated areas. Though selenium is lethal at high concentrations, sublethal exposure may also impair honey bees' ability to function normally. Examining the effect of selenium exposure on learning and memory provides a sensitive assay with which to identify sublethal effects on honey bee health and behavior. To determine whether sublethal selenium exposure causes learning and memory deficits, we used proboscis extension reflex conditioning coupled with recall tests 30min and 24h post-conditioning. We exposed forager honey bees to a single sublethal dose of selenium, and 3h later we used an olfactory conditioning assay to train the bees to discriminate between one odor associated with sucrose-reinforcement and a second unreinforced odor. Following conditioning we tested short- and long-term recall of the task. Acute exposure to as little as 1.8ng of an inorganic form of selenium (sodium selenate) before conditioning caused a reduction in behavioral performance during conditioning. And, exposure to 18ng of either an inorganic form (sodium selenate) or an organic form (methylseleno-l-cysteine) of selenium caused a reduction in the bees' performance during the long-term recall test. These concentrations of selenium are lower than those found in the nectar of plants grown in selenium-contaminated soil, indicating that even low-grade selenium toxicity produces significant learning and memory impairments. This may reduce foragers' ability to effectively gather resources for the colony or nurse bees' ability to care for and maintain a healthy colony. Copyright © 2016. Published by Elsevier Inc.

The relationship between selenium and gastric cancer

International Nuclear Information System (INIS)

Shi Kuixiong; Ma Guansheng; Zhang Tingyu; Cheng Wufeng; Mao Dajuan; Pan Bixia; Xu Xiuxian

1993-01-01

Both sodium selenite and selenium yeast were chosen to block the MNNG mutagenesis. The inhibition rates were 66.5% and 37.9% respectively. The selenium levels in hair, serum and gastric juice, and the contents of nitrosamine in gastric juice were also determined. The results showed that the selenium levels were SG > CAG and Dys > GC (p CAG, Dyas and GC (p < 0.05). 19 cases of CAG patients treated with selenium yeast and 16 cases of the control were observed. After 10 weeks, the selenium levels in serum for the treated group were significantly increased. The symptoms of CAG patients seemed to be alleviated

Loss of selenium-binding protein 1 decreases sensitivity to clastogens and intracellular selenium content in HeLa cells

Science.gov (United States)

Selenium-binding protein 1 (SBP1) is not a selenoprotein but structurally binds selenium. Loss of SBP1 during carcinogenesis usually predicts poor prognosis. Because genome instability is a hallmark of cancer, we hypothesized that loss of SBP1 modulates cellular selenium content and the response of ...

Selenium plating of aluminium and nickel surfaces

International Nuclear Information System (INIS)

Qureshi, N.; Shams, N.; Kamal, A.; Ashraf, A.

1993-01-01

Selenium exhibits photovoltaic and photoconductive properties. This makes selenium useful in the production of photocells, exposure meters for photographic use, in solar cells, etc. In commerce, selenium coated surfaces are extensively used as photo receptive drums in the xerography machines for reproducing documents. Laboratory experiments were designed to obtain selenium plating on different materials. Of the various electrodes tested for cathodic deposition, anodized aluminum and nickel plated copper were found to give good results. (author)

Is selenium supplementation in autoimmune thyroid diseases justified?

Science.gov (United States)

Winther, Kristian H; Bonnema, Steen J; Hegedüs, Laszlo

2017-10-01

This review provides an appraisal of recent evidence for or against selenium supplementation in patients with autoimmune thyroid diseases, and discusses possible effect mechanisms. Epidemiological data suggest an increased prevalence of autoimmune thyroid diseases under conditions of low dietary selenium intake. Two systematic reviews have evaluated controlled trials among patients with autoimmune thyroiditis and report that selenium supplementation decreases circulating thyroid autoantibodies. The immunomodulatory effects of selenium might involve reducing proinflammatory cytokine release. However, clinically relevant effects of selenium supplementation, including improvement in quality of life, are more elusive. In Graves' disease, some, but not all, trials indicate that adjuvant selenium supplementation enhances the restoration of biochemical euthyroidism, and might benefit patients with mild Graves' orbitopathy. The use of selenium supplementation as adjuvant therapy to standard thyroid medication may be widespread, but a growing body of evidence yields equivocal results. The available evidence from trials does not support routine selenium supplementation in the standard treatment of patients with autoimmune thyroiditis or Graves' disease. However, correction of moderate to severe selenium deficiency may offer benefits in preventing, as well as treating, these disorders. Molecular mechanisms have been proposed, but further studies are needed.

High-Resolution Imaging of Selenium in Kidneys: A Localized Selenium Pool Associated with Glutathione Peroxidase 3

OpenAIRE

Malinouski, Mikalai; Kehr, Sebastian; Finney, Lydia; Vogt, Stefan; Carlson, Bradley A.; Seravalli, Javier; Jin, Richard; Handy, Diane E.; Park, Thomas J.; Loscalzo, Joseph; Hatfield, Dolph L.; Gladyshev, Vadim N.

2012-01-01

Aim: Recent advances in quantitative methods and sensitive imaging techniques of trace elements provide opportunities to uncover and explain their biological roles. In particular, the distribution of selenium in tissues and cells under both physiological and pathological conditions remains unknown. In this work, we applied high-resolution synchrotron X-ray fluorescence microscopy (XFM) to map selenium distribution in mouse liver and kidney. Results: Liver showed a uniform selenium distributio...

Polygeneration and efficient use of natural resources

Energy Technology Data Exchange (ETDEWEB)

Serra, Luis M.; Lozano, Miguel-Angel; Ramos, Jose [GITSE-I3A, Department of Mechanical Engineering, University of Zaragoza, CPS de Ingenieros, Maria de Luna, 3, 5018 Zaragoza (Spain); Ensinas, Adriano V.; Nebra, Silvia A. [Energy Department, State University of Campinas, Faculdade de Engenharia Mecanica, Cidade Universitaria Zeferino Vaz-Barao Geraldo, Campinas (Brazil)

2009-05-15

The consumption of natural resources has been increasing continuously during recent decades, due to the growing demand caused by both the economic and the demographic rise of global population. Environmental overloads that endanger the survival of our civilization and the sustainability of current life support systems are caused by the increased consumption of natural resources - particularly water and energy - which are essential for life and for the socio-economic development of societies. While not yet well utilized, process integration and polygeneration are promising tools which reach the double objective of increasing the efficiency of natural resources, and also minimizing the environmental impact. This paper discusses the concepts of polygeneration and energy integration and various examples of polygeneration systems: (i) sugar and energy production in a sugarcane factory; (ii) district heating and cooling with natural gas cogeneration engines and (iii) combined production of water and energy. It is clearly evident that polygeneration systems which include appropriate process integration significantly increase the efficient use of natural resources. (author)

Impact of Selenium Supplementation on Growth and Selenium Accumulation on Spinach (Spinacia oleracea L.) Plants

OpenAIRE

Azadeh SAFFARYAZDI; Mehrdad LAHOUTI; Ali GANJEALI; Hassan BAYAT

2012-01-01

Selenium (Se) has been proved to be an essential element for humans and animals. However, less is known about its effects on plants. A hydroponic experiment was carried out to investigate the effects of selenium on growth, selenium accumulation and some physiological characteristics of spinach (Spinacia oleracea L. cv. �Missouri�) plants. Plants were grown in Hoagland nutrient solution amended with sodium selenite at 0 (control), 1, 2, 4, 6 and 10 mg.L-1 for 28 days. Growth parameters like sh...

Effect of selenium supplementation on pigeon reproductive performance, selenium concentration and antioxidant status.

Science.gov (United States)

Wang, Y; Yang, H M; Cao, W; Li, Y B

2017-09-01

The effects of dietary supplementation of sodium selenite (SS) on the reproductive performance and the concentration of selenium, glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), and malondialdehyde (MDA) were determined, and expression of glutathione peroxidase 4 (GPx4) and bone morphogenic protein 15 (BMP15) was evaluated. Paired pigeons (n = 864) were fed: T1 received no SS, while T2, T3, and T4 received 0.5, 1.0, and 1.5 mg of SS/kg of dry matter (DM), respectively. Treatments were performed in triplicate with 72 pairs in each replicate. The results showed that selenium supplementation significantly affected pigeon reproductive performance. Birds fed 1.0 mg of SS/kg displayed higher egg production (P > 0.05), higher birth rate, and lower dead sperm rate than the control group (P Selenium and biochemical analyses revealed a higher selenium concentration in the 1.5 mg of SS/kg group than in the control group (P  0.05); however, in plasma, MDA was lower in the control group (P  0.05), while in ovary, BMP15 was down-regulated in the 1.5 mg of SS/kg group (P selenium concentration, and 0.5 mg of SS/kg up-regulated GSH-Px activity. © 2017 Poultry Science Association Inc.

Absorption and retention of selenium from shrimps in man

DEFF Research Database (Denmark)

Bugel, S. H.; Sandstrom, B.; Larsen, Erik Huusfeldt

2001-01-01

This study was undertaken to evaluate the bioavailability of selenium in shrimps, a possible good source of selenium, by measurements of the absorption and retention of selenium and the effects on plasma selenium concentration and glutathione peroxidase activity. Twelve healthy young subjects (9F...... of the study, after 2, 4, and 6 weeks. The selenium intake increased from 39.4 +/- 15.3 mug/d to 127 +/- 5.5 mug/d with the addition of shrimps. The apparent absorption of selenium from shrimps was 83 +/- 4%, Faecal and urinary selenium excretion was 32.5 +/- 17.0 mug/d and 21.2 +/- 9.0 mug/d, re spectively...... and the total retention of selenium was 3.1 +/- 1.1 mg. Plasma selenium concentrations were 95.2 +/- 9.7 mug/L and 101.5 +/- 9.7 mug/L before and after six weeks of shrimp intake, respectively (p...

Arsenic and selenium in microbial metabolism

Science.gov (United States)

Stolz, John F.; Basu, Partha; Santini, Joanne M.; Oremland, Ronald S.

2006-01-01

Arsenic and selenium are readily metabolized by prokaryotes, participating in a full range of metabolic functions including assimilation, methylation, detoxification, and anaerobic respiration. Arsenic speciation and mobility is affected by microbes through oxidation/reduction reactions as part of resistance and respiratory processes. A robust arsenic cycle has been demonstrated in diverse environments. Respiratory arsenate reductases, arsenic methyltransferases, and new components in arsenic resistance have been recently described. The requirement for selenium stems primarily from its incorporation into selenocysteine and its function in selenoenzymes. Selenium oxyanions can serve as an electron acceptor in anaerobic respiration, forming distinct nanoparticles of elemental selenium that may be enriched in (76)Se. The biogenesis of selenoproteins has been elucidated, and selenium methyltransferases and a respiratory selenate reductase have also been described. This review highlights recent advances in ecology, biochemistry, and molecular biology and provides a prelude to the impact of genomics studies.

Selenium Level and Dyslipidemia in Rural Elderly Chinese

Science.gov (United States)

Su, Liqin; Gao, Sujuan; Unverzagt, Frederick W.; Cheng, Yibin; Hake, Ann M.; Xin, Pengju; Chen, Chen; Liu, Jingyi; Ma, Feng; Bian, Jianchao; Li, Ping; Jin, Yinlong

2015-01-01

Objective Higher selenium level has been hypothesized to have the potential to reduce the risk of cardiovascular diseases including dyslipidemia. However, results from previous studies are inconsistent. This study aims to determine the association between selenium level and dyslipidemia in elderly Chinese with relatively low selenium status. Methods A cross-sectional study of 1859 participants aged 65 or older from four rural counties in China was conducted. Serum total cholesterol (TC), triglycerides (TG), high density lipoprotein-cholesterol (HDLC) and low-density lipoprotein-cholesterol (LDLC), nail selenium concentration and APOE genotype were measured in all subjects. The four types of dyslipidemia were defined as >5.17mmol/L for High-TC, >1.69 mmol/L for High-TG, >3.36 mmol/L for High-LDLC, and selenium levels and the risk of dyslipidemia. Results Mean nail selenium concentration was 0.465μg/gin this sample. Rates for High-TC, High-LDLC, High-TG, Low-HDLC were 18.13%, 13.23%, 12.21% and 32.76% respectively. Results from logistic models indicated that higher selenium levels were significantly associated with higher risk of High-TC, High-LDLC and lower risk of Low-HDLC adjusting for covariates (p selenium quartile group, participants in selenium quartile groups 2, 3 and 4 had significantly higher rates of High-TC, High-LDLC, High-TG, and lower rate of Low-HDLC adjusting for covariates. No significant association was observed between selenium level and the risk of High-TG. APOEε4 carriers had higher rates of High-TC and High-LDLC. There was no interaction between selenium level and APOE with the rates of dyslipidemia. Conclusions Our results suggest long-term selenium exposure level may be associated with the risk of dyslipidemia in elderly population. Future studies are needed to examine the underlying mechanism of the association. PMID:26380972

TECHNICAL EFFICIENCY OF AGRICULTURAL RESOURCES USE IN RUSSIA

Directory of Open Access Journals (Sweden)

V. M. Korotchenya

2016-01-01

Full Text Available Technical efficiency of agricultural resources use in Russia is assessed. As methodology for calculations the author used Data envelopment analysis (DEA which is the nonparametric method based on linear programming. The essence of the DEA method consists in an efficiency evaluation of homogeneous units of decision making proceeding from creation on the basis of real data (amounts of resources and amounts of types of output of general border of production capabilities. CCR-I model was offerd as a specific kind of the DEA model. It is the radial DEA model with continual returns to scale and orientation to resources. The group of 54 countries included in a research consisted of the states of the CIS, BRIC, the EU, OECD. The time frames of calculation were established: 1992-2007 and 2008-2012 (owing to lack of uniform data for all time interval. Аmount of agricultural products was used as output. Agricultural lands, an economically active population in agriculture, farm machines and the equipment, a livestock, fertilizers were used in the form of resources. The main source of statistical data is FAOSTAT. From 54 countries under consideration Belgium, Greece, Israel, Malta and the Netherlands became leaders in technical efficiency of agricultural industry in 1992-2007. Inefficient use of agricultural resources, especially lands was established as a result of the conducted research in Russia. On average efficiency of use of agricultural lands in our country can be increased by 8 times, work - by 2-2.5 times, machines - by 2-3 times, a livestock and fertilizers - by 1.5-2 times. Good tendencies to growth of efficiency of agricultural production are notice in 2008-2012.

Selenium in human milk: An Australian study

International Nuclear Information System (INIS)

Cumming, F.J.; Fardy, J.J.; Woodward, D.R.

1991-01-01

The aims of this Australian study were to determine (total) selenium concentration in breast milk and in maternal blood, and to assess the relationship between the two. The authors also aimed to assess the infants' selenium intake. Twenty lactating women from Brisbane (Queensland) participated in the study, at 6-12 weeks post-partum. Small samples (approximately 10 ml) of breast-milk were manually expressed at the beginning and end of a mid-morning feed, from the first breast offered at that feed. Venous blood samples (10 ml) were also collected from the mothers. Milk and blood samples were analyzed by neutron activation analysis. Babies' milk intake over a 24-hour period was estimated using a modified test-weighing technique. Infant selenium intakes were calculated directly for each infant, using his/her mother's milk selenium level and his/her own 24-hour breast milk intake. The mean selenium concentration in maternal blood was 101 (±SD 19) ng/g and in maternal serum 81 (±15) ng/g. Breast milk selenium concentrations (11.9 ± 3.5 ng/g) were fairly low by international standards. There was no correlation between selenium concentrations in milk and blood (or serum). The infants' 24-hour breast-milk intakes were 856 ± 172 g, and their selenium intakes were 10.7 ± 4.1 μg per day

Is selenium supplementation in autoimmune thyroid diseases justified?

DEFF Research Database (Denmark)

Winther, Kristian H.; Bonnema, Steen; Hegedüs, Laszlo

2017-01-01

PURPOSE OF REVIEW: This review provides an appraisal of recent evidence for or against selenium supplementation in patients with autoimmune thyroid diseases, and discusses possible effect mechanisms. RECENT FINDINGS: Epidemiological data suggest an increased prevalence of autoimmune thyroid...... diseases under conditions of low dietary selenium intake. Two systematic reviews have evaluated controlled trials among patients with autoimmune thyroiditis and report that selenium supplementation decreases circulating thyroid autoantibodies. The immunomodulatory effects of selenium might involve reducing...... proinflammatory cytokine release. However, clinically relevant effects of selenium supplementation, including improvement in quality of life, are more elusive. In Graves’ disease, some, but not all, trials indicate that adjuvant selenium supplementation enhances the restoration of biochemical euthyroidism...

Determination of total selenium and selenium distribution in the milk phases in commercial cow's milk by HG-AAS

Energy Technology Data Exchange (ETDEWEB)

Muniz-Naveiro, Oscar; Dominguez-Gonzalez, Raquel; Bermejo-Barrera, Adela; Bermejo-Barrera, Pilar [University of Santiago de Compostela, Department of Analytical Chemistry, Nutrition and Bromatology, Santiago de Compostela (Spain); Cocho, Jose A. [University Clinical Hospital, Laboratory of Metabolic and Nutritional Disorders, Santiago de Compostela (Spain); Fraga, Jose M. [University Clinical Hospital, Department of Pediatrics, Santiago de Compostela (Spain)

2005-03-01

A procedure has been developed for determining the selenium in cow's milk using hydride generation-atomic absorption spectrometry (HG-AAS) following microwave-assisted acid digestion. The selenium distributions in milk whey, fat and micellar casein phases were studied after separating the different phases by ultracentrifugation and determining the selenium in all of them. The detection limits obtained by HG-AAS for the whole milk, milk whey and micellar casein were 0.074, 0.065 and 0.075 {mu}g l{sup -1}, respectively. The accuracy for the whole milk was checked by using a Certified Reference Material CRM 8435 whole milk powder from NIST, and the analytical recoveries for the milk whey and casein micelles were 100.9 and 96.9%, respectively. A mass balance study of the determination of selenium in the different milk phases was carried out, obtaining values of 95.5-100.8%. The total content of selenium was determined in 37 milk samples from 15 different manufacturers, 19 whole milk samples and 18 skimmed milk samples. The selenium levels found were within the 8.5-21 {mu}g l{sup -1} range. The selenium distributions in the different milk phases were studied in 14 whole milk samples, and the highest selenium levels were found in milk whey (47.2-73.6%), while the lowest level was found for the fat phase (4.8-16.2%). A strong correlation was found between the selenium levels in whole milk and the selenium levels in the milk components. (orig.)

Efficient Resource Utilization in Shared-Everything Environments

NARCIS (Netherlands)

S. Manegold (Stefan); J.K. Obermaier

1998-01-01

textabstractEfficient resource usage is a key to achieve better performance in parallel database systems. Up to now, most research has focussed on balancing the load on several resources of the same type, i.e. balancing either CPU load or I/O load. In this paper, we present floating probe, a

Determinants of selenium in the toenail biomonitor

International Nuclear Information System (INIS)

Morris, J.S.; Spate, V.L.; Ngwenyama, R.A.

2006-01-01

The evaluation of human nails as a measure of selenium intake and to assess selenium status in critical tissues is now being used routinely to investigate hypotheses relating selenium status to chronic disease, especially cancer. In this study we report on our observations of the major determinants of toenail selenium concentrations. Toenail specimens (3575) were, under a protocol we provided, self-collected by adult females (1940, 54.3%) and males (1635, 45.7%) living in 111 of Missouri's 114 counties. The health-conscious participants ranged in age from 18 to 94 years with means of 53.7±14.1 and 56.4±14.2 years for females and males, respectively. Selenium supplement use was over represented, 39.1% and 42.7%, and smoking was under represented, 7.5% and 7.8%, for females and males, respectively. The major determinants of toenail selenium concentration were supplement use, sex and cigarette smoking. We found no overall correlations with age, body mass index or diet selection. (author)

Selenium balance in the adult cat in relation to intake of dietary sodium selenite and organically bound selenium

NARCIS (Netherlands)

Todd, S.E.; Thomas, D.G.; Hendriks, W.H.

2012-01-01

The response of cats to dietary sodium selenite (Na2SeO3) and organically bound selenium was studied in two separate studies with four cats per treatment and three levels of selenium supplementation (targets 1.0, 1.5 and 2.0 µg/g DM) for each Se source. Whole blood and plasma selenium concentrations

Loss of Selenium-Binding Protein 1 Decreases Sensitivity to Clastogens and Intracellular Selenium Content in HeLa Cells.

Science.gov (United States)

Zhao, Changhui; Zeng, Huawei; Wu, Ryan T Y; Cheng, Wen-Hsing

2016-01-01

Selenium-binding protein 1 (SBP1) is not a selenoprotein but structurally binds selenium. Loss of SBP1 during carcinogenesis usually predicts poor prognosis. Because genome instability is a hallmark of cancer, we hypothesize that SBP1 sequesters cellular selenium and sensitizes cancer cells to DNA-damaging agents. To test this hypothesis, we knocked down SBP1 expression in HeLa cervical cancer cells by employing a short hairpin RNA (shRNA) approach. Reduced sensitivity to hydrogen peroxide, paraquat and camptothecin, reactive oxygen species content, and intracellular retention of selenium after selenomethionine treatment were observed in SBP1 shRNA HeLa cells. Results from Western analyses showed that treatment of HeLa cells with selenomethionine resulted in increased SBP1 protein expression in a dose-dependent manner. Knockdown of SBP1 rendered HeLa cells increased expression of glutathione peroxidase-1 but not glutathione peroxidase-4 protein levels and accelerated migration from a wound. Altogether, SBP1 retains supplemental selenium and sensitizes HeLa cancer cells to clastogens, suggesting a new cancer treatment strategy by sequestering selenium through SBP1.

Pre-Antiretroviral Therapy Serum Selenium Concentrations Predict WHO Stages 3, 4 or Death but not Virologic Failure Post-Antiretroviral Therapy

Directory of Open Access Journals (Sweden)

Rupak Shivakoti

2014-11-01

Full Text Available A case-cohort study, within a multi-country trial of antiretroviral therapy (ART efficacy (Prospective Evaluation of Antiretrovirals in Resource Limited Settings (PEARLS, was conducted to determine if pre-ART serum selenium deficiency is independently associated with human immunodeficiency virus (HIV disease progression after ART initiation. Cases were HIV-1 infected adults with either clinical failure (incident World Health Organization (WHO stage 3, 4 or death by 96 weeks or virologic failure by 24 months. Risk factors for serum selenium deficiency (<85 μg/L pre-ART and its association with outcomes were examined. Median serum selenium concentration was 82.04 μg/L (Interquartile range (IQR: 57.28–99.89 and serum selenium deficiency was 53%, varying widely by country from 0% to 100%. In multivariable models, risk factors for serum selenium deficiency were country, previous tuberculosis, anemia, and elevated C-reactive protein. Serum selenium deficiency was not associated with either clinical failure or virologic failure in multivariable models. However, relative to people in the third quartile (74.86–95.10 μg/L of serum selenium, we observed increased hazards (adjusted hazards ratio (HR: 3.50; 95% confidence intervals (CI: 1.30–9.42 of clinical failure but not virologic failure for people in the highest quartile. If future studies confirm this relationship of high serum selenium with increased clinical failure, a cautious approach to selenium supplementation might be needed, especially in HIV-infected populations with sufficient or unknown levels of selenium.

Efficient resource utilization in shared-everything environments

NARCIS (Netherlands)

S. Manegold (Stefan); J.K. Obermaier

1997-01-01

textabstractEfficient resource usage is a key to achieve better performance in parallel database systems. Up to now, most research has focussed on balancing the load on several resources of the same type, i.e. balancing either CPU load or I/O load. In this paper, we present emph{floating probe, a

[The role of selenium in endocrine system diseases].

Science.gov (United States)

Balázs, Csaba; Rácz, Károly

2013-10-13

Oxygen derived free radicals, generated by a number of cellular reactions, include superoxide anion, hydrogen peroxide and hydroxyl radicals. They exert their cytotoxic effects mainly via peroxidation of the cell membrane resulting in the loss of membrane integrity. The essential trace element, selenium exerts complex effects on the endocrine systems, partly due to its antioxidant capacity. Well-characterized selenoproteins include iodothyronine deiodinases, glutathione peroxidases and thioredoxin reductases involved in thyroid hormone metabolism and protection from oxidative damage. The value of selenium supplementation in autoimmune thyroid disorders has been investigated and most studies confirmed the beneficial effect of selenium supplementation in Hashimoto's and Graves's diseases. Recently, selenium proved to be effective in mild inflammatory orbitopathy. There are a number of reports about the effect of selenium in diabetes mellitus, but the data are controversial as both insulin-like and diabetes-inducing effects of selenium have been described. Selenium was successfully used in both female and male infertility of autoimmune origin.

Effects of selenium supplementation on four agricultural crops.

Science.gov (United States)

Carvalho, Kathleen M; Gallardo-Williams, Maria T; Benson, Robert F; Martin, Dean F

2003-01-29

Agricultural crops can be used either to remediate selenium-contaminated soils or to increase the daily selenium intake of consumers after soil supplementation using inorganic or organic selenium sources. In this study, four agricultural crops were examined for potential selenium enhancement. Soils containing tomato, strawberry, radish, and lettuce plants were supplemented with either an inorganic or an organic form of selenium. Two different soils, i.e., low Se and high Se containing, were also used. Statistically significant differences in appearance, fruit production, and fresh weights of the fruit produced were studied. Next, the amount of selenium retained in the edible fruits, nonedible plant, and soil for each was analyzed by acid digestion followed by hydride generation atomic absorption analysis. Finally, inhibition effects on the seeds of the agricultural plants were studied. The results show that supplementation with an inorganic form of selenium led to higher retention in the plants, with a maximum of 97.5% retained in the edible portion of lettuce plants.

Resource allocation for phantom cellular networks: Energy efficiency vs spectral efficiency

KAUST Repository

Abdelhady, Amr Mohamed Abdelaziz; Amin, Osama; Alouini, Mohamed-Slim

2016-01-01

Multi-tier heterogeneous networks have become an essential constituent for next generation cellular networks. Mean-while, energy efficiency (EE) has been considered a critical design criterion along with the traditional spectral efficiency (SE) metric. In this context, we study power and spectrum allocation for the recently proposed two-tier network architecture known as phantom cellular networks. The optimization framework includes both EE and SE, where we propose an algorithm that finds the SE and EE resource allocation strategies for phantom cellular networks. Then, we compare the performance of both design strategies versus the number of users, and phantom cells share of the total number of available resource blocks. We aim to investigate the effect of some system parameters to achieve improved SE performance at a non-significant loss in EE performance, or vice versa. It was found that increasing phantom cells share of resource blocks decreases the SE performance loss due to EE optimization when compared with the optimized SE performance. © 2016 IEEE.

Resource allocation for phantom cellular networks: Energy efficiency vs spectral efficiency

KAUST Repository

Abdelhady, Amr M.

2016-07-26

Multi-tier heterogeneous networks have become an essential constituent for next generation cellular networks. Mean-while, energy efficiency (EE) has been considered a critical design criterion along with the traditional spectral efficiency (SE) metric. In this context, we study power and spectrum allocation for the recently proposed two-tier network architecture known as phantom cellular networks. The optimization framework includes both EE and SE, where we propose an algorithm that finds the SE and EE resource allocation strategies for phantom cellular networks. Then, we compare the performance of both design strategies versus the number of users, and phantom cells share of the total number of available resource blocks. We aim to investigate the effect of some system parameters to achieve improved SE performance at a non-significant loss in EE performance, or vice versa. It was found that increasing phantom cells share of resource blocks decreases the SE performance loss due to EE optimization when compared with the optimized SE performance. © 2016 IEEE.

Selenium and phosphorus interaction in pea (pisum sativum L.)

International Nuclear Information System (INIS)

Singh, Mahendra; Bhandari, D.K.

1975-01-01

The interaction of selenium and phosphorus on the dry matter yield and concentration and uptake of phosphorus, sulfur and selenium was studied in pea (Pisum sativnum) var. T 163. The fertilizer was tagged with P 32 . It was observed that increased concentration of applied selenium in soil decreased the dry matter yield and increased the concentration and uptake of total P, soil P and selenium in pea plants. Increased concentration of P alone increased dry matter yield, concentration and uptake of total, soil and fertilizer P and selenium which was beyond safe limits, and decreased concentration and uptake of sulphur. Selenium and phosphorus showed strong synergetic relationship by increasing the concentration of each other in plants while both showed antagonistic effect on the concentration of sulphur. Phosphorus compensated the toxic effect of selenium and improved the growth and dry matter yield of pea plants. The highest selenium concentration of 22.4 ppm was observed in 100 ppm phosphorus with 5 ppm selenium treated pots while lowest (0.10 ppm) in control. (author)

Does mercury vapor exposure increase urinary selenium excretion

Energy Technology Data Exchange (ETDEWEB)

Hongo, T; Suzuki, T; Himeno, S; Watanabe, C; Satoh, H; Shimada, Y

1985-01-01

It has been reported that an increase of urinary selenium excretion may occur as a result of mercury vapor exposure. However, experimental data regarding the interaction between mercury vapor and selenium have yielded ambiguous results about the retention and elimination of selenium due to mercury vapor exposure and the decrease of selenium excretion due to mercury in the form of mercuric mercury (Hg/sup 2 +/). In this study, the authors measured urinary mercury and selenium in workers with or without exposure to mercury vapor to determine whether or not urinary selenium excretion was increased as a result of mercury vapor exposure. Urine samples were collected from 141 workers, 71 men and 70 women, whose extent of exposure to mercury vapor varied according to their job sites. Workers were divided into five groups according to their urinary mercury levels. The mercury level in group I was less than 2.8 nmol/mmol creatinine which means that this group was mostly free from mercury exposure. The average age was almost identical among the groups. For both sexes, group V (with the highest urinary mercury level) had the lowest urinary selenium level, but one-way variance analysis (ANOVA) did not reveal any significant variations of urinary selenium with urinary mercury levels; however, a weak but significant negative correlation between mercury and selenium was found in men.

Mercury and selenium levels, and selenium:mercury molar ratios of brain, muscle and other tissues in bluefish (Pomatomus saltatrix) from New Jersey, USA

Science.gov (United States)

Burger, Joanna; Jeitner, Christian; Donio, Mark; Pittfield, Taryn; Gochfeld, Michael

2015-01-01

A number of contaminants affect fish health, including mercury and selenium, and the selenium: mercury molar ratio. Recently the protective effects of selenium on methylmercury toxicity have been publicized, particularly for consumption of saltwater fish. Yet the relative ameliorating effects of selenium on toxicity within fish have not been examined, nor has the molar ratio in different tissues, (i.e. brain). We examined mercury and selenium levels in brain, kidney, liver, red and white muscle, and skin and scales in bluefish (Pomatomus saltatrix) from New Jersey to determine whether there were toxic levels of either metal, and we computed the selenium: mercury molar ratios by tissues. Total mercury averaged 0.32 ± 0.02 ppm wet weight in edible muscle and 0.09 ± 0.01 ppm in brain. Selenium concentration averaged 0.37 ± 0.03 in muscle and 0.36 ± 0.03 ppm in brain. There were significant differences in levels of mercury, selenium, and selenium: mercury molar ratios, among tissues. Mercury and selenium levels were correlated in kidney and skin/scales. Mercury levels were highest in kidney, intermediate in muscle and liver, and lowest in brain and skin/scales; selenium levels were also highest in kidney, intermediate in liver, and were an order of magnitude lower in the white muscle and brain. Mercury levels in muscle, kidney and skin/scales were positively correlated with fish size (length). Selenium levels in muscle, kidney and liver were positively correlated with fish length, but in brain; selenium levels were negatively correlated with fish length. The selenium: mercury molar ratio was negatively correlated with fish length for white muscle, liver, kidney, and brain, particularly for fish over 50 cm in length, suggesting that older fish experience less protective advantages of selenium against mercury toxicity than smaller fish, and that consumers of bluefish similarly receive less advantage from eating larger fish. PMID:23202378

Combination of Lewis Basic Selenium Catalysis and Redox Selenium Chemistry: Synthesis of Trifluoromethylthiolated Tertiary Alcohols with Alkenes.

Science.gov (United States)

Zhu, Zechen; Luo, Jie; Zhao, Xiaodan

2017-09-15

A new and efficient method for diaryl selenide catalyzed vicinal CF 3 S hydroxylation of 1,1-multisubstitued alkenes has been developed. Various trifluoromethylthiolated tertiary alcohols could be readily synthesized under mild conditions. This method is also effective for the intramolecular cyclization of alkenes tethered by carboxylic acid, hydroxy, sulfamide, or ester groups and is associated with the introduction of a CF 3 S group. Mechanistic studies have revealed that the pathway involves a redox cycle between Se(II) and Se(IV) and Lewis basic selenium catalysis.

Selenium nanoparticles: potential in cancer gene and drug delivery.

Science.gov (United States)

Maiyo, Fiona; Singh, Moganavelli

2017-05-01

In recent decades, colloidal selenium nanoparticles have emerged as exceptional selenium species with reported chemopreventative and therapeutic properties. This has sparked widespread interest in their use as a carrier of therapeutic agents with results displaying synergistic effects of selenium with its therapeutic cargo and improved anticancer activity. Functionalization remains a critical step in selenium nanoparticles' development for application in gene or drug delivery. In this review, we highlight recent developments in the synthesis and functionalization strategies of selenium nanoparticles used in cancer drug and gene delivery systems. We also provide an update of recent preclinical studies utilizing selenium nanoparticles in cancer therapeutics.

Preliminary Study on the Standard of Selenium Content in Agricultural Products

Institute of Scientific and Technical Information of China (English)

ZHANG Zhi-yuan; YOU Yong; GUO Qing-quan; WANG Yong-hong; DENG Shi-lin

2012-01-01

With the improvement of living standards, people pay more attention to the agricultural products with health protection function, and the selenium-rich agricultural products attract more and more consumers. The main biological role of selenium is to resist oxidation and inflammatory response, mainly focusing on resisting aging, preventing cardiovascular disease, protecting eyesight, counteracting or destroying the toxic properties, preventing cancer and thyroid disease. In most areas of China, there is a widespread shortage of selenium, thus producing selenium-rich agricultural products to provide natural selenium-rich health food to the areas in need of selenium, has gradually become a new hot spot of China’s health food industry, but high content of selenium in food is detrimental to human body, even leads to selenium intoxication, and artificially adding inorganic selenium is difficult to guarantee that the selenium content of agricultural products is not exceeded. According to human body’s daily demand for selenium in dietetics and the content of selenium in agricultural products in the Chinese food composition table, we put forward the recommendations on the standard of selenium in agricultural products, in order to provide the basis for China to formulate the health standard of selenium content in selenium-rich agricultural products.

Selenium deficiency and the effects of supplementation on preterm infants

Directory of Open Access Journals (Sweden)

Renata Germano B. O. N. Freitas

2014-03-01

Full Text Available Objective: This study aimed to review the literature about blood concentrations of selenium associated with gestational age, feeding, supplementation and related clinical features in preterm infants. Data sources: Systematic review in the following databases: MEDLINE, PubMed, Google academics, SciELO. org, ScienceDirect (Elsevier and CINAHL-Plus with Full Text (EBSCO. Articles published up to January 2013 with the keywords "selenium deficiency", "selenium supplementation", "neonates", "infants", "newborn" and "preterm infants" were selected. Data synthesis: The studies reported that low blood selenium levels are associated with increased risk of respiratory diseases. Preterm infants, especially with low birth weight, presented lower selenium levels. Selenium deficiency has also been associated with the use of oral infant formula, enteral and parenteral nutrition (with or without selenium addition. The optimal dose and length of selenium supplementation is not well-established, since they are based only on age group and selenium ingestion by breastfed children. Furthermore, the clinical status of the infant affected by conditions that may increase oxidative stress, and consequently, selenium requirements is not taken into account. Conclusions: Prematurity and low birth weight can contribute to low blood selenium in premature infants. Selenium supplementation seems to minimize or prevent clinical complications caused by prematurity.

Job Scheduling with Efficient Resource Monitoring in Cloud Datacenter

Directory of Open Access Journals (Sweden)

Shyamala Loganathan

2015-01-01

Full Text Available Cloud computing is an on-demand computing model, which uses virtualization technology to provide cloud resources to users in the form of virtual machines through internet. Being an adaptable technology, cloud computing is an excellent alternative for organizations for forming their own private cloud. Since the resources are limited in these private clouds maximizing the utilization of resources and giving the guaranteed service for the user are the ultimate goal. For that, efficient scheduling is needed. This research reports on an efficient data structure for resource management and resource scheduling technique in a private cloud environment and discusses a cloud model. The proposed scheduling algorithm considers the types of jobs and the resource availability in its scheduling decision. Finally, we conducted simulations using CloudSim and compared our algorithm with other existing methods, like V-MCT and priority scheduling algorithms.

Selenium accumulation in lettuce germplasm

Science.gov (United States)

Selenium (Se) is an essential micronutrient for animals and humans. Increasing Se content in food crops offers an effective approach to reduce the widespread selenium deficiency problem in many parts of the world. In this study, we evaluated thirty diverse accessions of lettuce (Lactuca sativa L.) f...

SELENIUM ACCUMULATION BY BASIL PLANTS (OCINUM BASILICUM L.

Directory of Open Access Journals (Sweden)

N. A. Golubkina

2014-01-01

Full Text Available Selenium accumulation level in basil plants is investigated. A direct correlation between selenium concentration and essential oil content is demonstrated for basil and other aroma plants. No correlation is found between selenium and flavonoids.

A Study of Selenium in Leprosy

Directory of Open Access Journals (Sweden)

Donna Partogi

2018-03-01

CONCLUSIONS: Selenium serum levels of patients with PB leprosy are higher than patients with MB leprosy, and high bacteriological index in patients with leprosy were correlated with low selenium serum levels.

Selenium's importance in regulatory issues regarding mercury

Energy Technology Data Exchange (ETDEWEB)

Raymond, Laura J.; Ralston, Nicholas V.C. [University of North Dakota Energy and Environmental Research Center, 15 North 23rd Street, Stop 9018, Grand Forks, ND 58202-9018 (United States)

2009-11-15

Current seafood safety and health risk assessment criteria use mercury concentrations as their sole basis. This unfortunate limitation omits consideration of selenium, an essential trace element that appears to be the primary molecular target of mercury toxicity. Although selenium has been recognized for decades as a means of counteracting mercury toxicity, its effects have often been overlooked or misunderstood. Experimental animal studies have demonstrated that increasing concentrations of selenium throughout the normal dietary range increasingly counteracts methylmercury toxicity. Dietary concentrations of selenium that are slightly less than the average amount present in ocean fish have been shown to completely prevent the onset of toxic symptoms of mercury toxicity, while animals fed lesser amounts of selenium rapidly sickened and died. Dietary selenium from a variety of sources including ocean fish such as tuna, swordfish, menhaden, and rockfish has been shown to counteract mercury toxicity. Since ocean fish are among the richest sources of dietary selenium, it is important to include selenium concentration measurements in future mercury risk assessments and seafood safety criteria. Mercury:selenium molar ratios in blood provide far more consistent and physiologically meaningful risk assessments. Comprehensive seafood safety criteria such as the Selenium Health Benefit Value enable clear differentiation between seafoods that are safe and those that are hazardous for human consumption. Use of parameters that integrate mercury-selenium relationships also make it easy to understand the differences between the findings of maternal mercury exposure studies that have been performed in New Zealand, the Faroes, the Seychelles, and the United Kingdom. Development of criteria for evaluating mercury-selenium interactions will enhance environmental protection and improve public safety. (author)

Automated method for the determination of total arsenic and selenium in natural and drinking water by HG-AAS.

Science.gov (United States)

Pistón, Mariela; Silva, Javier; Pérez-Zambra, Ramiro; Dol, Isabel; Knochen, Moisés

2012-04-01

A multicommutated flow system was designed and evaluated for the determination of total arsenic and selenium by Hydride Generation Atomic Absorption Spectrometry (HG-AAS). It was applied to the determination of arsenic and selenium in samples of natural and drinking water. Detection limits were 0.46 and 0.08 μg l(-1) for arsenic and selenium, respectively; sampling frequency was 120 samples h(-1) for arsenic and 160 samples h(-1) for selenium. Linear ranges found were 1.54-10 μg l(-1) (R = 0.999) for arsenic and 0.27-27 μg l(-1) (R = 0.999) for selenium. Accuracy was evaluated by spiking various water samples and using a reference material. Recoveries were in the range 95-116%. Analytical precision (s ( r ) (%), n = 10) was 6% for both elements. Compared with the Standard Methods, APHA, 3114B manual method, the system consumes at least 10 times less sample per determination, and the quantities of acid and reducing agent used are significantly lower with a reduction in the generation of pollutants and waste. As an additional advantage, the system is very fast, efficient and environmentally friendly for monitoring total arsenic and selenium levels in waters.

Extracellular Polymeric Substances Govern the Surface Charge of Biogenic Elemental Selenium Nanoparticles

KAUST Repository

Jain, Rohan

2015-02-03

© 2014 American Chemical Society. The origin of the organic layer covering colloidal biogenic elemental selenium nanoparticles (BioSeNPs) is not known, particularly in the case when they are synthesized by complex microbial communities. This study investigated the presence of extracellular polymeric substances (EPS) on BioSeNPs. The role of EPS in capping the extracellularly available BioSeNPs was also examined. Fourier transform infrared (FT-IR) spectroscopy and colorimetric measurements confirmed the presence of functional groups characteristic of proteins and carbohydrates on the BioSeNPs, suggesting the presence of EPS. Chemical synthesis of elemental selenium nanoparticles in the presence of EPS, extracted from selenite fed anaerobic granular sludge, yielded stable colloidal spherical selenium nanoparticles. Furthermore, extracted EPS, BioSeNPs, and chemically synthesized EPS-capped selenium nanoparticles had similar surface properties, as shown by ζ-potential versus pH profiles and isoelectric point measurements. This study shows that the EPS of anaerobic granular sludge form the organic layer present on the BioSeNPs synthesized by these granules. The EPS also govern the surface charge of these BioSeNPs, thereby contributing to their colloidal properties, hence affecting their fate in the environment and the efficiency of bioremediation technologies.

[Pharmaconutrition with parenteral selenium in sepsis].

Science.gov (United States)

Langlois, P L; de Oliveira Figliolino, L F; Hardy, G; Manzanares, W

2014-04-01

Critical illness is characterized by oxidative stress which leads to multiple organ failure, and sepsis-related organ dysfunction remains the most common cause of death in the intensive care unit. Over the last 2 decades, different antioxidant therapies have been developed to improve outcomes in septic patients. According to recent evidence, selenium therapy should be considered the cornerstone of the antioxidant strategies. Selenium given as selenious acid or sodium selenite should be considered as a drug or pharmaconutrient with prooxidant and cytotoxic effects when a loading dose in intravenous bolus form is administered, particularly in the early stage of severe sepsis/septic shock. To date, several phase ii trials have demonstrated that selenium therapy may be able to decrease mortality, improve organ dysfunction and reduce infections in critically ill septic patients. The effect of selenium therapy in sepsis syndrome must be confirmed by large, well designed phase iii clinical trials. The purpose of this review is to discuss current evidence on selenium pharmaconutrition in sepsis syndrome. Copyright © 2013 Elsevier España, S.L. and SEMICYUC. All rights reserved.

Effect of long-term selenium supplementation on mortality

DEFF Research Database (Denmark)

Rayman, Margaret P.; Winther, Kristian Hillert; Pastor-Barriuso, Roberto

2018-01-01

Background: Selenium, an essential trace element, is incorporated into selenoproteins with a wide range of health effects. Selenoproteins may reach repletion at a plasma selenium concentration of ∼ 125 μg/L, at which point the concentration of selenoprotein P reaches a plateau; whether sustained...... concentrations higher than this are beneficial, or indeed detrimental, is unknown. Objective: In a population of relatively low selenium status, we aimed to determine the effect on mortality of long-term selenium supplementation at different dose levels. Design: The Denmark PRECISE study was a single...... for extension of the study and mortality assessment. Participants were randomly assigned to treatment with 100, 200, or 300 μg selenium/d as selenium-enriched-yeast or placebo-yeast for 5 years from randomization in 1998-1999 and were followed up for mortality for a further 10 years (through March 31, 2015...

Biogeochemical studies of selenium in the Indian Ocean

International Nuclear Information System (INIS)

Hattori, H.; Nakaguchi, Y.; Hiraki, K.; Kimura, M.; Koike, Y.

1999-01-01

Selenium that is a one of trace essential elements exists mainly in the chemical form of Se(IV), Se(VI) and organic selenium in ocean. Moreover, the monitoring of the selenium species has become a matter of interest as a mean of estimating their influence in biological processes in ocean. In recent works, some investigators reported that Se(IV) shows nutrient-type especially like silica's behavior, Se(VI) shows an approximately constant value, and the biological activities control the distribution of organic selenium. However, these reports were not included the whole world's oceans. It is necessary to research several oceans for the explication of fate on selenium. We investigated at the most interesting area - the Eastern Indian Ocean where should play a key role in global ocean's cycle for acquiring the new knowledge of selenium species at first

Production of selenium-enriched milk and dairy products

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Csapó J.

2015-01-01

Full Text Available Until the middle of the last century, selenium was considered to be toxic, but recently it turned out to be a micronutrient with important physiological effects, whose lack impedes the functioning of several enzymes, while in the case of a prolonged deficiency, disease processes can also occur in the body. Hungary belongs to the selenium-deficient regions in Europe; therefore, our aim was to contribute to the improvement of selenium supply of the population through increasing the selenium content of milk and dairy products. A daily supplementation of 1-6 mg organic selenium to the feed of dairy cows increases the selenium content of milk from the value of 18 μg/kg to 94 μg/kg in 8 weeks, decreasing again to the initial value in 6 weeks after stopping the supplementation.

In vivo and in vitro testing for selenium and selenium compounds bioavailability assessment in foodstuff.

Science.gov (United States)

Moreda-Piñeiro, Jorge; Moreda-Piñeiro, Antonio; Bermejo-Barrera, Pilar

2017-03-04

The assessment of selenium and selenium species bioavailability in foodstuff is of special concern on the context of human nutrition. In vivo (human and animal), and in vitro tests are important approaches for estimating the bioavailability of toxic and essential compounds to humans. An overview on in vivo and in vitro bioavailability assays for releasing selenium and selenium species in foodstuffs is summarized. Se and Se species content in a foodstuff critically influence Se bioavailability and bioactivity to humans and animals. Se bioavailability is affected by foodstuff-matrix major composition and minor components. Foodstuffs processing and/or treatments could enhancement or decrease Se bioavailability. Experimental conditions such as the selection of healthy status of examined people (in in vivo humans approaches), the selection of animal model (in vivo animals approaches), or the selection of GI conditions (in in vitro tests) could determines the results. Thus, international standardized protocol for in vivo and in vitro approaches assessment is mandatory.

Selenium and Selenoprotein Deficiencies Induce Widespread Pyogranuloma Formation in Mice, while High Levels of Dietary Selenium Decrease Liver Tumor Size Driven by TGFα

Science.gov (United States)

Zhong, Nianxin; Ward, Jerrold M.; Perella, Christine M.; Hoffmann, Victoria J.; Rogers, Keith; Combs, Gerald F.; Schweizer, Ulrich; Merlino, Glenn; Gladyshev, Vadim N.; Hatfield, Dolph L.

2013-01-01

Changes in dietary selenium and selenoprotein status may influence both anti- and pro-cancer pathways, making the outcome of interventions different from one study to another. To characterize such outcomes in a defined setting, we undertook a controlled hepatocarcinogenesis study involving varying levels of dietary selenium and altered selenoprotein status using mice carrying a mutant (A37G) selenocysteine tRNA transgene (TrsptG37) and/or a cancer driver TGFα transgene. The use of TrsptG37 altered selenoprotein expression in a selenoprotein and tissue specific manner and, at sufficient dietary selenium levels, separate the effect of diet and selenoprotein status. Mice were maintained on diets deficient in selenium (0.02 ppm selenium) or supplemented with 0.1, 0.4 or 2.25 ppm selenium or 30 ppm triphenylselenonium chloride (TPSC), a non-metabolized selenium compound. TrsptG37 transgenic and TGFα/TrsptG37 bi-transgenic mice subjected to selenium-deficient or TPSC diets developed a neurological phenotype associated with early morbidity and mortality prior to hepatocarcinoma development. Pathology analyses revealed widespread disseminated pyogranulomatous inflammation. Pyogranulomas occurred in liver, lungs, heart, spleen, small and large intestine, and mesenteric lymph nodes in these transgenic and bi-transgenic mice. The incidence of liver tumors was significantly increased in mice carrying the TGFα transgene, while dietary selenium and selenoprotein status did not affect tumor number and multiplicity. However, adenoma and carcinoma size and area were smaller in TGFα transgenic mice that were fed 0.4 and 2.25 versus 0.1 ppm of selenium. Thus, selenium and selenoprotein deficiencies led to widespread pyogranuloma formation, while high selenium levels inhibited the size of TGFα–induced liver tumors. PMID:23460847

In Situ Immobilization of Selenium in Sediment

Energy Technology Data Exchange (ETDEWEB)

Moore, Robert C. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Stewart, Thomas Austin [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2014-09-01

This project focused on the use of a sorbent, carbonated apatite, to immobilize selenium in the environment. It is know that apatite will sorb selenium and based on the mechanism of sorption it is theorized that carbonated apatite will be more effective that pure apatite. Immobilization of selenium in the environment is through the use of a sorbent in a permeable reactive barrier (PRB). A PRB can be constructed by trenching and backfill with the sorbent or in the case of apatite as the sorbent formed in situ using the apatite forming solution of Moore (2003, 2004). There is very little data on selenium sorption by carbonated apatite in the literature. Therefore, in this work, the basic sorptive properties of carbonated apatite were investigated. Carbonated apatite was synthesized by a precipitation method and characterized. Batch selenium kinetic and equilibrium experiments were performed. The results indicate the carbonated apatite contained 9.4% carbonate and uptake of selenium as selenite was rapid; 5 hours for complete uptake of selenium vs. more than 100 hours for pure hydroxyapatite reported in the literature. Additionally, the carbonated apatite exhibited significantly higher distribution coefficients in equilibrium experiments than pure apatite under similar experimental conditions. The next phase of this work will be to seek additional funds to continue the research with the goal of eventually demonstrating the technology in a field application.

Selenium: its potential role in male infertility

International Nuclear Information System (INIS)

Oguntibeju, O.O.; Esterhuyse, J.S.; Truter, E.J.

2009-01-01

Currently, biomedical research is showing interest in the anti-oxidant activity of selenium. This could be due to compelling evidence that reported that oxidative damage to cells and cell membranes is one of the causative agents in the pathogenesis of many disease states including male infertility. Selenium is a trace element which may be found in soil, water and some foods and is considered to be an essential element which plays an active role in several metabolic pathways and is believed to perform several important roles in the human body. These roles include anti-oxidative activities at cellular level and participating in different enzyme systems. Selenium also serves as a vital component in the maintenance of muscle cell and red blood cell integrity, playing a role in the synthesis of deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). It has also been reported that selenium is essential in the detoxification of toxic metals in the human system, foetal respiration and energy transfer reactions as well as in the production of sperm cells. It is thought that male infertility can be the result of a selenium deficiency as the absence of selenium in the testicular tissues induces degeneration which results in the active impairment of sperm motility as the first indication of impending infertility. This review paper investigates the role of selenium in male infertility. (author)

Resource allocation based on cost efficiency

DEFF Research Database (Denmark)

Dehnokhalaji, Akram; Ghiyasi, Mojtaba; Korhonen, Pekka

2017-01-01

-objective linear programming problem using two different strategies. First, we propose an RA model which keeps the cost efficiencies of units unchanged. This is done assuming fixed technical and allocative efficiencies. The approach is based on the assumption that the decision maker (DM) may not have big changes......In this paper, we consider a resource allocation (RA) problem and develop an approach based on cost (overall) efficiency. The aim is to allocate some inputs among decision making units (DMUs) in such way that their cost efficiencies improve or stay unchanged after RA. We formulate a multi...... in the structure of DMUs within a short term. The second strategy does not impose any restrictions on technical and allocative efficiencies. It guarantees that none of the cost efficiencies of DMUs get worse after RA, and the improvement for units is possible if it is feasible and beneficial. Two numerical...

Selenium Level and Dyslipidemia in Rural Elderly Chinese.

Directory of Open Access Journals (Sweden)

Liqin Su

Full Text Available Higher selenium level has been hypothesized to have the potential to reduce the risk of cardiovascular diseases including dyslipidemia. However, results from previous studies are inconsistent. This study aims to determine the association between selenium level and dyslipidemia in elderly Chinese with relatively low selenium status.A cross-sectional study of 1859 participants aged 65 or older from four rural counties in China was conducted. Serum total cholesterol (TC, triglycerides (TG, high density lipoprotein-cholesterol (HDLC and low-density lipoprotein-cholesterol (LDLC, nail selenium concentration and APOE genotype were measured in all subjects. The four types of dyslipidemia were defined as >5.17 mmol/L for High-TC, >1.69 mmol/L for High-TG, >3.36 mmol/L for High-LDLC, and <1.04 mmol/L for Low-HDLC according to Chinese Guidelines on Prevention and Treatment of Dyslipidemia in Adults. Logistic models adjusting for age, gender, APOE genotype, body mass index, alcohol consumption, smoking, physical activity, medication use for cardiovascular diseases were used to examine the relationship between selenium levels and the risk of dyslipidemia.Mean nail selenium concentration was 0.465 μg/gin this sample. Rates for High-TC, High-LDLC, High-TG, Low-HDLC were 18.13%, 13.23%, 12.21% and 32.76% respectively. Results from logistic models indicated that higher selenium levels were significantly associated with higher risk of High-TC, High-LDLC and lower risk of Low-HDLC adjusting for covariates (p < 0.0001. Compared with the lowest selenium quartile group, participants in selenium quartile groups 2, 3 and 4 had significantly higher rates of High-TC, High-LDLC, High-TG, and lower rate of Low-HDLC adjusting for covariates. No significant association was observed between selenium level and the risk of High-TG. APOEε4 carriers had higher rates of High-TC and High-LDLC. There was no interaction between selenium level and APOE with the rates of

Selenium supplementation for critically ill adults

DEFF Research Database (Denmark)

Allingstrup, Mikkel; Afshari, Arash

2015-01-01

BACKGROUND: Selenium is a trace mineral essential to health and has an important role in immunity, defence against tissue damage and thyroid function. Improving selenium status could help protect against overwhelming tissue damage and infection in critically ill adults. This Cochrane review...... was originally published in 2004 updated in 2007 and again 2015. OBJECTIVES: The primary objective was to examine the effect of nutrition supplemented with selenium or ebselen on mortality in critically ill patients.The secondary objective was to examine the relationship between selenium or ebselen...... supplementation and number of infections, duration of mechanical ventilation, length of intensive care unit stay and length of hospital stay. SEARCH METHODS: In this update, we searched the current issue of the Cochrane Central Register of Controlled Trials, the Cochrane Library (2014, Issue 5); MEDLINE (Ovid SP...

Impact of Selenium Supplementation on Growth and Selenium Accumulation on Spinach (Spinacia oleracea L. Plants

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Azadeh SAFFARYAZDI

2012-11-01

Full Text Available Selenium (Se has been proved to be an essential element for humans and animals. However, less is known about its effects on plants. A hydroponic experiment was carried out to investigate the effects of selenium on growth, selenium accumulation and some physiological characteristics of spinach (Spinacia oleracea L. cv. Missouri plants. Plants were grown in Hoagland nutrient solution amended with sodium selenite at 0 (control, 1, 2, 4, 6 and 10 mg.L-1 for 28 days. Growth parameters like shoot and root fresh weight, shoot and root dry weight, total dry weight, shoot and root length increased by 17, 15, 38, 19, 18 and 34 percent in response to the lowest concentration of Se (1 mg L-1, respectively over control. However, application of higher Se concentrations reduced these parameters as compared to control. Selenium up to 1 mg L-1 enhanced the levels of chlorophyll a and chlorophyll b by 87 and 165 percent, respectively, while higher levels of Se exert toxic effects. Total phenolic compounds in leaves increased directly by increasing the level of Se and plants treated with 10 mg. L-1 Se had the highest values. Selenium, sodium and calcium content increased, while potassium content decreased, by increasing selenium treatments. The highest amounts of Se in shoots (3.89 mg g-1 DW and roots (4.27 mg g-1 DW were obtained for the highest concentration of Se (10 mg L-1. The present results suggested the beneficial effects of Se on spinach growth and also its contribute ion to improving the nutritional value of spinach for livestock and human nutrition.

Impact of Selenium Supplementation on Growth and Selenium Accumulation on Spinach (Spinacia oleracea L. Plants

Directory of Open Access Journals (Sweden)

Azadeh SAFFARYAZDI

2012-11-01

Full Text Available Selenium (Se has been proved to be an essential element for humans and animals. However, less is known about its effects on plants. A hydroponic experiment was carried out to investigate the effects of selenium on growth, selenium accumulation and some physiological characteristics of spinach (Spinacia oleracea L. cv. �Missouri� plants. Plants were grown in Hoagland nutrient solution amended with sodium selenite at 0 (control, 1, 2, 4, 6 and 10 mg.L-1 for 28 days. Growth parameters like shoot and root fresh weight, shoot and root dry weight, total dry weight, shoot and root length increased by 17, 15, 38, 19, 18 and 34 percent in response to the lowest concentration of Se (1 mg L-1, respectively over control. However, application of higher Se concentrations reduced these parameters as compared to control. Selenium up to 1 mg L-1 enhanced the levels of chlorophyll a and chlorophyll b by 87 and 165 percent, respectively, while higher levels of Se exert toxic effects. Total phenolic compounds in leaves increased directly by increasing the level of Se and plants treated with 10 mg. L-1 Se had the highest values. Selenium, sodium and calcium content increased, while potassium content decreased, by increasing selenium treatments. The highest amounts of Se in shoots (3.89 mg g-1 DW and roots (4.27 mg g-1 DW were obtained for the highest concentration of Se (10 mg L-1. The present results suggested the beneficial effects of Se on spinach growth and also its contribute ion to improving the nutritional value of spinach for livestock and human nutrition.

The role of selenium in predicting preeclampsia

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Z Ghaemi

2013-10-01

Full Text Available Introduction: Preeclampsia is a common disorder that is a leading cause of perinatal and maternal morbidity and mortality; however its specific etiology has still remained obscure.The first step in preventing preeclampsia is early detection of women at risk. Since there is no valid and reliable screening test, appropriate diagnostic and screening tests are necessary, which are inexpensive, non-invasive and beneficial for pregnant women. Therefore, regarding the role of selenium as an antioxidant in the prevention preeclampsia, this study was designed which aimed to determine the prognostic value of plasma selenium levels in the diagnosis of preeclampsia in primigravida women Methods: In a nested case control design, a sample of 650 normal primigravida women of 24-28 weeks participated in the study. Subjects who involved the case group were followed up for 3 months and 38 were affected by preeclampsia. Blood samples were obtained from these 38patients as well as from 38 subjects as their matched controls. Moreover, the amount of selenium was measured by atomic absorption spectrometry. Results: The mean level of selenium in blood plasma of the cases was significantly lower than in their matched controls. The present study findings revealed that pregnant women with serum Se < 66.1 μg/L had a significantly increased risk of preeclampsia. Conclusion: Lower plasma selenium level in women destines to suffering from preeclampsia which confirms the destructive effect of selenium deficiency as an antioxidant in etiopathology of preeclampsia. Measurement of plasma selenium can improve the prediction of preeclampsia; thus, it seems that plasma selenium level test owns an acceptable sensitivity and specificity for predicting preeclampsia.

Genome-wide association study of serum selenium concentrations

DEFF Research Database (Denmark)

Gong, Jian; Hsu, Li; Harrison, Tabitha

2013-01-01

Selenium is an essential trace element and circulating selenium concentrations have been associated with a wide range of diseases. Candidate gene studies suggest that circulating selenium concentrations may be impacted by genetic variation; however, no study has comprehensively investigated...... this hypothesis. Therefore, we conducted a two-stage genome-wide association study to identify genetic variants associated with serum selenium concentrations in 1203 European descents from two cohorts: the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening and the Women’s Health Initiative (WHI). We...... tested association between 2,474,333 single nucleotide polymorphisms (SNPs) and serum selenium concentrations using linear regression models. In the first stage (PLCO) 41 SNPs clustered in 15 regions had p

Spectrophotometric evaluation of selenium binding by Saccharomyces cerevisiae ATCC MYA-2200 and Candida utilis ATCC 9950 yeast.

Science.gov (United States)

Kieliszek, Marek; Błażejak, Stanisław; Płaczek, Maciej

2016-05-01

In this study, the ability of selenium binding the biomas of Saccharomyces cerevisiae ATCC MYA-2200 and Candida utilis ATCC 9950 was investigated. Sodium selenite(IV) salts were added to the experimental media at concentrations of 10, 20, 40, and 60 mg Se(4+) L(-1). In the tested concentration range, one concentration reported a significant reduction in the biomass yield of both yeast strains. Intense growth was observed for C. utilis yeast, which reached the highest biomass yield of 15 gd.w.L(-1) after 24h cultivation in the presence of 10mg Se(4+) L(-1). Based on the use of spectrophotometric method for the determination of selenium content by using Variamine Blue as a chromogenic agent, efficient accumulation of this element in the biomass of the investigated yeast was observed. The highest amount of selenium, that is, 5.64 mg Se(4+)gd.w.(-1), was bound from the environment by S. cerevisiae ATCC MYA-2200 cultured in the presence of 60 mg Se(4+) L(-1) medium 72h Slightly less amount, 5.47 mg Se(4+) gd.w.(-1), was absorbed by C. utilis ATCC 9950 during similar cultural conditions. Based on the results of the biomass yield and the use of selenium from the medium, it can be observed that yeasts of the genus Candida are more efficient in binding this element, and this property finds practical application in the production of selenium-enriched yeast. Copyright © 2016 Elsevier GmbH. All rights reserved.

Interspecific and intraspecific variation in selenium:mercury molar ratios in saltwater fish from the Aleutians: Potential protection on mercury toxicity by selenium

Science.gov (United States)

Burger, Joanna; Gochfeld, Michael; Jeitner, Christian; Donio, Mark; Pittfield, Taryn

2014-01-01

A number of factors affect the consumption risk from mercury in fish, including mercury levels, seasonal patterns of mercury concentrations, human consumption patterns, and sensitive populations (e.g. pregnant women, fetuses, young children, and yet unknown genetic factors). Recently the protective effects of selenium on methylmercury toxicity have been publicized, particularly for saltwater fish. We examine levels of mercury and selenium in several species of fish and seabirds from the Aleutians (Alaska), determine selenium:mercury molar ratios, and examine species-specific and individual variation in the ratios as a means of exploring the use of the ratio in risk assessment and risk management. Variation among species was similar for mercury and selenium. There was significant inter-specific and intraspecific variation in selenium:mercury molar ratios for fish, and for birds. The mean selenium:mercury molar ratios for all fish and bird species were above 1, meaning there was an excess of selenium relative to mercury. It has been suggested that an excess of selenium confers some protective advantage for salt water fish, although the degree of excess necessary is unclear. The selenium:mercury molar ratio was significantly correlated negatively with total length for most fish species, but not for dolly varden. Some individuals of Pacific cod, yellow irish lord, rock greenling, Pacific halibut, dolly varden, and to a lesser extent, flathead sole, had selenium:mercury ratios below 1. No bird muscle had an excess of mercury (ratio below 1), and only glaucous-winged gull and pigeon guillemot had ratios between 1 and 5. There was a great deal of variation in selenium:mercury molar ratios within fish species, and within bird species, making it difficult and impractical to use these ratios in risk assessment or management, for fish advisories, or for consumers, particularly given the difficulty of interpreting the ratios. PMID:22664537

Chemical state of mercury and selenium in sewage sludge ash based P-fertilizers

Energy Technology Data Exchange (ETDEWEB)

Vogel, Christian, E-mail: cv.vogel@yahoo.de [Division 4.4 Thermochemical Residues Treatment and Resource Recovery, Bundesanstalt für Materialforschung und −prüfung (BAM), Unter den Eichen 87, 12205 Berlin (Germany); Krüger, Oliver; Herzel, Hannes [Division 4.4 Thermochemical Residues Treatment and Resource Recovery, Bundesanstalt für Materialforschung und −prüfung (BAM), Unter den Eichen 87, 12205 Berlin (Germany); Amidani, Lucia [ESRF—The European Synchrotron, 71 Avenue des Martyrs, 38000 Grenoble (France); Adam, Christian [Division 4.4 Thermochemical Residues Treatment and Resource Recovery, Bundesanstalt für Materialforschung und −prüfung (BAM), Unter den Eichen 87, 12205 Berlin (Germany)

2016-08-05

Highlights: • Mercury bonded to carbon/organic material was detected in some sewage sludge ashes. • After thermochemcial treatment some mercury remains stabilized in the SSA matrix. • Analysis of the chemical state of mercury and selenium in highly diluted samples. - Abstract: Phosphorus-fertilizers from secondary resources such as sewage sludge ash (SSA) will become more important in the future as they could substitute conventional fertilizers based on the nonrenewable resource phosphate rock. Thermochemical approaches were developed which remove heavy metals from SSA prior to its fertilizer application on farmlands. We analyzed the chemical state of mercury and selenium in SSA before and after thermochemical treatment under different conditions for P-fertilizer production by X-ray absorption near edge structure (XANES) spectroscopy. In some incineration plants the mercury loaded carbon adsorber from off-gas cleaning was collected together with the SSA for waste disposal. SSAs from those plants contained mercury mainly bound to carbon/organic material. The other SSAs contained inorganic mercury compounds which are most probably stabilized in the SSA matrix and were thus not evaporated during incineration. During thermochemical treatment, carbon-bound mercury was removed quantitatively. In contrast, a certain immobile fraction of inorganic mercury compounds remained in thermochemically treated SSA, which were not clearly identified. HgSe might be one of the inorganic compounds, which is supported by results of Se K-edge XANES spectroscopy. Furthermore, the chemical state of selenium in the SSAs was very sensitive to the conditions of the thermochemical treatment.

Selenium Nanoparticles for Stress-Resilient Fish and Livestock

Science.gov (United States)

Sarkar, Biplab; Bhattacharjee, Surajit; Daware, Akshay; Tribedi, Prosun; Krishnani, K. K.; Minhas, P. S.

2015-09-01

The fisheries and livestock sectors capture the highest share of protein-rich animal food and demonstrate accelerated growth as an agriculture subsidiary. Environmental pollution, climate change, as well as pathogenic invasions exert increasing stress impacts that lead the productivity momentum at a crossroads. Oxidative stress is the most common form of stress phenomenon responsible for the retardation of productivity in fisheries and livestock. Essential micronutrients play a determinant role in combating oxidative stress. Selenium, one of the essential micronutrients, appears as a potent antioxidant with reduced toxicity in its nanoscale form. In the present review, different methods of synthesis and characterization of nanoscale selenium have been discussed. The functional characterization of nano-selenium in terms of its effect on growth patterns, feed digestibility, and reproductive system has been discussed to elucidate the mechanism of action. Moreover, its anti-carcinogenic and antioxidant potentiality, antimicrobial and immunomodulatory efficacy, and fatty acid reduction in liver have been deciphered as the new phenomena of nano-selenium application. Biologically synthesized nano-selenium raises hope for pharmacologically enriched, naturally stable nanoscale selenium with high ecological viability. Hence, nano-selenium can be administered with commercial feeds for improvising stress resilience and productivity of fish and livestock.

Substoichiometric determination of selenium with potassium ethyl xanthate

International Nuclear Information System (INIS)

Chandrasekhar Reddy, P.; Polaiah, B.; Rangamannar, B.

1989-01-01

A substoichiometric radiochemical method was developed for the determination of selenium with potassium ethyl xanthate. The selenium ethyl xanthate complex formed was extracted into chloroform from borate buffer at pH 5. The effect of foreign ions on the extraction was studied. Microgram quantities of selenium could be conveniently determined with a fair degree of accuracy. The method was successfully applied for the determination of selenium content in food stuffs such as 'Jaggery' and 'Wheat powder'. (author) 4 refs.; 3 figs

Determination of human and Sprague-Dawley rat trimethylseleonium ion and total selenium urine concentrations from endogenous body selenium pool by neutron activation analysis

International Nuclear Information System (INIS)

Blotcky, A.J.; Claassen, J.P.; Rack, E.P.

1992-01-01

This study determined trimethylselenonium ion [TMSe,(CH 3 ) 3 Se + ] and total organic selenium cationic species urinary excretion values for healthy human subjects and Sprague-Dawley rats fed regular diets. The only source of TMSe was from the endogenous selenium body pool. Total selenium concentration in urine was determined by instrumental neutron activation analysis. TMSe and total selenium cationic species concentrations and percent of total selenium urine excretion were determined by chemical neutron activation analysis and coupled anion-cation exchange chromatography and anion-exchange chromatography, respectively. Within experimental error, mean values for TMSe and cationic species as percent selenium were comparable for both human subjects and Sprague-Dawley rats. This study suggested that TMSe excreated in urine by healthy human subjects and Sprague-Dawley rats fed a normal diet is not a minor but a general metabolite of selenium ingested in a normal diet. (author) 27 refs.; 1 fig.; 2 tabs

NAIL KERATIN AS MONITOR-TISSUE FOR SELENIUM EXPOSURE

NARCIS (Netherlands)

VANNOORD, PAH; MAAS, MJ; DEBRUIN, M

1992-01-01

Nail clippings might provide a way to monitor exposure to selenium in the recent past of an individual, since a clipping collected from a toe would reflect exposures months before actual clipping date. The relation between levels of exogenous selenium exposure and selenium levels in nail keratin was

Lignosulfonate-stabilized selenium nanoparticles and their deposition on spherical silica.

Science.gov (United States)

Modrzejewska-Sikorska, Anna; Konował, Emilia; Klapiszewski, Łukasz; Nowaczyk, Grzegorz; Jurga, Stefan; Jesionowski, Teofil; Milczarek, Grzegorz

2017-10-01

We report a novel room-temperature synthesis of selenium nanoparticles, which for the first time uses lignosulfonate as a stabilizer. Various lignosulfonates obtained both from hardwood and softwood were tested. Selenium oxide was used as the precursor of zero-valent selenium. Three different reducers were tested - sodium borohydride, hydrazine and ascorbic acid - and the latter proved most effective in terms of the particle size and stability of the final colloid. The lignosulfonate-stabilized selenium nanoparticles had a negative zeta potential, dependent on pH, which for some lignosulfonates reached -50mV, indicating the excellent stability of the colloid. When spherical silica particles were introduced to the synthesis mixture, selenium nanoparticles were deposited on their surface. Additionally, star-like structures consisting of sharp selenium needles with silica cores were observed. After drying, the selenium-functionalized silica had a grey metallic hue. The method reported here is simple and cost-effective, and can be used for the preparation of large quantities of selenium colloids or the surface modification of other materials with selenium. Copyright © 2017 Elsevier B.V. All rights reserved.

Reproduction in eastern screech-owls fed selenium

Science.gov (United States)

Wiemeyer, Stanley N.; Hoffman, D.J.

1996-01-01

Raptors are occasionally exposed to excessive selenium from contaminated prey, but the effects of this exposure on reproduction are unknown. Therefore, we fed captive eastern screech-owls (Otus asio) diets containing 0, 4.4, or 13.2 ppm (wet wt) added selenium in the form of seleno-DL-methionine. Adult mass at sacrifice and reproductive success of birds receiving 13.2 ppm selenium were depressed (P biochemistries indicative of oxidative stress were affected (P < 0.05) in 5-day-old nestlings from parents fed 4.4 ppm selenium and included a 19% increase in glutathione peroxidase activity, a 43% increase in the ratio of oxidized glutathione (GSSG) to reduced glutathione (GSH), and a 17% increase in lipid peroxidation. Based on reproductive effects relative to dietary exposure, sensitivity of eastern screech-owls to selenium was similar to that of black-crowned night-herons (Nycticorax nycticorax) but less than that of mallards (Anas platyrhynchos).

Selenium Homeostasis and Clustering of Cardiovascular Risk Factors: A Systematic Review.

Science.gov (United States)

Gharipour, Mojgan; Sadeghi, Masoumeh; Behmanesh, Mehrdad; Salehi, Mansour; Nezafati, Pouya; Gharpour, Amin

2017-10-23

  Selenium is a trace element required for a range of cellular functions. It is widely used for the biosynthesis of the unique amino acid selenocysteine [Sec], which is a structural element of selenoproteins. This systematic review focused on the possible relation between selenium and metabolic risk factors. The literature was searched via PubMed, Scopus, ISI Web of Science, and Google Scholar. Searches were not restricted by time or language. Relevant studies were selected in three phases. After an initial quality assessment, two reviewers extracted all the relevant data, whereas the third reviewer checked their extracted data. All evidence came from experimental and laboratory studies. Selenoprotein P is the best indicator for selenium nutritional levels. In addition, high levels of selenium may increase the risk of metabolic syndrome while the lack of sufficient selenium may also promote metabolic syndrome. selenium supplementation in subjects with sufficient serum selenium levels has a contrary effect on blood pressure, LDL, and total cholesterol. According to the bioavailability of different types of selenium supplementation such as selenomethionine, selenite and selenium-yeast, it seems that the best nutritional type of selenium is selenium-yeast. Regarding obtained results of longitudinal studies and randomized controlled trials, selenium supplementation should not be recommended for primary or secondary cardio-metabolic risk prevention in populations with adequate selenium status.

Advanced prostate cancer risk in relation to toenail selenium levels

NARCIS (Netherlands)

Geybels, M.S.; Verhage, B.A.J.; Schooten, F.J. van; Goldbohm, A.; Brandt, P.A. van den

2013-01-01

BACKGROUND: Selenium may prevent advanced prostate cancer (PCa), but most studies on this topic were conducted in populations with moderate to high selenium status. We investigated the association of toenail selenium, reflecting long-term selenium exposure, and advanced PCa risk in a population from

Selenium content in wheat and estimation of the selenium daily intake in different regions of Algeria

International Nuclear Information System (INIS)

Beladel, B.; Nedjimi, B.; Mansouri, A.; Tahtat, D.; Belamri, M.; Tchanchane, A.; Khelfaoui, F.; Benamar, M.E.A.

2013-01-01

In this work, we have measured the selenium content in wheat produced locally in eight different regions of Algeria from east to west, and we have established the annual consumption of selenium for five socio-professional categories. Instrumental neutron activation analysis is used. The selenium levels in wheat samples varied from 21 (Tiaret) to 153 μg/kg (Khroub), with a mean value about 52 μg/kg. The mean of selenium daily consumption from ingestion of wheat per person in the eight regions varied from 32 to 52 μg/day which is close to the minimal FAO recommendation. - Highlights: ► Cereals and cereal products represent a staple food in Algeria. ► The objective of this study is to determine the Se intake in wheat produced locally. ► The concentration of Se in the wheat reflects the level of the Se in regional soils. ► The mean of Se daily consumption is close to the minimal WHO/FAO recommendation.

Investigation of electrical noise in selenium-immersed thermistor bolometers

Science.gov (United States)

Tarpley, J. L.; Sarmiento, P. D.

1980-01-01

The selenium immersed, thermistor bolometer, IR detector failed due to spurious and escalating electrical noise outburst as a function of time at elevated temperatures during routine ground based testing in a space simulated environment. Spectrographic analysis of failed bolometers revealed selenium pure zones in the insulating selenium arsenic (Se-As) glass film which surrounds the active sintered Mn, Ni, Co oxide flake. The selenium pure film was identified as a potentially serious failure mechanism. Significant changes were instituted in the manufacturing techniques along with more stringent process controls which eliminated the selenium pure film and successfully produced 22study bolometers.

Supplementation with Selenium and Coenzyme Q10 Reduces Cardiovascular Mortality in Elderly with Low Selenium Status. A Secondary Analysis of a Randomised Clinical Trial

Science.gov (United States)

Alexander, Jan; Aaseth, Jan

2016-01-01

Background Selenium is needed by all living cells in order to ensure the optimal function of several enzyme systems. However, the selenium content in the soil in Europe is generally low. Previous reports indicate that a dietary supplement of selenium could reduce cardiovascular disease but mainly in populations in low selenium areas. The objective of this secondary analysis of a previous randomised double-blind placebo-controlled trial from our group was to determine whether the effects on cardiovascular mortality of supplementation with a fixed dose of selenium and coenzyme Q10 combined during a four-year intervention were dependent on the basal level of selenium. Methods In 668 healthy elderly individuals from a municipality in Sweden, serum selenium concentration was measured. Of these, 219 individuals received daily supplementation with selenium (200 μg Se as selenized yeast) and coenzyme Q10 (200 mg) combined for four years. The remaining participants (n = 449) received either placebo (n = 222) or no treatment (n = 227). All cardiovascular mortality was registered. No participant was lost during a median follow-up of 5.2 years. Based on death certificates and autopsy results, all mortality was registered. Findings The mean serum selenium concentration among participants at baseline was low, 67.1 μg/L. Based on the distribution of selenium concentration at baseline, the supplemented group was divided into three groups; 85 μg/L (45 and 90 percentiles) and the remaining participants were distributed accordingly. Among the non-treated participants, lower cardiovascular mortality was found in the high selenium group as compared with the low selenium group (13.0% vs. 24.1%; P = 0.04). In the group with the lowest selenium basal concentration, those receiving placebo or no supplementation had a mortality of 24.1%, while mortality was 12.1% in the group receiving the active substance, which was an absolute risk reduction of 12%. In the middle selenium concentration

Understanding selenium biogeochemistry in engineered ecosystems

NARCIS (Netherlands)

Jain, Rohan; Hullebusch, Van Eric D.; Lenz, Markus; Farges, François

2017-01-01

Selenium is used extensively in many industries, and it is necessary for human nutrition. On the other hand, it is also toxic at slightly elevated concentrations. With the advent of industrialisation, selenium concentrations in the environment due to anthropogenic activities have increased.

Selenium and Its Supplementation in Cardiovascular Disease—What do We Know?

Directory of Open Access Journals (Sweden)

Carina Benstoem

2015-04-01

Full Text Available The trace element selenium is of high importance for many of the body’s regulatory and metabolic functions. Balanced selenium levels are essential, whereas dysregulation can cause harm. A rapidly increasing number of studies characterizes the wide range of selenium dependent functions in the human body and elucidates the complex and multiple physiological and pathophysiological interactions of selenium and selenoproteins. For the majority of selenium dependent enzymes, several biological functions have already been identified, like regulation of the inflammatory response, antioxidant properties and the proliferation/differentiation of immune cells. Although the potential role of selenium in the development and progression of cardiovascular disease has been investigated for decades, both observational and interventional studies of selenium supplementation remain inconclusive and are considered in this review. This review covers current knowledge of the role of selenium and selenoproteins in the human body and its functional role in the cardiovascular system. The relationships between selenium intake/status and various health outcomes, in particular cardiomyopathy, myocardial ischemia/infarction and reperfusion injury are reviewed. We describe, in depth, selenium as a biomarker in coronary heart disease and highlight the significance of selenium supplementation for patients undergoing cardiac surgery.

Selenium and Its Supplementation in Cardiovascular Disease—What do We Know?

Science.gov (United States)

Benstoem, Carina; Goetzenich, Andreas; Kraemer, Sandra; Borosch, Sebastian; Manzanares, William; Hardy, Gil; Stoppe, Christian

2015-01-01

The trace element selenium is of high importance for many of the body’s regulatory and metabolic functions. Balanced selenium levels are essential, whereas dysregulation can cause harm. A rapidly increasing number of studies characterizes the wide range of selenium dependent functions in the human body and elucidates the complex and multiple physiological and pathophysiological interactions of selenium and selenoproteins. For the majority of selenium dependent enzymes, several biological functions have already been identified, like regulation of the inflammatory response, antioxidant properties and the proliferation/differentiation of immune cells. Although the potential role of selenium in the development and progression of cardiovascular disease has been investigated for decades, both observational and interventional studies of selenium supplementation remain inconclusive and are considered in this review. This review covers current knowledge of the role of selenium and selenoproteins in the human body and its functional role in the cardiovascular system. The relationships between selenium intake/status and various health outcomes, in particular cardiomyopathy, myocardial ischemia/infarction and reperfusion injury are reviewed. We describe, in depth, selenium as a biomarker in coronary heart disease and highlight the significance of selenium supplementation for patients undergoing cardiac surgery. PMID:25923656

Biological effects of selenium and relationships with carcinogenesis

Energy Technology Data Exchange (ETDEWEB)

Diplock, A.T.

1984-01-01

Selenium is an element that is both essential, at low levels of dietary intake, and toxic, at high levels, to man and a wide range of animals. The purpose of the communication is to review the evidence for the involvement of hyper- and hypo-selenosis in the etiology of cancer. High levels of selenium intake have been blamed for an increase in cancer, dental caries and an array of other conditions. Critical evaluation of the evidence, however, leads to the conclusion that such claims have little substance. On the other hand, low levels of selenium intake may be associated with an increased incidence of certain forms of cancer and there appears to be an inverse relationship between blood selenium levels and cancer death rate in the US. Keshan Disease, in the People's Republic of China has only been shown to occur in populations severely depleted of selenium. In well nourished populations there is no evidence to indicate that selenium supplements have any prophylactic or therapeutic benefit against human diseases such as cancer, cardiovascular disease or cystic fibrosis. 33 references.

Nuclear-based methods for the study of selenium

International Nuclear Information System (INIS)

Spyrou, N.M.; Akanle, O.A.; Dhani, A.

1988-01-01

The essentiality of selenium to the human being and in particular its deficiency state, associated with prolonged inadequate dietary intake, have received considerable attention. In addition, the possible relationship between selenium and cancer and the claim that selenium may possess cancer-prevention properties have focused research effort. It has been observed in a number of studies on laboratory animals that selenium supplementation protects the animals against carcinogen-induced neoplastic growth in various organ sites, reduces the incidence of spontaneous mammary tumors, and suppresses the growth of transplanted tumor cells. In these research programs on the relationship between trace element levels and senile dementia and depression and the elemental changes in blood associated with selenium supplementation in a normal group of volunteers, it became obvious that in addition to establishing normal levels of elements in the population of interest, there was a more fundamental requirement for methods to be developed that would allow the study of the distribution of selenium in the body and its binding sites. The authors propose emission tomography and perturbed angular correlation as techniques worth exploring

Molecular neutron activation analysis of selenium metabolites in urine

International Nuclear Information System (INIS)

Blotcky, A.J.; Hansen, G.T.; Ebrahim, A.; Rack, E.P.

1988-01-01

Because of the biological importance of selenium in living biological systems, various analytical procedures have been developed for analysis of microquantities of elemental selenium, in urine, serum, and tissue. For urine selenium, these include atomic absorption spectrometry, solution absorption spectrometry, solution fluorescence spectrometry, volumetry, and neutron activation analysis. Of equal or greater importance is the determination of selenium metabolites present in urine for the purpose of describing the biological pathways for the metabolism of selenium in living organisms. While it is known from previous studies that trimethylselenonium ion (TMSe) is a major metabolite in urine, probably the result of reduction and methylation reaction, there are no definitive results in the literature indicating the nature or quantity of other selenium metabolic products in urine. Early techniques to measure TMSe levels in urine involved the use of the radiotracer 75 Se. Because of the long biological half-life of selenium and issues of radiation exposure, its use in humans has been limited. In this paper, the authors report the experimental procedure for the determination of total selenoamino acid concentration in urine and present total selenium values, and, where applicable, TMSe, SeO 2- 3 , and total selenoamino acid concentrations in the urine of normal and diseased subjects

Nuclear transformations studies in selenium isotopes

International Nuclear Information System (INIS)

Lopez M, B.E.

1976-01-01

A compilation is made with regard to the chemical effects produced by nuclear transformations, such as the chemical effects of the beta decay and the chemical effects of the reaction (n,γ) in selenium radioisotopes. As a particular case the chemical effect of the isomeric transition of sup(81m)Se(VI) in potassium selenate crystals marked with radioactive selenium is studied experimentally and the method of adsorption in activated carbon is applied for the analytical separation of the traces of the nuclear isomer tetravalent sup(81b)Se(IV) of one fraction which contains the mixture of the selenium radioisotopes. (author)

Serum selenium level and risk of lung cancer mortality

DEFF Research Database (Denmark)

Suadicani, P; Hein, H O; Gyntelberg, F

2011-01-01

Serum selenium has been implicated as a risk factor for lung cancer, but the issue remains unsettled. We tested in a cohort of 3,333 males aged 53 to 74 years the hypothesis that a low serum selenium would be associated with an increased risk of lung cancer mortality.During 16 years, 167 subjects(5.......1%) died from lung cancer; 48 males (5.0%) among males with low serum selenium, 0.4-1.0 μmol·l(-1), n=965, 57 males (5.1%) among males with medium serum selenium, 1.1-1.2 μmol·l(-1), n=1,141, and 62 males (5.1%) among males with high serum selenium, 1.3-3.0 μmol·l(-1), n=1,227. After adjustment for age...... (chronic bronchitis and peak flow), referencing the lowest level of serum selenium HRs were 1.17(0.79-1.75), and 1.43(0.96-2.14), respectively. Among heavy smokers a high serum selenium was associated with a significantly increased risk of lung cancer mortality after taking into account all potential...

Chunk-Based Energy Efficient Resource Allocation in OFDMA Systems

Directory of Open Access Journals (Sweden)

Yong Li

2013-01-01

Full Text Available Energy efficiency (EE capacity analysis of the chunk-based resource allocation is presented by considering the minimum spectrum efficiency (SE constraint in downlink multiuser orthogonal frequency division multiplexing (OFDM systems. Considering the minimum SE requirement, an optimization problem to maximize EE with limited transmit power is formulated over frequency selective channels. Based on this model, a low-complexity energy efficient resource allocation is proposed. The effects of system parameters, such as the average channel gain-to-noise ratio (CNR and the number of subcarriers per chunk, are evaluated. Numerical results demonstrate the effectiveness of the proposed scheme for balancing the EE and SE.

ANALYSIS OF RESOURCE USE EFFICIENCY AMONG SOYBEAN ...

African Journals Online (AJOL)

2015-02-25

Feb 25, 2015 ... KEYWORDS: Analysis, Resource use efficiency, Farmers, production function analysis, Benue, Nigeria. ... Soybean seeds also contain about 20% oil on a dry matter basis, and this ..... Manual for training in Seed Technology.

Speciation of Selenium in Stream Insects Using X-Ray Absorption Spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Andrahennadi, R.; Wayland, M.; Pickering, I.J.

2009-05-28

Selenium contamination in the environment is a widespread problem affecting insects and other wildlife. Insects occupy a critical middle link and aid in trophic transfer of selenium in many terrestrial and freshwater food chains, but the mechanisms of selenium uptake through the food chain are poorly understood. In particular, biotransformation of selenium by insects into different chemical forms will greatly influence how toxic or benign the selenium is to that organism or to its predators. We have used X-ray absorption spectroscopy (XAS) to identify the chemical form of selenium in insects inhabiting selenium contaminated streams near Hinton, Alberta (Canada). Selenium K near-edge spectra indicate a variability of selenium speciation among the insects that included mayflies (Ephemeroptera), stoneflies (Plecoptera), caddisflies (Trichoptera), and craneflies (Diptera). Higher percentages of inorganic selenium were observed in primary consumers, detritivores, and filter feeders than in predatory insects. Among the organic forms of selenium, organic selenides constituted a major fraction in most organisms. A species modeled as trimethylselenonium was observed during the pupal stage of caddisflies. These results provide insights into how the insects cope with their toxic cargo, including how the selenium is biotransformed into less toxic forms and how it can be eliminated from the insects. More broadly, this study demonstrates the strengths of XAS to probe the effects of heavy elements at trace levels in insects from the field.

Speciation of selenium in stream insects using X-ray absorption spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Ruwandi Andrahennadi; Mark Wayland; Ingrid J. Pickering [University of Saskatchewan, Saskatoon, SK (Canada). Department of Geological Sciences

2007-11-15

Selenium contamination in the environment is a widespread problem affecting insects and other wildlife. Insects occupy a critical middle link and aid in trophic transfer of selenium in many terrestrial and freshwater food chains, but the mechanisms of selenium uptake through the food chain are poorly understood. In particular, biotransformation of selenium by insects into different chemical forms will greatly influence how toxic or benign the selenium is to that organism or to its predators. We have used X-ray absorption spectroscopy (XAS) to identify the chemical form of selenium in insects inhabiting selenium contaminated streams near Hinton, Alberta (Canada). Selenium K near-edge spectra indicate a variability of selenium speciation among the insects that included mayflies (Ephemeroptera), stoneflies (Plecoptera), caddisflies (Trichoptera), and craneflies (Diptera). Higher percentages of inorganic selenium were observed in primary consumers, detritivores, and filter feeders than in predatory insects. Among the organic forms of selenium, organic selenides constituted a major fraction in most organisms. A species modeled as trimethylselenonium was observed during the pupal stage of caddisflies. These results provide insights into how the insects cope with their toxic cargo, including how the selenium is biotransformed into less toxic forms and how it can be eliminated from the insects. More broadly, this study demonstrates the strengths of XAS to probe the effects of heavy elements at trace levels in insects from the field.

Bio-transformation of selenium in Se-enriched bacterial strains of Lactobacillus casei.

Science.gov (United States)

Kurek, Eliza; Ruszczyńska, Anna; Wojciechowski, Marcin; Łuciuk, Anna; Michalska-Kacymirow, Magdalena; Motyl, Ilona; Bulska, Ewa

Selenium is an element of very great importance for the proper functioning of the human body, mainly due to its antioxidant properties. Selenium exhibits a preventive effect in the case of cardiovascular disease, the immune system, male infertility and inhibits the toxic action of other agents. Selenium is important for Hashimoto's disease. Intake of selenium in the diet slows the aging process. The biological and toxicological effects of selenium strongly depend on its chemical form. Some organisms for example: plant, yeast, are capable of metabolizing low bioavailable selenium compounds (inorganic selenium) into its high bioavailable forms (organic selenium). The aim of this study was to investigate the bio-transformation of selenium by Lactobacillus bacteria towards the characterisation of selenium metabolites. The speciation of selenium was evaluated by high performance liquid chromatography with inductively coupled plasma mass spectrometry detector. The extraction of selenium species from lyophilized bacteria was executed with water, the mixture of lipase and protease, as well as lisozyme and sodium dodecyl sulphate. All investigated bacteria strains cultivated in the presence of Na2SeO3 effectively uptake selenium. Surprisingly, none of the applied extraction media exhibited a strong power to release the majority of the uptaken selenium compounds. Thus a maximum of 10% of the selenium was extracted from bacteria exposed to the enzymes. However, it was found that Lactobacillus bacteria are able to metabolize inorganic ions of selenium (IV) into Se-methionine, Se-methyloselenocysteine and other unidentified forms. The study confirmed the ability of probiotic bacteria to biotransform inorganic selenium into its organic derivatives. Therefore, Se-enriched bacteria can be considered as an addition to the functional food. selenium speciation, extraction procedure, Lactobacillus casei bacteria, Lactic acid bacteria (LAB), HPLC ICP-MS, functional food.

Recycling of high purity selenium from CIGS solar cell waste materials

Energy Technology Data Exchange (ETDEWEB)

Gustafsson, Anna M.K., E-mail: anna.gustafsson@chalmers.se; Foreman, Mark R.StJ.; Ekberg, Christian

2014-10-15

Highlights: • A new method for recycling of selenium from CIGS solar cell materials is presented. • Separation of selenium as selenium dioxide after heating in oxygen atmosphere. • Complete selenium separation after oxidation of <63 μm particles at 800 °C for 1 h. • After reduction of selenium dioxide the selenium purity was higher than 99.999 wt%. - Abstract: Copper indium gallium diselenide (CIGS) is a promising material in thin film solar cell production. To make CIGS solar cells more competitive, both economically and environmentally, in comparison to other energy sources, methods for recycling are needed. In addition to the generally high price of the material, significant amounts of the metals are lost in the manufacturing process. The feasibility of recycling selenium from CIGS through oxidation at elevated temperatures was therefore examined. During oxidation gaseous selenium dioxide was formed and could be separated from the other elements, which remained in solid state. Upon cooling, the selenium dioxide sublimes and can be collected as crystals. After oxidation for 1 h at 800 °C all of the selenium was separated from the CIGS material. Two different reduction methods for reduction of the selenium dioxide to selenium were tested. In the first reduction method an organic molecule was used as the reducing agent in a Riley reaction. In the second reduction method sulphur dioxide gas was used. Both methods resulted in high purity selenium. This proves that the studied selenium separation method could be the first step in a recycling process aimed at the complete separation and recovery of high purity elements from CIGS.

Laser-Induced Gas-Phase Pyrolysis of Dimethyl Selenium: Chemical Deposition of Selenium and Poly(selenoformaldehyde)

Czech Academy of Sciences Publication Activity Database

Pokorná, Dana; Urbanová, Markéta; Bastl, Zdeněk; Šubrt, Jan; Pola, Josef

2004-01-01

Roč. 71, č. 2 (2004), s. 635-644 ISSN 0165-2370 R&D Projects: GA AV ČR IAA4072107; GA MŠk OC 523.60 Institutional research plan: CEZ:AV0Z4072921; CEZ:AV0Z4032918; CEZ:AV0Z4040901 Keywords : dimethyl selenium * laser pyrolysis * selenium films Subject RIV: CC - Organic Chemistry Impact factor: 1.352, year: 2004

Biomarkers of Selenium Chemoprevention of Prostate Cancer

National Research Council Canada - National Science Library

Dong, Yan

2003-01-01

The purpose of the present study was to examine the mechanism of selenium growth inhibition in PC-3 human prostate cancer cells Selenium retarded cell cycle progression at multiple transition points...

The Effect on Selenium Concentrations of a Randomized Intervention with Fish and Mussels in a Population with Relatively Low Habitual Dietary Selenium Intake

DEFF Research Database (Denmark)

Outzen, Malene; Tjønneland, Anne; Larsen, Erik Huusfeldt

2015-01-01

Selenium status of the Danish population is below that assumed optimal for the suggested protective effects against chronic diseases, including certain cancers. Fish and shellfish are important dietary sources of selenium in Denmark. We investigated the effect of increased fish and mussel intake...... on selenium blood concentrations in a population with relatively low habitual dietary selenium intake. We randomly assigned 102 healthy men and women (all non-smokers) aged 48-76 years to an intervention group (n = 51) or a control group (n = 51). Intervention participants received 1000 g fish and mussels....../week for 26 weeks (similar to 50 mu g selenium/day). Controls received no intervention. Non-fasting blood samples were taken and whole blood selenium was determined using inductively coupled plasma-mass spectrometry (ICP-MS), and plasma selenoprotein P (SelP) was determined by high performance liquid...

No Evidence of Trade-Off between Farm Efficiency and Resilience: Dependence of Resource-Use Efficiency on Land-Use Diversity.

Directory of Open Access Journals (Sweden)

Helena Kahiluoto

Full Text Available Efficiency in the use of resources stream-lined for expected conditions could lead to reduced system diversity and consequently endanger resilience. We tested the hypothesis of a trade-off between farm resource-use efficiency and land-use diversity. We applied stochastic frontier production models to assess the dependence of resource-use-efficiency on land-use diversity as illustrated by the Shannon-Weaver index. Total revenue in relation to use of capital, land and labour on the farms in Southern Finland with a size exceeding 30 ha was studied. The data were extracted from the Finnish Profitability Bookkeeping data. Our results indicate that there is either no trade-off or a negligible trade-off of no economic importance. The small dependence of resource-use efficiency on land-use diversity can be positive as well as negative. We conclude that diversification as a strategy to enhance farm resilience does not necessarily constrain resource-use efficiency.

Genome-Wide Association Study of Serum Selenium Concentrations

Directory of Open Access Journals (Sweden)

Ulrike Peters

2013-05-01

Full Text Available Selenium is an essential trace element and circulating selenium concentrations have been associated with a wide range of diseases. Candidate gene studies suggest that circulating selenium concentrations may be impacted by genetic variation; however, no study has comprehensively investigated this hypothesis. Therefore, we conducted a two-stage genome-wide association study to identify genetic variants associated with serum selenium concentrations in 1203 European descents from two cohorts: the Prostate, Lung, Colorectal, and Ovarian (PLCO Cancer Screening and the Women’s Health Initiative (WHI. We tested association between 2,474,333 single nucleotide polymorphisms (SNPs and serum selenium concentrations using linear regression models. In the first stage (PLCO 41 SNPs clustered in 15 regions had p < 1 × 10−5. None of these 41 SNPs reached the significant threshold (p = 0.05/15 regions = 0.003 in the second stage (WHI. Three SNPs had p < 0.05 in the second stage (rs1395479 and rs1506807 in 4q34.3/AGA-NEIL3; and rs891684 in 17q24.3/SLC39A11 and had p between 2.62 × 10−7 and 4.04 × 10−7 in the combined analysis (PLCO + WHI. Additional studies are needed to replicate these findings. Identification of genetic variation that impacts selenium concentrations may contribute to a better understanding of which genes regulate circulating selenium concentrations.

Erythrocytic glutathione peroxidase: Its relationship to plasma selenium in man

International Nuclear Information System (INIS)

Perona, G.; Cellerino, R.; Guidi, G.C.; Moschini, G.; Stievano, B.M.; Tregnaghi, C.

1977-01-01

Erythrocytic glutathione-peroxidase (GSH-Px) activity and plasma selenium concentrations were measured in 14 patients: 7 with iron deficiency and 7 with raised serum iron levels. The decreased enzymatic activity in iron deficiency was confirmed. Plasma selenium was significantly lower in patients with lower serum iron; furthermore there is a significant correlation between serum iron and plasma selenium concentrations. Another correlation even more significant was found between plasma selenium and enzyme activity in all the cases we studied. These data suggests that the importance of iron for GSH-Px activity may be merely due to its relationship with selenium and that plasma selenium concentration may be of critical importance for enzyme activity. (author)

Selenium-containing indolyl compounds

DEFF Research Database (Denmark)

Casaril, Angela M; Ignasiak, Marta T; Chuang, Christine Y

2017-01-01

materials, including extracellular matrix (ECM) proteins, within the artery wall. Here we investigated the potential of selenium-containing indoles to afford protection against these oxidants, by determining rate constants (k) for their reaction, and quantifying the extent of damage on isolated ECM proteins......Tyr on HCAEC-ECM were also reduced. These data demonstrate that the novel selenium-containing compounds show high reactivity with oxidants and may modulate oxidative and nitrosative damage at sites of inflammation, contributing to a reduction in tissue dysfunction and atherogenesis....

Preparation and antioxidant properties of selenium nanoparticles-loaded chitosan microspheres

Directory of Open Access Journals (Sweden)

Bai K

2017-06-01

Full Text Available Kaikai Bai,1,2 Bihong Hong,1,2 Jianlin He,1,2 Zhuan Hong,1,2 Ran Tan1,2 1Third Institute of Oceanography, 2Engineering Research Center of Marine Biological Resource, Comprehensive Utilization, State Oceanic Administration, Xiamen, People’s Republic of China Abstract: Selenium nanoparticles (SeNPs, as a special form of selenium (Se supplement, have attracted worldwide attention due to their favorable properties and unique bioactivities. Herein, an eco-friendly and economic way to prepare stable SeNPs is introduced. SeNPs were synthesized in aqueous chitosan (CTS and then embedded into CTS microspheres by spray-drying, forming selenium nanoparticles-loaded chitosan microspheres (SeNPs-M. The physicochemical properties including morphology, elemental state, size distribution and surface potential were investigated. Institute of Cancer Research mice were used as model animal to evaluate the bioactivities of SeNPs-M. Trigonal-phase SeNPs of ~35 nm were synthesized, and SeNPs-M physically embedding those SeNPs were successfully prepared. Amazingly, acute toxicity test indicated that SeNPs-M were much safer than selenite in terms of Se dose, with a LD50 of around 18-fold of that of selenite. In addition, SeNPs-M possessed powerful antioxidant activities, as evidenced by a dramatic increase of both Se retention and the levels of glutathione peroxidase, superoxide dismutase and catalase. The design of SeNPs-M can offer a new way for further development of SeNPs with a higher efficacy and better biosafety. Thus, SeNPs-M may be a potential candidate for further evaluation as an Se supplement with antioxidant properties and be used against Se deficiency in animals and human beings. Keywords: selenium, nano, microsphere, chitosan, antioxidant

Effect of irradiation on sod activity and selenium content in garlic

International Nuclear Information System (INIS)

Xu Weimin; Zheng Anjian; Yan Jianmin; Cao Qingsui; Wu Haihong; Cao Shifeng

2006-01-01

The effects of irradiation at 0.1 kGy, 1.0 kGy on SOD activity and the content of total selenium, inorganic selenium, organic selenium in garlic (Allium sativum L.) stored at 10 degree C or 25 degree C were investigated. The results indicated that irradiation treatment with 0.1 kGy, 1 kGy significantly slowed the reduction of SOD activities in garlic stored at 10 degree C or 25 degree C, while the treatment irradiation had no influence on the content of all kinds of selenium. But the garlic stored at 25 degree C had higher content of total selenium, inorganic selenium, organic selenium than that in garlic stored at 10 degree C. (authors)

Exploring resource efficiency for energy, land and phosphorus use

NARCIS (Netherlands)

Berg, van den Maurits; Hermans, Kathleen; Vuuren, van Detlef P.; Bouwman, A.F.; Kram, Tom; Bakkes, Jan

2016-01-01

In this paper, we present four model-based scenarios exploring the potential for resource efficiency for energy, land and phosphorus use, and implications for resource depletion, climate change and biodiversity. The scenarios explored include technological improvements as well as structural

Thyroid hormones regulate selenoprotein expression and selenium status in mice.

Directory of Open Access Journals (Sweden)

Jens Mittag

Full Text Available Impaired expression of selenium-containing proteins leads to perturbed thyroid hormone (TH levels, indicating the central importance of selenium for TH homeostasis. Moreover, critically ill patients with declining serum selenium develop a syndrome of low circulating TH and a central downregulation of the hypothalamus-pituitary-thyroid axis. This prompted us to test the reciprocal effect, i.e., if TH status would also regulate selenoprotein expression and selenium levels. To investigate the TH dependency of selenium metabolism, we analyzed mice expressing a mutant TH receptor α1 (TRα1+m that confers a receptor-mediated hypothyroidism. Serum selenium was reduced in these animals, which was a direct consequence of the mutant TRα1 and not related to their metabolic alterations. Accordingly, hyperthyroidism, genetically caused by the inactivation of TRβ or by oral TH treatment of adult mice, increased serum selenium levels in TRα1+m and controls, thus demonstrating a novel and specific role for TRα1 in selenium metabolism. Furthermore, TH affected the mRNA levels for several enzymes involved in selenoprotein biosynthesis as well as serum selenoprotein P concentrations and the expression of other antioxidative selenoproteins. Taken together, our results show that TH positively affects the serum selenium status and regulates the expression of several selenoproteins. This demonstrates that selenium and TH metabolism are interconnected through a feed-forward regulation, which can in part explain the rapid parallel downregulation of both systems in critical illness.

Resource efficiency and culture--workplace training for small and medium-sized enterprises.

Science.gov (United States)

Bliesner, Anna; Liedtke, Christa; Rohn, Holger

2014-05-15

Although there are already some qualification offers available for enterprises to support resource efficiency innovations, the high potentials that can be identified especially for small and medium sized enterprises (SMEs) have not been activated until now. As successful change lies in the hands of humans, the main aim of vocational education has to be the promotion of organisational and cultural changes in the enterprises. As there is already a small but increasing number of enterprises that perform very well in resource efficiency innovations one question arises: What are typical characteristics of those enterprises? Leaning on a good-practice approach, the project "ResourceCulture" is going to prove or falsify the hypothesis that enterprises being successful with resource efficiency innovations have a specific culture of trust, which substantially contributes to innovation processes, or even initially enables them. Detailed empirical field research will light up which correlations between resource efficiency, innovation and cultures of trust can be found and will offer important aspects for the improvement of management instruments and qualification concepts for workplace training. The project seizes qualification needs that were likewise mentioned by enterprises and consultants, regarding the implementation of resource efficiency. This article - based on first empirical field research results - derives preliminary indications for the design of the qualification module for the target groups resource efficiency consultants and managers. On this basis and in order to implement "ResourceCulture" conceptual and methodological starting points for workplace training are outlined. Copyright © 2013 Elsevier B.V. All rights reserved.

EURRECA—Estimating Selenium Requirements for Deriving Dietary Reference Values

NARCIS (Netherlands)

Hurst, R.; Collings, R.; Harvey, L.J.; King, M.; Hooper, L.; Bouwman, J.; Gurinovic, M.; Fairweather-Tait, S.J.

2013-01-01

Current reference values for selenium, an essential micronutrient, are based on the intake of selenium that is required to achieve maximal glutathione peroxidase activity in plasma or erythrocytes. In order to assess the evidence of relevance to setting dietary reference values for selenium, the

Biorepository for Selenium and Vitamin E Cancer Prevention Trial (SELECT) | Division of Cancer Prevention

Science.gov (United States)

As the largest prostate cancer prevention trial ever undertaken, the Selenium and Vitamin E Cancer Prevention Trial (SELECT) has assembled a substantial biorepository of specimens. To help make SELECT resources available to a wider research community, NCI and the Southwest Oncology Group are developing a plan for prostate cancer biology and nutritional science and

Analyzing and Controlling the Efficiency of Use of the Enterprise’s Financial Resources

Directory of Open Access Journals (Sweden)

Nazarova Karina O.

2017-05-01

Full Text Available The article is aimed at analysis of the features of formation of the enterprise’s financial resources and proposal of an evaluation of efficiency as to their use. The relevance of the topic is based on the need to find a mechanism for evaluation of efficiency of the financial resources of enterprise. Ways of dealing with problems related to the use of financial resources were explored. Characteristic features of the financial resources of enterprises have been provided. The system of management of financial resources, as well as the management practices (traditional and progressive, have been reflected. It is known that a rational, economical use of available financial resources is necessary to improve the financial well-being of an enterprise. For this reason, the article focuses on the concept of «efficient use of financial resources». A generalizing indicator of the efficiency of use of the enterprise’s financial resources has been proposed.

Ecological Importance of Insects in Selenium Biogenic Cycling

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Nadezhda Golubkina

2014-01-01

Full Text Available Selenium is an essential trace element for animal and human beings. Despite the importance of insects in most ecosystems and their significant contribution to the biological cycling of trace elements due to high abundance, population productivity, and diverse ecosystem functions, surprisingly little information is available on selenium bioaccumulation by these arthropods. This review considers selenium essentiality and toxicity to insects as well as insects’ contribution to selenium trophic transfer through the food chains. Data on Se accumulation by insects of the Dniester River Valley with no anthropogenic Se loading reveal typically low Se content in necrophagous insects compared to predators and herbivores and seasonal variations in Se accumulation.

The Effect on Selenium Concentrations of a Randomized Intervention with Fish and Mussels in a Population with Relatively Low Habitual Dietary Selenium Intake

Science.gov (United States)

Outzen, Malene; Tjønneland, Anne; Larsen, Erik H.; Andersen, Klaus K.; Christensen, Jane; Overvad, Kim; Olsen, Anja

2015-01-01

Selenium status of the Danish population is below that assumed optimal for the suggested protective effects against chronic diseases, including certain cancers. Fish and shellfish are important dietary sources of selenium in Denmark. We investigated the effect of increased fish and mussel intake on selenium blood concentrations in a population with relatively low habitual dietary selenium intake. We randomly assigned 102 healthy men and women (all non-smokers) aged 48–76 years to an intervention group (n = 51) or a control group (n = 51). Intervention participants received 1000 g fish and mussels/week for 26 weeks (~50 μg selenium/day). Controls received no intervention. Non-fasting blood samples were taken and whole blood selenium was determined using inductively coupled plasma-mass spectrometry (ICP-MS), and plasma selenoprotein P (SelP) was determined by high performance liquid chromatography coupled to ICP-MS. All available observations were included in linear multiple regression analysis to evaluate the effect of the intervention. The difference in mean change for intervention compared with control persons was 14.9 ng/mL (95% CI: 10.2, 19.7) for whole blood selenium, and 7.0 ng/mL (95% CI: 3.1, 10.9) for plasma SelP (Weeks 0–26). Selenium concentrations were significantly increased after 26 weeks of intervention, albeit to a lower degree than expected. PMID:25599275

Comparing Profitability and Efficiency of Resource Use in Vegetable ...

African Journals Online (AJOL)

This study compared resource allocation, yield, net farm income and resource use efficiency under private and government controlled vegetable irrigation schemes. Production data covering three vegetable enterprises were collected from 280 respondents. This consisted of 141 from private and 139 from government ...

Sulfur, selenium, tellurium and polonium

International Nuclear Information System (INIS)

Berry, F.J.

1987-01-01

This chapter on the coordination compounds of sulfur, selenium, tellurium and polonium starts with an introduction to the bonding, valence and geometry of the elements. Complexes of the group VIB elements are discussed with particular reference to the halo and pseudohalide complexes, oxo acid complexes, oxygen and nitrogen donor complexes and sulfur and selenium donor complexes. There is a section on the biological properties of the complexes discussed. (UK)

Selenium, selenoproteins and the thyroid gland: interactions in health and disease.

Science.gov (United States)

Schomburg, Lutz

2011-10-18

The trace element selenium is an essential micronutrient that is required for the biosynthesis of selenocysteine-containing selenoproteins. Most of the known selenoproteins are expressed in the thyroid gland, including some with still unknown functions. Among the well-characterized selenoproteins are the iodothyronine deiodinases, glutathione peroxidases and thioredoxin reductases, enzymes involved in thyroid hormone metabolism, regulation of redox state and protection from oxidative damage. Selenium content in selenium-sensitive tissues such as the liver, kidney or muscle and expression of nonessential selenoproteins, such as the glutathione peroxidases GPx1 and GPx3, is controlled by nutritional supply. The thyroid gland is, however, largely independent from dietary selenium intake and thyroid selenoproteins are preferentially expressed. As a consequence, no explicit effects on thyroid hormone profiles are observed in healthy individuals undergoing selenium supplementation. However, low selenium status correlates with risk of goiter and multiple nodules in European women. Some clinical studies have demonstrated that selenium-deficient patients with autoimmune thyroid disease benefit from selenium supplementation, although the data are conflicting and many parameters must still be defined. The baseline selenium status of an individual could constitute the most important parameter modifying the outcome of selenium supplementation, which might primarily disrupt self-amplifying cycles of the endocrine-immune system interface rectifying the interaction of lymphocytes with thyroid autoantigens. Selenium deficiency is likely to constitute a risk factor for a feedforward derangement of the immune system-thyroid interaction, while selenium supplementation appears to dampen the self-amplifying nature of this derailed interaction.

Toenail mercury and dyslipidemia: Interaction with selenium.

Science.gov (United States)

Park, Kyong; Seo, Eunmin

2017-01-01

Although compelling evidences from in vivo and in vitro studies exist, limited studies have examined the association between chronic mercury exposure and dyslipidemia. Particularly, data are sparse regarding the influence of selenium on this association of mercury with dyslipidemia in humans. The purpose of the current study was to examine the associations of toenail mercury with dyslipidemia and its components, and to examine whether selenium in toenails modifies these associations. We performed cross-sectional analyses using baseline data from a cohort in the Yeungnam area in South Korea, including 232 men and 269 women. Toenail mercury and selenium concentrations were quantified using neutron activation analysis, and fasting serum lipid measurements were obtained through the medical examination. Odds ratios of the prevalent hypercholesterolemia, hyper-LDL-cholesterolemia, hypo-HDL-cholesterolemia, hypertriglyceridemia, and dyslipidemia in correlation with mercury levels were calculated using multivariable logistic regression. The mean levels of toenail mercury were 0.47μg/g for men and 0.34μg/g for women. After adjustment for multiple confounding variables, participants in the highest tertile of toenail mercury levels had 4.08 (95% CI 1.09-15.32, p for trend=0.02) times higher risk of hyper-LDL-cholesterolemia, and 2.24 (95% CI 1.15-4.37, p for trend=0.004) times higher risk of dyslipidemia than those in the lowest tertile. Selenium is a significant effect-modifier for these associations; the highest tertile of toenail mercury were significantly associated with a higher risk of hypercholesterolemia (OR 5.25, 95% CI 1.04-26.38) and dyslipidemia (OR 2.98, 95% CI 1.16-7.66) compared to the lowest tertile at toenail selenium levels ≤0.685μg/g, while these associations became weak and non-significant, showing OR 0.98 and 95% CI 0.25-3.80 for hypercholesterolemia and OR 1.99 and 95% CI 0.73-5.45 for dyslipidemia at toenail selenium levels >0.685μg/g. We

[Is plasma selenium correlated to transthyretin levels in critically ill patients?

Science.gov (United States)

Freitas, Renata G B O N; Nogueira, Roberto Jose Negrão; Cozzolino, Silvia Maria Franciscato; Vasques, Ana Carolina Junqueira; Ferreira, Matthew Thomas; Hessel, Gabriel

2017-06-05

Selenium is an essential trace element, but critically ill patients using total parenteral nutrition (PN) do not receive selenium because this mineral is not commonly offered. Threfore, the eval uation of plasma selenium levels is very important for treating or preventing this deficiency. Recent studies have shown that transthyretin may reflect the selenium intake and could be considered a biomarker. However, this issue is still little explored in the literature. This study aims to investigate the correlation of transthyretin with the plasma selenium of critically ill patients receiving PN. This was a prospective cohort study with 44 patients using PN without selenium. Blood samples were carried out in 3 stages: initial, 7th and 14th day of PN. In order to evaluate the clinical condition and the inflammatory process, albumin, C-reactive protein (CRP), transthyretin, creatinine and HDL cholesterol levels were observed. To assess the selenium status, plasma selenium and glutathione peroxidase (GPx) in whole blood were measured. Descriptive analyses were performed and the ANOVA, Mann-Whitney and Spearman's coefficient tests were conducted; we assumed a significance level of 5%. A positive correlation of selenium with the GPx levels (r = 0.46; p = 0.03) was identified. During two weeks, there was a positive correlation of transthyretin with plasma selenium (r = 0.71; p = 0.05) regardless of the CRP values. Transthyretin may have reflected plasma selenium, mainly because the correlation was verified after the acute phase.

Search for relevant indications for selenium supplementation in thyroid diseases.

Science.gov (United States)

Wojciechowska-Durczynska, Katarzyna; Lewinski, Andrzej

2017-08-01

Selenium plays a significant role in the thyroid function and its deficiency is considered by some authors to be a cause of thyroid disorders. The potential therapeutic influence of selenium supplementation in thyroid disease was investigated in several studies and some results were encouraging, however results were inconsistent and did not allow conclusion to be drawn. For that reason, we have performed a review study on relevance of selenium supplementation in thyroid disease. Till now, there is no strong evidence that selenium supplementation leads to clinical improvement in the course of autoimmune thyroiditis, nodular goitre or thyroid cancer. On the other hand, there is some evidence that selenium is effective in the treatment of orbitopathy; thus, the European Group on Graves' Orbitopathy (EUGOGO) recommends selenium administration in mild active orbitopathy.

Selenium Speciation and Management in Wet FGD Systems

Energy Technology Data Exchange (ETDEWEB)

Searcy, K; Richardson, M; Blythe, G; Wallschlaeger, D; Chu, P; Dene, C

2012-02-29

This report discusses results from bench- and pilot-scale simulation tests conducted to determine the factors that impact selenium speciation and phase partitioning in wet FGD systems. The selenium chemistry in wet FGD systems is highly complex and not completely understood, thus extrapolation and scale-up of these results may be uncertain. Control of operating parameters and application of scrubber additives have successfully demonstrated the avoidance or decrease of selenite oxidation at the bench and pilot scale. Ongoing efforts to improve sample handling methods for selenium speciation measurements are also discussed. Bench-scale scrubber tests explored the impacts of oxidation air rate, trace metals, scrubber additives, and natural limestone on selenium speciation in synthetic and field-generated full-scale FGD liquors. The presence and concentration of redox-active chemical species as well as the oxidation air rate contribute to the oxidation-reduction potential (ORP) conditions in FGD scrubbers. Selenite oxidation to the undesirable selenate form increases with increasing ORP conditions, and decreases with decreasing ORP conditions. Solid-phase manganese [Mn(IV)] appeared to be the significant metal impacting the oxidation of selenite to selenate. Scrubber additives were tested for their ability to inhibit selenite oxidation. Although dibasic acid and other scrubber additives showed promise in early clear liquor (sodium based and without calcium solids) bench-scale tests, these additives did not show strong inhibition of selenite oxidation in tests with higher manganese concentrations and with slurries from full-scale wet FGD systems. In bench-tests with field liquors, addition of ferric chloride at a 250:1 iron-to-selenium mass ratio sorbed all incoming selenite to the solid phase, although addition of ferric salts had no impact on native selenate that already existed in the field slurry liquor sample. As ORP increases, selenite may oxidize to selenate more

Protective effects of novel organic selenium compounds against oxidative stress in the nematode Caenorhabditis elegans

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Sílvio Terra Stefanello

2015-01-01

Full Text Available Organic selenium compounds possess numerous biological properties, including antioxidant activity. Yet, the high toxicity of some of them, such as diphenyl diselenide (DPDS, is a limiting factor in their current usage. Accordingly, we tested four novel organic selenium compounds in the non-parasite nematode Caenorhabditis elegans and compared their efficacy to DPDS. The novel organic selenium compounds are β-selenoamines 1-phenyl-3-(p-tolylselanylpropan-2-amine (C1 and 1-(2-methoxyphenylselanyl-3-phenylpropan-2-amine (C2 and analogs of DPDS 1,2-bis(2-methoxyphenyldiselenide (C3 and 1,2-bisp-tolyldiselenide (C4. Synchronized worms at the L4 larval stage were exposed for one hour in M9 buffer to these compounds. Oxidative stress conditions were induced by juglone (200 μM and heat shock (35 °C. Moreover, we evaluated C. elegans behavior, GST-4::GFP (glutathione S-transferase expression and the activity of acetylcholinesterase (AChE. All tested compounds efficiently restored viability in juglone stressed worms. However, DPDS, C2, C3 and C4 significantly decreased the defecation cycle time. Juglone-induced GST-4::GFP expression was not attenuated in worms pretreated with the novel compounds, except with C2. Finally, AChE activity was reduced by DPDS, C2, C3 and C4. To our knowledge, this is study firstly showed the effects of C1, C2, C3 and C4 selenium-derived compounds in C. elegans. Low toxic effects were noted, except for reduction in the defecation cycle, which is likely associated with AChE inhibition. The juglone-induced stress (reduced viability was fully reversed by compounds to control animal levels. C2 was also efficient in reducing the juglone-induced GST-4::GFP expression, suggesting the latter may mediate the stress induced by this compound. Future studies could be profitably directed at addressing additional molecular mechanisms that mediate the protective effects of these novel organic selenium compounds.

Enrichment of the African catfish Clarias gariepinus (Burchell) with functional selenium originating from garlic: effect of enrichment period and depuration on total selenium level and sensory properties

NARCIS (Netherlands)

Schram, E.; Schelvis-Smit, A.A.M.; Heul, van der J.W.; Luten, J.B.

2010-01-01

We wanted to optimize the procedure for the selenium enrichment of farmed African catfish, using garlic as dietary selenium source. In the first experiment we established the relation between the length of the selenium enrichment period and the resulting total selenium level in the fillet of the

Assessing global resource utilization efficiency in the industrial sector.

Science.gov (United States)

Rosen, Marc A

2013-09-01

Designing efficient energy systems, which also meet economic, environmental and other objectives and constraints, is a significant challenge. In a world with finite natural resources and large energy demands, it is important to understand not just actual efficiencies, but also limits to efficiency, as the latter identify margins for efficiency improvement. Energy analysis alone is inadequate, e.g., it yields energy efficiencies that do not provide limits to efficiency. To obtain meaningful and useful efficiencies for energy systems, and to clarify losses, exergy analysis is a beneficial and useful tool. Here, the global industrial sector and industries within it are assessed by using energy and exergy methods. The objective is to improve the understanding of the efficiency of global resource use in the industrial sector and, with this information, to facilitate the development, prioritization and ultimate implementation of rational improvement options. Global energy and exergy flow diagrams for the industrial sector are developed and overall efficiencies for the global industrial sector evaluated as 51% based on energy and 30% based on exergy. Consequently, exergy analysis indicates a less efficient picture of energy use in the global industrial sector than does energy analysis. A larger margin for improvement exists from an exergy perspective, compared to the overly optimistic margin indicated by energy. Copyright © 2012 Elsevier B.V. All rights reserved.

Conditions for a carrier multiplication in amorphous-selenium based photodetector

Energy Technology Data Exchange (ETDEWEB)

Masuzawa, Tomoaki; Kuniyoshi, Shingo; Onishi, Masanori; Kato, Richika; Saito, Ichitaro; Okano, Ken [Department of Material Science, International Christian University, S102 Science Hall, ICU, 3-10-2 Osawa, Mitaka, Tokyo 181-8585 (Japan); Yamada, Takatoshi [Nanotube Research Center, National Institute of Advanced Industrial Science and Technology (AIST), AIST Tsukuba Central 5, Tsukuba, Ibaraki 305-8568 (Japan); Koh, Angel T. T.; Chua, Daniel H. C. [Department of Materials Science and Engineering, National University of Singapore, 7 Engineering Drive 1, Singapore 117574 (Singapore); Shimosawa, Tatsuo [Department of Clinical Laboratory, Faculty of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyoku, Tokyo 113-8655 (Japan)

2013-02-18

Amorphous selenium is a promising candidate for high sensitivity photodetector due to its unique carrier multiplication phenomenon. More than 10 carriers can be generated per incident photon, which leads to high photo-conversion efficiency of 1000% that allows real-time imaging in dark ambient. However, application of this effect has been limited to specific devices due to the lack in material characterization. In this article, mechanism of carrier multiplication has been clarified using time-of-flight secondary ion mass spectroscopy and Raman spectroscopy. A prototype photodetector achieved photo conversion efficiency of 4000%, which explains the signal enhancement mechanism in a-Se based photodetector.

Conditions for a carrier multiplication in amorphous-selenium based photodetector

International Nuclear Information System (INIS)

Masuzawa, Tomoaki; Kuniyoshi, Shingo; Onishi, Masanori; Kato, Richika; Saito, Ichitaro; Okano, Ken; Yamada, Takatoshi; Koh, Angel T. T.; Chua, Daniel H. C.; Shimosawa, Tatsuo

2013-01-01

Amorphous selenium is a promising candidate for high sensitivity photodetector due to its unique carrier multiplication phenomenon. More than 10 carriers can be generated per incident photon, which leads to high photo-conversion efficiency of 1000% that allows real-time imaging in dark ambient. However, application of this effect has been limited to specific devices due to the lack in material characterization. In this article, mechanism of carrier multiplication has been clarified using time-of-flight secondary ion mass spectroscopy and Raman spectroscopy. A prototype photodetector achieved photo conversion efficiency of 4000%, which explains the signal enhancement mechanism in a-Se based photodetector.

Analyses of Selenotranscriptomes and Selenium Concentrations in Response to Dietary Selenium Deficiency and Age Reveal Common and Distinct Patterns by Tissue and Sex in Telomere-Dysfunctional Mice.

Science.gov (United States)

Cao, Lei; Zhang, Li; Zeng, Huawei; Wu, Ryan Ty; Wu, Tung-Lung; Cheng, Wen-Hsing

2017-10-01

Background: The hierarchies of tissue selenium distribution and selenotranscriptomes are thought to critically affect healthspan and longevity. Objective: We determined selenium status and selenotranscriptomes in response to long-term dietary selenium deficiency and age in tissues of male and female mice. Methods: Weanling telomerase RNA component knockout C57BL/6 mice were fed a selenium-deficient (0.03 mg Se/kg) Torula yeast-based AIN-93G diet or a diet supplemented with sodium selenate (0.15 mg Se/kg) until age 18 or 24 mo. Plasma, hearts, kidneys, livers, and testes were collected to assay for selenotranscriptomes, selected selenoproteins, and tissue selenium concentrations. Data were analyzed with the use of 2-factor ANOVA (diet × age) in both sexes. Results: Dietary selenium deficiency decreased ( P ≤ 0.05) selenium concentrations (65-72%) and glutathione peroxidase (GPX) 3 (82-94%) and selenoprotein P (SELENOP) (17-41%) levels in the plasma of both sexes of mice and mRNA levels (9-68%) of 4, 4, and 12 selenoproteins in the heart, kidney, and liver of males, respectively, and 5, 16, and 14 selenoproteins, respectively, in females. Age increased selenium concentrations and SELENOP levels (27% and 30%, respectively; P ≤ 0.05) in the plasma of males only but decreased (12-46%; P selenium deficiency and age in ≥1 tissue or sex, or both. Dietary selenium deficiency upregulated (40-160%; P ≤ 0.05) iodothyronine deiodinase 2 ( Dio2 ) and selenoprotein N ( Selenon ) in the kidneys of males. Age upregulated (11-44%; P selenium status and selenotranscriptomes because of dietary selenium deficiency and age. © 2017 American Society for Nutrition.

COMPARISON OF DETERMINING METHODS REGARDING SELENIUM CONTENT IN WHEAT PLANT

Directory of Open Access Journals (Sweden)

Mihaela Monica Stanciu-Burileanu

2010-01-01

Full Text Available As a metallic chemical element, selenium has received special attention from biologists because of its dual role as a trace element essential and toxic. The important part of enzymes that protect cells against the effects of free radicals that are produced during normal metabolism of oxygen. Also, selenium is essential for normal immune system and thyroid gland, The concentration of selenium in the soil, which varies by region, determines the default concentration of selenium in plants growing in the soil.The purpose of this paper is to present methods of comparison, dry oxidation at 450ºC and wet digestion – digestion with acids in high concentrations at microwave system digestion, for determining selenium content from wheat samples collected from the south-eastern part of Romania, namely Bărăgan Plain and Central-South Dobrogea. Selenium separation and dosage from obtained extracts carry out through a selective hydride generation atomic absorption spectrophotometry. With the software SURFER, a tendency map of selenium distribution was drawn.

Workshop Summary Proceedings Document: G7 Alliance on Resource Efficiency: U.S.-hosted Workshop on the Use of Life Cycle Concepts in Supply Chain Management to Achieve Resource Efficiency

Science.gov (United States)

This proceedings document summarizes prepared remarks, presentations and discussions from the G7 Alliance on Resource Efficiency: U.S.-hosted Workshop on the Use of Life Cycle Concepts in Supply Chain Management to Achieve Resource Efficiency.

Selenium and the thyroid: A close-knit connection

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Ashok K Bhuyan

2012-01-01

Full Text Available Introduction: In areas with severe selenium deficiency higher incidence of thyroiditis has been reported due to a decreased activity of selenium-dependent glutathione peroxidase enzyme within thyroid cells. Aims and Objective: To study the effect of selenium supplementation in patients with autoimmune thyroid disease. Materials and Methods: This is a blinded placebo-controlled prospective study done in 60 patients with autoimmune thyroid disease (as defined by an anti-thyroid peroxidase antibody (TPOAb level more than 150 IU/ml irrespective of the baseline thyroid status. Patients with overt hyperthyroidism who are on antithyroid drugs, patients on any other medication, which may alter the immunity status of the patients, and pregnant patients were excluded from the study. Patients were randomized into two age and TPOAb-matched groups; 30 patients received 200 μg of sodium selenite/day, orally, for 3 months, and 30 patients received placebo. All hypothyroid patients were given l-thyroxine replacement. Results: Of 30 patients in the selenium treated group, 6 patients were overtly hypothyroid, 15 were subclinical hypothyroid, 6 were euthyroid, and 3 were subclinical hyperthyroid. The mean TPOAb concentration decreased significantly by 49.5% (P < 0.013 in the selenium treated group versus 10.1% (P < 0.95 in the placebo-treated group. Conclusion: Selenium substitution has a significant impact on inflammatory activity in thyroid-specific autoimmune disease. It would be of interest to determine whether early treatment with selenium in patients with newly developed autoimmune thyroiditis may delay or even prevent the natural course of these diseases.

Resource efficiency in agricultural development: human capital ...

African Journals Online (AJOL)

Resource efficiency in agricultural development: human capital development perspective and poverty challenges in developing countries. ... in Nigeria and contributed about 23.9% of the Gross National Domestic product in 2016. ... Equally, the new focus on agriculture involves training on new technologies and evolving ...

Labour productivity and resource use efficiency amongst ...

African Journals Online (AJOL)

The study examined labour productivity and resource efficiency amongst smallholder cocoa farmers in Abia State, Nigeria. A purposive random sampling technique was adopted in selecting 60 cocoa farmers from three agricultural zones in the State. The analytical techniques used involve inferential statistics like means, ...

A pilot study of the selenium content in the soils of the endemic Dobrogea region, Romania, using nuclear and related analytical techniques

International Nuclear Information System (INIS)

Tripadus, V.; Craciun, L.; Lacatusu, R.; Frontasyeva, M.V.; Stan, O.; Lyapunov, S.M.

2000-01-01

At present, there is growing interest in the understanding of the role of selenium in human and animal metabolism. Selenium is known to be a normal component of several enzymes, proteins and some aminoacrylic transfer nucleic acids. Low levels of selenium intake are reported to cause diseases such as cardiomyopathy (Keshan disease), cancer and endemic osteoarthropathy characterized by necrosis of cartilage and dystrophy of skeletal muscles (Kaschin-Beck disease). In conjunction with the vitamin E, it removes free radicals from the living organisms. About two-to-three orders of magnitude higher levels of selenium are known to impart toxic effects. The Dobrogea Region in Romania is known for endemic cardiovascular diseases affecting domestic cattle, mostly sheep and milk cows. Soil, being the source of selenium, is responsible for its content in the whole trophic chain. A limited number of soil samples collected in the pastures (Dobrogea) were subject to epithermal neutron activation analysis at the IBR-2 pulsed fast reactor in Dubna, Russia. To verify the obtained results, the same samples were analyzed by the fluorescent extraction method, especially efficient for determination of selenium at low concentrations, at the Geological Institute of RAS in Moscow, Russia. The mean concentration of selenium was found to be equal to 0.38 ppm with a standard deviation of 0.13. The accuracy of the selenium determination was not worse than 20%. These preliminary results are not evidence of obvious selenium deficiency, however. A systematic study on a large geographical scale is strongly recommended to elucidate the problem of cattle morbidity in the examined area. (authors)

Recent trends in selenium regulation and management

International Nuclear Information System (INIS)

Sobolewski, A.

2010-01-01

Selenium is a contaminant encountered at uranium mines. When discharged into water, it can build up in the food chain and become toxic to egg-laying fish and shorebirds. This presentation reviews recent developments in its regulation, management and treatment. Selenium will soon be regulated on the basis of its concentration in fish or bird eggs, not its dissolved concentrations, which challenges managers trying to establish acceptable discharge limits. Information supporting this change will be discussed. Recent developments to manage and treat selenium will also be reviewed, emphasizing new chemical and biological treatment processes applicable at uranium mines and mill sites. (author)

Learning selenium testing tools with Python

CERN Document Server

Gundecha, Unmesh

2014-01-01

If you are a quality testing professional, or a software or web application developer looking to create automation test scripts for your web applications, with an interest in Python, then this is the perfect guide for you. Python developers who need to do Selenium testing need not learn Java, as they can directly use Selenium for testing with this book.

Comparison between selenium and tellurium clusters

International Nuclear Information System (INIS)

Benamar, A.; Rayane, D.; Tribollet, B.; Broyer, M.; Melinon, P.

1991-01-01

Selenium and tellurium clusters are produced by the inert gas condensation technique. The mass spectra of both species are completely different and reveal different properties. In selenium, a periodicity of 6-7 is observed and may be interpreted by the binding energy between small cyclic molecules. Moreover, it was very difficult to obtained large clusters probably because the binding energy between these molecules is very small. In tellurium, these periodic structures do not exist and large clusters are easily obtained in nucleation conditions where only small selenium clusters are present. These results are discussed and a simple nucleation model is used to illustrate this different behavior. Finally these clusters properties are correlated to the bulk structure of both materials. (orig.)

Selenium Accumulating Leafy Vegetables Are a Potential Source of Functional Foods

Directory of Open Access Journals (Sweden)

Petro E. Mabeyo

2015-01-01

Full Text Available Selenium deficiency in humans has been associated with various diseases, the risks of which can be reduced through dietary supplementation. Selenium accumulating plants may provide a beneficial nutrient for avoiding such illnesses. Thus, leafy vegetables such as Amaranthus hybridus, Amaranthus sp., Cucurbita maxima, Ipomoea batatas, Solanum villosum, Solanum scabrum, and Vigna unguiculata were explored for their capabilities to accumulate selenium when grown on selenium enriched soil and for use as a potential source of selenium enriched functional foods. Their selenium contents were determined by spectrophotometry using the complex of 3,3′-diaminobenzidine hydrochloride (DABH as a chromogen. The mean concentrations in the leaves were found to range from 7.90±0.40 to 1.95±0.12 μg/g dry weight (DW, with C. maxima accumulating the most selenium. In stems, the accumulated selenium content ranged from 1.12±0.10 μg/g in Amaranthus sp. to 5.35±0.78 μg/g DW in C. maxima and was hence significantly different (P<0.01. The cancer cell line MDA-MB-231 was used in cytotoxicity assays to determine the anticancer potential of these extracts. With exception of S. scabrum and S. villosum, no cytotoxicity was detected for the selenium enriched vegetable extracts up to 100 μg/mL concentration. Hence, following careful evaluation the studied vegetables may be considered as selenium enriched functional foods.

The necessity of selenium substitution in total parenteral nutrition and artificial alimentation.

Science.gov (United States)

Gramm, H J; Kopf, A; Brätter, P

1995-03-01

For the trace element selenium, in contrast to zinc, iron, copper, chromium, manganese and iodine, there is still no clear official recommendation with regard to routine substitution in artificial nutrition. An overview of the manifestations of selenium deficiency in humans during the period 1979-1995 shows that nutritive deficiencies are exclusively TPN-induced or the result of severe malnutrition. The pathology of TPN-induced selenium deficiency and the analytic assessment of selenium status are described. Patients undergoing long-term parenteral nutrition or suffering from an increased loss of intestinal secretions have to be characterized as being especially at risk for clinical selenium deficiency. The relationship of the serum selenium kinetics in pediatric and adult patients to the depletion of body compartments during the course of short-term and prolonged TPN is discussed. Because of the importance of the selenoproteins, the regularly occurring depletion during selenium-free TPN and the borderline supply of selenium in Germany the routine substitution of selenium in TPN is strongly recommended. The pharmaceutical industry should be encouraged to develop a trace element solution that includes selenium, so that the nutritive requirement of patients on TPN can be satisfied. Adequate intravenous dosage recommendations are based on maintenance of glutathione peroxidase homeostasis. The routine supplementation dosage may not meet the selenium requirements of intensive care patients under conditions of increased metabolic demands on their anti-oxidative system.

Selenium supplementation for patients with Graves’ hyperthyroidism (the GRASS trial)

DEFF Research Database (Denmark)

Watt, Torquil; Cramon, Per; Bjorner, Jakob Bue

2013-01-01

Graves' hyperthyroidism is an autoimmune disease causing hyperfunction of the thyroid gland. The concentration of selenium is high in the thyroid gland and two important groups of enzymes within the thyroid are selenoproteins, that is, they depend on selenium. Selenium may have beneficial effects...

Energy efficiency resource modeling in generation expansion planning

International Nuclear Information System (INIS)

Ghaderi, A.; Parsa Moghaddam, M.; Sheikh-El-Eslami, M.K.

2014-01-01

Energy efficiency plays an important role in mitigating energy security risks and emission problems. In this paper, energy efficiency resources are modeled as efficiency power plants (EPP) to evaluate their impacts on generation expansion planning (GEP). The supply curve of EPP is proposed using the production function of electricity consumption. A decision making framework is also presented to include EPP in GEP problem from an investor's point of view. The revenue of EPP investor is obtained from energy cost reduction of consumers and does not earn any income from electricity market. In each stage of GEP, a bi-level model for operation problem is suggested: the upper-level represents profit maximization of EPP investor and the lower-level corresponds to maximize the social welfare. To solve the bi-level problem, a fixed-point iteration algorithm is used known as diagonalization method. Energy efficiency feed-in tariff is investigated as a regulatory support scheme to encourage the investor. Results pertaining to a case study are simulated and discussed. - Highlights: • An economic model for energy efficiency programs is presented. • A framework is provided to model energy efficiency resources in GEP problem. • FIT is investigated as a regulatory support scheme to encourage the EPP investor. • The capacity expansion is delayed and reduced with considering EPP in GEP. • FIT-II can more effectively increase the energy saving compared to FIT-I

UV-photochemical vapor generation of selenium for atomic absorption spectrometry: Optimization and 75Se radiotracer efficiency study

Czech Academy of Sciences Publication Activity Database

Rybínová, M.; Musil, Stanislav; Červený, J.; Vobecký, Miloslav; Rychlovský, P.

2016-01-01

Roč. 123, SEP (2016), s. 134-142 ISSN 0584-8547 R&D Projects: GA ČR GA14-23532S Institutional support: RVO:68081715 Keywords : UV-photochemical vapor generation * Selenium * 75Se radiotracer Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 3.241, year: 2016

Effects of organic selenium in broiler feed on the content of selenium and fatty acid profile in lipids of thigh muscle tissue

Directory of Open Access Journals (Sweden)

Zlata Kralik

2013-01-01

Full Text Available The aim of our study was to determine the effects of selenium supplementation to broiler feed on the content of selenium, total fatty acids in lipids and on the oxidative stability of broiler thigh muscle tissue. The experiment involved 40 broilers fattened for 42 days. During the first three weeks, all broilers consumed starter diet containing 22% crude protein. After three weeks, broilers were divided into two groups and fed finisher diets containing 18% crude protein and supplemented with 3% sunflower oil and 3% linseed oil. Group 1 was not administered artificial selenium; Group 2 was supplemented with organic selenium at the amount of 0.5 mg Se/kg of feed. Significantly higher (P P P > 0.05 and increase of linolenic acid and total n-3 polyunsaturated fatty acids (P < 0.05 in thigh muscle tissue of broilers. Since selenium and n-3 polyunsaturated fatty acids are nutricines, our results show that the produced broiler meat may be considered as functional food.

Optimization of Selenium-enriched Candida utilis by Response Surface Methodology

Directory of Open Access Journals (Sweden)

ZHANG Fan

2014-12-01

Full Text Available The fermentation conditions of selenium enrichment by Candida utilis were studied. Based on the results of the single factor experiment, three factors including the concentration of sodium selenite, inital pH and incubation temperature were selected. The response surface method was used to optimize the various factors. The optimal conditions were obtained as follows: incubation time was 30 h, time of adding selenium was mid-logarithmic, the sodium selenite concentration was 35 mg·L-1 with inital pH of 6.6, incubation concentration of 10%, incubation temperature of 27 ℃, the medium volume of 150 mL/500 mL, respectively. Under the optimal condition, the biomass was 6.87 g·L-1. The total selenium content of Candida utilis was 12 639.7 μg·L-1, and the selenium content of the cells was 1 839.8 μg·g-1, in which sodium selenite conversion rate was 79.1% and the organic selenium was higher than 90%. The actual value of selenium content was substantially consistent with the theoretical value, and the response surface methodology was applicable for the fermentation conditions of selenium enriched by Candida utilis.

JV Task 96 - Phase 2 - Investigating the Importance of the Mercury-Selenium Interaction

Energy Technology Data Exchange (ETDEWEB)

Nicholas Ralston; Laura Raymond

2008-03-01

In order to improve the understanding of the mercury issue, it is vital to study mercury's effects on selenium physiology. While mercury present in the environment or food sources may pose health risks, the protective effects of selenium have not been adequately considered in establishing regulatory policy. Numerous studies report that vulnerability to mercury toxicity is inversely proportional to selenium status or level. However, selenium status has not been considered in the development of the reference dosage levels for mercury exposure. Experimental animals fed low-selenium diets are far more vulnerable to mercury toxicity than animals fed normal selenium, and animals fed selenium-rich diets are even more resistant. Selenium-dependent enzymes in brain and endocrine tissues can be impaired by excessive mercury exposure, apparently because mercury has an extremely high binding affinity for selenium. When selenium becomes bound to mercury, it is unable to participate in the metabolic cycling of selenoprotein synthesis. Because of mercury-dependent impairments of selenoprotein synthesis, various antioxidant and regulatory functions in brain biochemistry are compromised. This report details a 2-year multiclient-funded research program designed to examine the interactions between mercury and selenium in animal models. The studies explored the effects of dietary intakes of toxic amounts of methylmercury and the protective effects of the normal dietary range of selenium in counteracting mercury toxicity. This study finds that the amounts of selenium present in ocean fish are sufficient to protect against far larger quantities of methylmercury than those present in typical seafoods. Toxic effects of methylmercury exposure were not directly proportional to mercury concentrations in blood, brain, or any other tissues. Instead, mercury toxicity was proportional to molar ratios of mercury relative to selenium. In order to accurately assess risk associated with

Selenium toxicity: cause and effects in aquatic birds

Science.gov (United States)

Spallholz, J.E.; Hoffman, D.J.

2002-01-01

There are several manners in which selenium may express its toxicity: (1) an important mechanism appears to involve the formation of CH3Se- which either enters a redox cycle and generates superoxide and oxidative stress, or forms free radicals that bind to and inhibit important enzymes and proteins. (2) Excess selenium as selenocysteine results in inhibition of selenium methylation metabolism. As a consequence, concentrations of hydrogen selenide, an intermediate metabolite, accumulate in animals and are hepatotoxic, possibly causing other selenium-related adverse effects. (3) It is also possible that the presence of excess selenium analogs of sulfur-containing enzymes and structural proteins play a role in avian teratogenesis. l-selenomethionine is the most likely major dietary form of selenium encountered by aquatic birds, with lesser amounts of l-selenocysteine ingested from aquatic animal foods. The literature is suggestive that l-selenomethionine is not any more toxic to adult birds than other animals. l-Selenomethionine accumulates in tissue protein of adult birds and in the protein of egg white as would be expected to occur in animals. There is no suggestion from the literature that the levels of l-selenomethionine that would be expected to accumulate in eggs in the absence of environmental concentration of selenium pose harm to the developing embryo. For several species of aquatic birds, levels of Se as selenomethionine in the egg above 3 ppm on a wet weight basis result in reduced hatchability and deformed embryos. The toxicity of l-selenomethionine injected directly into eggs is greater than that found from the entry of l-selenomethionine into the egg from the normal adult diet. This suggests that there is unusual if not abnormal metabolism of l-selenomethionine in the embryo not seen when l-selenomethionine is present in egg white protein where it likely serves as a source of selenium for glutathione peroxidase synthesis in the developing aquatic chick.

Advancing Resource Efficiency in the Supply Chain - Observations and Opportunities for Action

Science.gov (United States)

This document provides U.S. EPA’s perspectives on the discussions at the G7 Alliance on Resource Efficiency U.S.-hosted Workshop on the Use of Life Cycle Concepts in Supply Chain Management to Achieve Resource Efficiency that was held March 22-23, 2016.

Selenium accumulation in plants--phytotechnological applications and ecological implications.

Science.gov (United States)

Valdez Barillas, José Rodolfo; Quinn, Colin F; Pilon-Smits, Elizabeth A H

2011-01-01

Selenium (Se) is an essential trace element for many organisms including humans, yet toxic at higher levels. Both Se deficiency and toxicity are problems worldwide. Since plants readily accumulate and volatilize Se, they may be used both as a source of dietary Se and for removing excess Se from the environment. Plant species differ in their capacity to metabolize and accumulate Se, from non-Se accumulators ( 1,000 mg Se/kg DW). Here we review plant mechanisms of Se metabolism in these various plant types. We also summarize results from genetic engineering that have led to enhanced plant Se accumulation, volatilization, and/or tolerance, including field studies. Before using Se-accumulating plants at a large scale we need to evaluate the ecological implications. Research so far indicates that plant Se accumulation significantly affects the plant's ecological interactions below and above ground. Selenium canprotect plants from fungal pathogens and from a variety of invertebrate and vertebrate herbivores, due to both deterrence and toxicity. However, specialist (Se-tolerant herbivores), detritivores and endophytes appear to utilize Se hyperaccumulator plants as a resource. These findings are relevant for managing phytoremediation of Se and similar elements.

Food chain model to predict westslope cutthroat trout ovary selenium concentrations from water concentrations in the Elk Valley, BC

International Nuclear Information System (INIS)

Orr, P.; Wiramanaden, C.; Franklin, W.; Fraser, C.

2010-01-01

The 5 coal mines operated by Teck Coal Ltd. in British Columbia's Elk River watershed release selenium during weathering of mine waste rock. Since 1966, several field studies have been conducted in which selenium concentrations in biota were measured. They revealed that tissue concentrations are higher in aquatic biota sampled in lentic compared to lotic habitats of the watershed with similar water selenium concentrations. Two food chain models were developed based on the available data. The models described dietary selenium accumulation in the ovaries of lotic versus lentic westslope cutthroat trout (WCT), a valued aquatic resource in the Elk River system. The following 3 trophic transfer relationships were characterized for each model: (1) water to base of the food web, (2) base of the food web to benthic invertebrates, and (3) benthic invertebrates to WCT ovaries. The lotic and lentic models combined the resulting equations for each trophic transfer relationships to predict WCT ovary concentrations from water concentrations. The models were in very good agreement with the available data, despite fish movement and the fact that composite benthic invertebrate sample data were only an approximation of the feeding preferences of individual fish. Based on the observed rates of increase in water selenium concentrations throughout the watershed, the models predicted very small/slow increases in WCT ovary concentrations with time.

The curative and antioxidative efficiency of ivermectin and ivermectin + vitamin E-selenium treatment on canine Sarcoptes scabiei infestation.

Science.gov (United States)

Behera, Suvendu Kumar; Dimri, Umesh; Singh, Shanker Kumar; Mohanta, Ranjan Kumar

2011-04-01

The objective of the present study was to investigate the curative and antioxidative efficacy of ivermectin and ivermectin + vitamin E-selenium, and the influence of these agents on oxidative stress parameters in canines infested by Sarcoptes scabiei. Twenty two sarcoptic mites infested dogs and nine healthy dogs of 6 months to 2 years of age were divided into three groups. Group I comprised of healthy dogs (n=9) whereas animals in group II (n=11) and III (n=11) were positive for scabies. Group II animals were treated with only 1% ivermectin @ 0.2 mg/kg SC whereas group III were additionally treated with Vitamin E and selenium (tocopherol 50 mg + Se 1.5 mg/ml) @ 0.5 ml/20 kg IM at weekly intervals for three times. Blood samples were collected on day 0 and 28 post therapy. The values for hemato-biochemical parameters and activities of antioxidant enzymes were significantly decreased (Pdogs in comparison to the healthy dogs on day 0 which approached normalcy by day 28 post therapy. The dogs of group III showed better clinical recovery in comparison to group II at the end of therapy. Thus, administration of vitamin E and selenium in addition to standard therapy can alleviate these alterations hastening the clinical recovery of diseased dogs and can be recommended as an adjunct therapy with miticides for canine sarcoptic mange. © Springer Science+Business Media B.V. 2011

Research on Evaluation of resource allocation efficiency of transportation system based on DEA

Science.gov (United States)

Zhang, Zhehui; Du, Linan

2017-06-01

In this paper, we select the time series data onto 1985-2015 years, construct the land (shoreline) resources, capital and labor as inputs. The index system of the output is freight volume and passenger volume, we use Quantitative analysis based on DEA method evaluated the resource allocation efficiency of railway, highway, water transport and civil aviation in China. Research shows that the resource allocation efficiency of various modes of transport has obvious difference, and the impact on scale efficiency is more significant. The most important two ways to optimize the allocation of resources to improve the efficiency of the combination of various modes of transport is promoting the co-ordination of various modes of transport and constructing integrated transportation system.

Dietary Selenium in Adjuvant Therapy of Viral and Bacterial Infections12

Science.gov (United States)

Steinbrenner, Holger; Al-Quraishy, Saleh; Dkhil, Mohamed A; Wunderlich, Frank; Sies, Helmut

2015-01-01

Viral and bacterial infections are often associated with deficiencies in macronutrients and micronutrients, including the essential trace element selenium. In selenium deficiency, benign strains of Coxsackie and influenza viruses can mutate to highly pathogenic strains. Dietary supplementation to provide adequate or supranutritional selenium supply has been proposed to confer health benefits for patients suffering from some viral diseases, most notably with respect to HIV and influenza A virus (IAV) infections. In addition, selenium-containing multimicronutrient supplements improved several clinical and lifestyle variables in patients coinfected with HIV and Mycobacterium tuberculosis. Selenium status may affect the function of cells of both adaptive and innate immunity. Supranutritional selenium promotes proliferation and favors differentiation of naive CD4-positive T lymphocytes toward T helper 1 cells, thus supporting the acute cellular immune response, whereas excessive activation of the immune system and ensuing host tissue damage are counteracted through directing macrophages toward the M2 phenotype. This review provides an up-to-date overview on selenium in infectious diseases caused by viruses (e.g., HIV, IAV, hepatitis C virus, poliovirus, West Nile virus) and bacteria (e.g., M. tuberculosis, Helicobacter pylori). Data from epidemiologic studies and intervention trials, with selenium alone or in combination with other micronutrients, and animal experiments are discussed against the background of dietary selenium requirements to alter immune functions. PMID:25593145

Rethinking mercury: the role of selenium in the pathophysiology of mercury toxicity.

Science.gov (United States)

Spiller, Henry A

2018-05-01

There is increasing evidence that the pathophysiological target of mercury is in fact selenium, rather than the covalent binding of mercury to sulfur in the body's ubiquitous sulfhydryl groups. The role of selenium in mercury poisoning is multifaceted, bidirectional, and central to understanding the target organ toxicity of mercury. An initial search was performed using Medline/PubMed, Toxline, Google Scholar, and Google for published work on mercury and selenium. These searches yielded 2018 citations. Publications that did not evaluate selenium status or evaluated environmental status (e.g., lake or ocean sediment) were excluded, leaving approximately 500 citations. This initial selection was scrutinized carefully and 117 of the most relevant and representative references were selected for use in this review. Binding of mercury to thiol/sulfhydryl groups: Mercury has a lower affinity for thiol groups and higher affinity for selenium containing groups by several orders of magnitude, allowing for binding in a multifaceted way. The established binding of mercury to thiol moieties appears to primarily involve the transport across membranes, tissue distribution, and enhanced excretion, but does not explain the oxidative stress, calcium dyshomeostasis, or specific organ injury seen with mercury. Effects of mercury on selenium and the role this plays in the pathophysiology of mercury toxicity: Mercury impairs control of intracellular redox homeostasis with subsequent increased intracellular oxidative stress. Recent work has provided convincing evidence that the primary cellular targets are the selenoproteins of the thioredoxin system (thioredoxin reductase 1 and thioredoxin reductase 2) and the glutathione-glutaredoxin system (glutathione peroxidase). Mercury binds to the selenium site on these proteins and permanently inhibits their function, disrupting the intracellular redox environment. A number of other important possible target selenoproteins have been identified

Reduced selenium-binding protein 1 in breast cancer correlates with poor survival and resistance to the anti-proliferative effects of selenium.

Directory of Open Access Journals (Sweden)

Sheng Zhang

Full Text Available Supplemental dietary selenium is associated with reduced incidence of many cancers. The antitumor function of selenium is thought to be mediated through selenium-binding protein 1 (SELENBP1. However, the significance of SELENBP1 expression in breast cancer is still largely unknown. A total of 95 normal and tumor tissues assay and 12 breast cancer cell lines were used in this study. We found that SELENBP1 expression in breast cancer tissues is reduced compared to normal control. Low SELENBP1 expression in ER(+ breast cancer patients was significantly associated with poor survival (p<0.01, and SELENBP1 levels progressively decreased with advancing clinical stages of breast cancer. 17-β estradiol (E2 treatment of high SELENBP1-expressing ER(+ cell lines led to a down-regulation of SELENBP1, a result that did not occur in ER(- cell lines. However, after ectopic expression of ER in an originally ER(- cell line, down-regulation of SELENBP1 upon E2 treatment was observed. In addition, selenium treatment resulted in reduced cell proliferation in endogenous SELENBP1 high cells; however, after knocking-down SELENBP1, we observed no significant reduction in cell proliferation. Similarly, selenium has no effect on inhibition of cell proliferation in low endogenous SELENBP1 cells, but the inhibitory effect is regained following ectopic SELENBP1 expression. Furthermore, E2 treatment of an ER silenced high endogenous SELENBP1 expressing cell line showed no abolishment of cell proliferation inhibition upon selenium treatment. These data indicate that SELENBP1 expression is regulated via estrogen and that the cell proliferation inhibition effect of selenium treatment is dependent on the high level of SELENBP1 expression. Therefore, the expression level of SELENBP1 could be an important marker for predicting survival and effectiveness of selenium supplementation in breast cancer. This is the first study to reveal the importance of monitoring SELENBP1 expression

Biofortification and phytoremediation of selenium in China

Directory of Open Access Journals (Sweden)

Zhilin eWu

2015-03-01

Full Text Available Selenium (Se is an essential trace element for humans and animals but at high concentrations, Se becomes toxic to organisms due to Se replacing sulfur in proteins. Selenium biofortification is an agricultural process that increases the accumulation of Se in crops, through plant breeding, genetic engineering, or use of Se fertilizers. While Se phytoremediation is a green biotechnology to clean up Se-contaminated environments, primarily through phytoextraction and phytovolatilization. By integrating Se phytoremediation and biofortification technologies, Se-enriched plant materials harvested from Se phytoremediation can be used as Se-enriched green manures or other supplementary sources of Se for producing Se-biofortified agricultural products. Earlier studies primarily aimed at enhancing efficacy of phytoremediation and biofortification of Se based on natural variation in progenitor or identification of unique plant species. In this review, we discuss promising approaches to improve biofortification and phytoremediation of Se using knowledge acquired from model crops. We also explored the feasibility of applying biotechnologies such as inoculation of microbial strains for improving the efficiency of biofortification and phytoremediation of Se. The key research and practical challenges that remain in improving biofortification and phytoremediation of Se have been highlighted, and the future development and uses of Se-biofortified agricultural products in China has also been discussed.

Improving resource-use efficiency in rice-based systems of Pakistan

NARCIS (Netherlands)

Awan, M.I.

2013-01-01

Keywords: Aerobic rice, water productivity, pre-flowering phenology, eco-efficiency, perceptions, transformational technology, food security, resource constraints, Punjab, Pakistan.

Just like in many other parts of the world, diminishing resources of water, labour and energy

Influence of dietary sodium selenite on tissue selenium levels of growing pigs

International Nuclear Information System (INIS)

Moksnes, K.; Tollersrud, S.; Larsen, H.J.

1982-01-01

Twenty Norwegian Landrace pigs were divided into 5 groups and fed a basal diet consisting of a mixture of dried skim milk and whey powder together with ground barley. The diet was supplemented with 0, 0.2, 0.8, 1.2, and 2.2 μg/g selenium as sodium selenite and was fed for 12 weeks. The muscle selenium level was increased by a factor of about 4 and the liver selenium by a factor of about 12 when the dietary selenium supplement was increased from zero to 2.2μg/g. There was a significant linear correlation between dietary selenium and selenium concentrations in tissues. Possible benefit for humans consuming meat from animals having received the selenium doses used in this experiment are discussed. (author)

Low selenium and reduced cognitive function in a cohort elderly study

Institute of Scientific and Technical Information of China (English)

Jianchao Bian; Sujuan Gao; Qiliang Qin; Zhongjie Yun; Yuan Liu; Shuliang Song; Chuanjiao Liu; Xiaohong Luo; Jie Gao; Chaoke Liang

2010-01-01

Cognitive function in the elderly is affected by various environmental,social,and individual factors.Studies show that chemical trace elements are closely related to cognitive function.As a protective factor,selenium promotes cognition in the elderly.However,study results into the effects of selenium on cognition have varied.By eliminating unstable environmental and other related factors,the present study selected elderly individuals from rural areas of the Shandong province to verify whether low selenium exposure is a risk factor for decreased cognitive function.Results demonstrated that age,sex,education,occupation,hypertension,stroke,and body selenium levels were factors affecting cognitive function in the elderly,and that selenium was an important protective factor.Moreover,results supported the hypothesis that a lifelong low selenium level is associated with low cognitive function.

Selenium as an essential micronutrient: roles in cell cycle and apoptosis.

Science.gov (United States)

Zeng, Huawei

2009-03-23

Selenium is an essential trace element for humans and animals, and selenium deficiency is associated with several disease conditions such as immune impairment. In addition, selenium intakes that are greater than the recommended daily allowance (RDA) appear to protect against certain types of cancers. In humans and animals, cell proliferation and death must be regulated to maintain tissue homeostasis, and it has been well documented that numerous human diseases are directly related to the control of cell cycle progression and apoptosis. Thus, the elucidation of the mechanisms by which selenium regulates the cell cycle and apoptosis can lead to a better understanding of the nature of selenium's essentiality and its role in disease prevention. This article reviews the status of knowledge concerning the effect of selenium on cell cycle and apoptosis.

Power efficient dynamic resource scheduling algorithms for LTE

OpenAIRE

Han, C; Beh, KC; Nicolaou, M; Armour, SMD; Doufexi, A

2010-01-01

This paper presents a link level analysis of the rate and energy efficiency performance of the LTE downlink considering the unitary codebook based precoding scheme. In a multi-user environment, appropriate radio resource management strategies can be applied to the system to improve the performance gain by exploiting multi-user diversity in the time, frequency and space domains and the gains can be translated to energy reduction at the base station. Several existing and novel resource scheduli...

Assessing global resource utilization efficiency in the industrial sector

International Nuclear Information System (INIS)

Rosen, Marc A.

2013-01-01

Designing efficient energy systems, which also meet economic, environmental and other objectives and constraints, is a significant challenge. In a world with finite natural resources and large energy demands, it is important to understand not just actual efficiencies, but also limits to efficiency, as the latter identify margins for efficiency improvement. Energy analysis alone is inadequate, e.g., it yields energy efficiencies that do not provide limits to efficiency. To obtain meaningful and useful efficiencies for energy systems, and to clarify losses, exergy analysis is a beneficial and useful tool. Here, the global industrial sector and industries within it are assessed by using energy and exergy methods. The objective is to improve the understanding of the efficiency of global resource use in the industrial sector and, with this information, to facilitate the development, prioritization and ultimate implementation of rational improvement options. Global energy and exergy flow diagrams for the industrial sector are developed and overall efficiencies for the global industrial sector evaluated as 51% based on energy and 30% based on exergy. Consequently, exergy analysis indicates a less efficient picture of energy use in the global industrial sector than does energy analysis. A larger margin for improvement exists from an exergy perspective, compared to the overly optimistic margin indicated by energy. - Highlights: ► The global industrial sector and its industries are assessed by using energy and exergy methods. ► Global industrial sector efficiencies are evaluated as 51% based on energy and 30% based on exergy. ► Exergy analysis shows global industrial energy to be less efficient than does energy analysis. ► A misleadingly low margin for efficiency improvement is indicated by energy analysis. ► A significant and rational margin for efficiency improvement exists from an exergy perspective

Selenium intake and metabolic syndrome: A systematic review.

Science.gov (United States)

Retondario, Anabelle; Fernandes, Ricardo; Rockenbach, Gabriele; Alves, Mariane de Almeida; Bricarello, Liliana Paula; Trindade, Erasmo Benicio Santos de Moraes; Vasconcelos, Francisco de Assis Guedes de

2018-03-02

Metabolic syndrome is a multi-causal disease. Its treatment includes lifestyle changes with a focus on weight loss. This systematic review assessed the association between Selenium intake and metabolic syndrome. Data were collected mainly from four databases: PubMed, CENTRAL (Cochrane), Scopus and Web of Knowledge. Keywords related to metabolic syndrome, selenium, as well as metabolic syndrome features were searched. This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Statement. A systematic review protocol was registered at PROSPERO (n. 42016046321). Two reviewers independently screened 2957 abstracts. Six studies were included to perform data extraction with standardized spreadsheets. The risk of bias was assessed by using specific tools according to the design of the relevant studies. An assessment was carried out based on the appropriateness of the study reports accordingly to STROBE and the CONSORT-based checklist for each study design. Three studies found no association between Selenium intake and metabolic syndrome; two of them found an inverse association; and one study found a direct association between Selenium intake and metabolic syndrome. One study also showed an inverse association between Selenium intake and the prevalence of high waist circumference, high diastolic blood pressure, and hyperglycaemia in women. Overall, based on the argumentation and results of this study, it is possible to conclude that Selenium intake and metabolic syndrome are not clearly associated in adults and elderly. Copyright © 2018 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

Activation analysis of selenium in odorous vegetable foods

International Nuclear Information System (INIS)

Suzuki, Shogo; Hirai, Shoji; Noda, Katsuhiko.

1981-01-01

The selenium in odorous vegetables was analyzed by nondestructive neutron activation analysis using 75 Se, by the γ-ray coincidence method with a Ge(Li) and a NaI(Tl) detectors of definite energy ranges. By means of the coincidence counting, the background spectrum in 75 Se in the vicinity of 265 KeV was able to be reduced to about 1/20 of that by the former detector alone, so that the 75 Se detection sensitivity was raised over fourfold. Thus the selenium in odorous vegetables was able to be determined down to the content as low as 0.02 μg/g. The selenium content in garlic bulbs was 0.02 - 0.31 μg/g, and in onion bulbs 0.02 - 0.05 μg/g, both of which agreed well with those by fluorometry. In other odorous vegetables, the selenium content was as little as 0.1 μg/g or lower. It has been said that the selenium content is relatively large along with sulfur because of the same group, but it was found to be fairly small in the odorous vegetables. (Mori, K.)

[Plasma selenium and peripartum cardiomyopathy in Bamako, Mali].

Science.gov (United States)

Cénac, A; Touré, K; Diarra, M B; Sergeant, C; Jobic, Y; Sanogo, K; Dembele, M; Fayol, V; Simonoff, M

2004-01-01

Peripartum heart failure due to unexplained dilated cardiomyopathy is a common disorder as Savannak-Sahelian Africa. One of the many suspected risk factors identified is selenium deficiency. The purpose of this study was to measure plasma selenium levels in patients with peripartum heart failure due to cardiomyopathy in Bamako, Republic of Mali and compare data with healthy Sahalian women with the same obstetrical status. Plasma selenium was measured in a patient group consisting of 28 Malian women presenting peripartum heart failure and in a control group of 28 healthy breast-feeding Nigerien women of comparable age. The criteria for matching the two groups was parity (similar number of deliveries) since multiparity is a risk factor for peripartum cardiomyopathy. The Wilcoxon test (nonparametric) was used to compare the 2 groups considering up value < 0.05 as significant. Plasma selenium was significantly lower in patients from Mali than in controls from Niger (65 +/- 17 ng/ml vs. 78 +/- 17 ng/ml, p = 0.01). The results of this study showing lower plasma selenium in Bamako patients with peripartum cardiomyopathy than in a matching healthy control population confirms the previous data from the Niamey study.

Selenium biofortification

Science.gov (United States)

Plant foods are the major dietary sources of selenium (Se) in most countries around the world, followed by meats and seafood. For this reason, it is vital to increase Se uptake by plants and to produce crops with higher Se concentrations and bioavailability in their edible tissues. One of the most p...

Evaluation of health resource utilization efficiency in community health centers of Jiangsu Province, China.

Science.gov (United States)

Xu, Xinglong; Zhou, Lulin; Antwi, Henry Asante; Chen, Xi

2018-02-20

While the demand for health services keep escalating at the grass roots or rural areas of China, a substantial portion of healthcare resources remain stagnant in the more developed cities and this has entrenched health inequity in many parts of China. At its conception, China's Deepen Medical Reform started in 2012 was intended to flush out possible disparities and promote a more equitable and efficient distribution of healthcare resources. Nearly half a decade of this reform, there are uncertainties as to whether the attainment of the objectives of the reform is in sight. Using a hybrid of panel data analysis and an augmented data envelopment analysis (DEA), we model human resources, material, finance to determine their technical and scale efficiency to comprehensively evaluate the transverse and longitudinal allocation efficiency of community health resources in Jiangsu Province. We observed that the Deepen Medical Reform in China has led to an increase concern to ensure efficient allocation of community health resources by health policy makers in the province. This has led to greater efficiency in health resource allocation in Jiangsu in general but serious regional or municipal disparities still exist. Using the DEA model, we note that the output from the Community Health Centers does not commensurate with the substantial resources (human resources, materials, and financial) invested in them. We further observe that the case is worst in less-developed Northern parts of Jiangsu Province. The government of Jiangsu Province could improve the efficiency of health resource allocation by improving the community health service system, rationalizing the allocation of health personnel, optimizing the allocation of material resources, and enhancing the level of health of financial resource allocation.

Selenium and Lung Cancer: A Systematic Review and Meta Analysis

Science.gov (United States)

Fritz, Heidi; Kennedy, Deborah; Fergusson, Dean; Fernandes, Rochelle; Cooley, Kieran; Seely, Andrew; Sagar, Stephen; Wong, Raimond; Seely, Dugald

2011-01-01

Background Selenium is a natural health product widely used in the treatment and prevention of lung cancers, but large chemoprevention trials have yielded conflicting results. We conducted a systematic review of selenium for lung cancers, and assessed potential interactions with conventional therapies. Methods and Findings Two independent reviewers searched six databases from inception to March 2009 for evidence pertaining to the safety and efficacy of selenium for lung cancers. Pubmed and EMBASE were searched to October 2009 for evidence on interactions with chemo- or radiation-therapy. In the efficacy analysis there were nine reports of five RCTs and two biomarker-based studies, 29 reports of 26 observational studies, and 41 preclinical studies. Fifteen human studies, one case report, and 36 preclinical studies were included in the interactions analysis. Based on available evidence, there appears to be a different chemopreventive effect dependent on baseline selenium status, such that selenium supplementation may reduce risk of lung cancers in populations with lower baseline selenium status (serumselenium (≥121.6 ng/mL). Pooling data from two trials yielded no impact to odds of lung cancer, OR 0.93 (95% confidence interval 0.61–1.43); other cancers that were the primary endpoints of these trials, OR 1.51 (95%CI 0.70–3.24); and all-cause-death, OR 0.93 (95%CI 0.79–1.10). In the treatment of lung cancers, selenium may reduce cisplatin-induced nephrotoxicity and side effects associated with radiation therapy. Conclusions Selenium may be effective for lung cancer prevention among individuals with lower selenium status, but at present should not be used as a general strategy for lung cancer prevention. Although promising, more evidence on the ability of selenium to reduce cisplatin and radiation therapy toxicity is required to ensure that therapeutic efficacy is maintained before any broad clinical recommendations can be made in this context. PMID:22073154

Mixed Surfactant Template Method for Preparation of Nanometer Selenium

Directory of Open Access Journals (Sweden)

Zhi-Lin Li

2009-01-01

Full Text Available Selenium nanoparticles have been synthesized in an aqueous solution by using sodium dodecyl sulfate and polyvinyl alcohol as a soft template. The factors on synthesis, such as reaction time, concentration of reactants and ultrasonic irradiation were studied. The uniform stable selenium nanospheres were obstained in the conditions of 1.0 (mass fraction sodium dodecyl sulfate, 1.0 (mass fraction polyvinyl alcohol, n(Vc:n(H2SeO3=7:1 and 7 minutes after the initiation of the reaction at room temperature. The average particle size of selenium is about 30 nm. The product was characterized by UV and TEM. Finally the applications of the red element nanometer selenium in anti-older cosmetics are presented.

Compact and resource efficient cities? Synergies and trade-offs in European cities

DEFF Research Database (Denmark)

Fertner, Christian; Große, Juliane

2016-01-01

city. Compact cities and compact urban development are thought to decrease energy and resource demand per capita and increase efficiency. At the same time trade-offs and potential rebound effects of increased resource efficiency question certain achievements of a dense urban structure. This paper...... alternative travel modes. Also the allocation of efficiency gains due to compact urban development has to be taken into account in order to avoid direct and indirect rebound effects....

The expression of selenium-binding protein 1 is decreased in uterine leiomyoma

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Quddus M Ruhul

2010-12-01

Full Text Available Abstract Background Selenium has been shown to inhibit cancer development and growth through the mediation of selenium-binding proteins. Decreased expression of selenium-binding protein 1 has been reported in cancers of the prostate, stomach, colon, and lungs. No information, however, is available concerning the roles of selenium-binding protein 1 in uterine leiomyoma. Methods Using Western Blot analysis and immunohistochemistry, we examined the expression of selenium-binding protein 1 in uterine leiomyoma and normal myometrium in 20 patients who had undergone hysterectomy for uterine leiomyoma. Results and Discussion The patient age ranged from 34 to 58 years with a mean of 44.3 years. Proliferative endometrium was seen in 8 patients, secretory endometrium in 7 patients, and atrophic endometrium in 5 patients. Two patients showed solitary leiomyoma, and eighteen patients revealed 2 to 5 tumors. Tumor size ranged from 1 to 15.5 cm with a mean of 4.3 cm. Both Western Blot analysis and immunohistochemistry showed a significant lower level of selenium-binding protein 1 in leiomyoma than in normal myometrium. Larger tumors had a tendency to show a lower level of selenium-binding protein 1 than smaller ones, but the difference did not reach a statistical significance. The expression of selenium-binding protein 1 was the same among patients with proliferative, secretory, and atrophic endometrium in either leiomyoma or normal myometrium. Also, we did not find a difference of selenium-binding protein 1 level between patients younger than 45 years and older patients in either leiomyoma or normal myometrium. Conclusions Decreased expression of selenium-binding protein 1 in uterine leiomyoma may indicate a role of the protein in tumorigenesis. Our findings may provide a basis for future studies concerning the molecular mechanisms of selenium-binding protein 1 in tumorigenesis as well as the possible use of selenium in prevention and treatment of uterine

HORMONAL REGULATION OF SELENIUM ACCUMULATION BY PLANTS

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N. A. Golubkina

2015-01-01

Full Text Available Hormonal regulation is considered to be a unique mechanism controlling growth and development of living organism. The review discusses the correlations between pant hormonal status of non-accumulators and hyper-accumulators of Se with the accumulation levels of this microelement. The phenomenon of stimulation and redistribution of selenium as a result of phytohormone treatment, the peculiarities of phytohormones effect among different species and cultivars, and influence of plant sexualization on selenium accumulation are described in article. Data of hormonal regulation of selenium level for spinach, garlic, perennial onion, Brassica chinenesis and Valeriana officialis are presented in the review.

Assessment of dissolved-selenium concentrations and loads in the lower Gunnison River Basin, Colorado, as part of the Selenium Management Program, from 2011 to 2016

Science.gov (United States)

Henneberg, Mark F.

2018-04-23

The Gunnison Basin Selenium Management Program implemented a water-quality monitoring network in 2011 in the lower Gunnison River Basin in Colorado. Selenium is a trace element that bioaccumulates in aquatic food chains and can cause reproductive failure, deformities, and other harmful effects. This report presents the percentile values of selenium because regulatory agencies in Colorado make decisions based on the U.S. Environmental Protection Agency (EPA) Clean Water Act Section 303(d) that uses percentile values of concentration. Also presented are dissolved-selenium loads at 18 sites in the lower Gunnison River Basin for water years (WYs) 2011–2016 (October 1, 2010, through September 30, 2016). Annual dissolved-selenium loads were calculated for five sites with continuous U.S. Geological Survey (USGS) streamflow-gaging stations. Annual dissolved-selenium loads for WY 2011 through WY 2016 ranged from 179 and 391 pounds (lb) at Uncompahgre River at Colona to 11,100 and 17,300 lb at Gunnison River near Grand Junction (herein called Whitewater), respectively. Instantaneous loads were calculated for five sites with continuous U.S. Geological Survey (USGS) streamflow-gaging stations and 13 ancillary sites where discrete water-quality sampling also took place, using discrete water-quality samples and the associated discharge measurements collected during the period. Median instantaneous loads ranged from 0.01 pound per day (lb/d) at Smith Fork near Lazear to 33.0 lb/d at Whitewater. Mean instantaneous loads ranged from 0.06 lb/d at Smith Fork near Lazear to 36.2 lb/d at Whitewater. Most tributary sites in the basin had a median instantaneous dissolved-selenium load of less than 20.0 lb/day. In general, dissolved-selenium loads at Gunnison River main-stem sites showed an increase from upstream to downstream. The State of Colorado water-quality standard for dissolved selenium of 4.6 micrograms per liter (µg/L) was compared to the 85th percentiles for dissolved

Natural resource windfalls and efficiency of local government expenditures: evidence from Peru

OpenAIRE

Ardanaz, Martin; Maldonado, Stanislao

2013-01-01

We study the role of natural resource windfalls in explaining the efficiency of public expenditures. Using a rich dataset of expenditures and public good provision for 1,836 municipalities in Peru for period 2001-2010, we estimate a non-monotonic relationship between the efficiency of public good provision and the level of natural resource transfers. Local governments that were extremely favored by the boom of mineral prices were more efficient in using fiscal windfalls whereas those benefite...

Sorption mechanisms of selenium species (selenite and selenate) on copper-based minerals

International Nuclear Information System (INIS)

Devoy, J.

2001-09-01

The sorption of radionuclides on the surface of minerals represents a process capable to delay the migration of the elements from a spent fuel deep repository towards the biosphere. In the framework of a deep underground repository, an engineered clay barrier has a high trapping capacity for cationic radio-elements, in particular because of the negative charge of clay surfaces. However, anionic radioelements like selenium species, would be only weakly retained by chemical processes. In order to optimize the trapping capacity of a clay barrier with respect to anionic species, prospective studies are carried out in order to find and evaluate some minerals with specific chemical trapping functions. Among radionuclides, the case of selenium has to be considered because its isotope 79 Se is present in radioactive wastes and has a half life time of 6.5 10 4 years. It is also judicious to find a mineral capable of trapping simultaneously several anionic radio-elements. Copper oxides and sulfides (Cu 2 O, CuO, Cu 2 S, CuS, CuFeS 2 and Cu 5 FeS 4 ) are good adsorbents with respect to selenium species (selenite and selenate). These minerals, with their selenium retention properties, could be used also for the decontamination of soils and waters or to process industrial effluents. The sorption mechanisms have been studied in details for copper oxides (Cu 2 O and CuO) with respect to selenite and selenate. Chalcomenite precipitates in acid pH conditions when selenite is added to a Cu 2 O and CuO suspension. Selenate, in contact with cuprite (Cu 2 O) leads also to a selenium-based precipitate in acid pH environment. For higher pH values, selenite and selenate are adsorbed on copper oxides (Cu 2 O and CuO) and lead to internal and external sphere complexes, respectively. In the case of a selenite/cuprite mixture in basic pH environment and at the equilibrium, a chemical reaction occurs between the oxidation product of cuprite, Cu(OH) 2 and HSeO 3 . A preliminary study of

Attractor neural networks with resource-efficient synaptic connectivity

Science.gov (United States)

Pehlevan, Cengiz; Sengupta, Anirvan

Memories are thought to be stored in the attractor states of recurrent neural networks. Here we explore how resource constraints interplay with memory storage function to shape synaptic connectivity of attractor networks. We propose that given a set of memories, in the form of population activity patterns, the neural circuit choses a synaptic connectivity configuration that minimizes a resource usage cost. We argue that the total synaptic weight (l1-norm) in the network measures the resource cost because synaptic weight is correlated with synaptic volume, which is a limited resource, and is proportional to neurotransmitter release and post-synaptic current, both of which cost energy. Using numerical simulations and replica theory, we characterize optimal connectivity profiles in resource-efficient attractor networks. Our theory explains several experimental observations on cortical connectivity profiles, 1) connectivity is sparse, because synapses are costly, 2) bidirectional connections are overrepresented and 3) are stronger, because attractor states need strong recurrence.

Determination of selenium status using the nail biologic monitor in a canine model

International Nuclear Information System (INIS)

Steven Morris, J.; Spate, V.L.; Ruth Ann Ngwenyama; Waters, D.J.

2012-01-01

Toenails and fingernails are routinely used to estimate selenium status in epidemiological studies; however, literature validating nail selenium concentration as a surrogate for critical organs is limited. In this study diets of intact male dogs were selenium supplemented at two physiological levels (3 and 6 μg/kg/day) in two different forms, selenomethionine and selenium-enriched bioformed yeast. The selenium-adequate basal diet consumed by the treatment and control groups during the 4-week run-in period and throughout the trial contained 0.3 ppm selenium. After 7 months the dogs in the two treatment groups and the control group were euthanized. Representative tissue samples from prostate, brain, liver, heart and skeletal muscle were collected, rinsed and frozen. Toenail clippings from multiple toes were also collected. Selenium was determined by neutron activation analysis using Se77m (half life = 17.4 s) at the University of Missouri Research Reactor Center. NIST SRM 1577, Bovine Liver was analyzed as a quality control. The analysts were blinded to control and treatment group assignments. As expected, tissue selenium levels increased proportionally with supplementation. A slightly greater increase in tissue selenium was observed for the purified selenomethionine compared to the bioformed yeast; however this trend was significant only for brain tissue. Toenail selenium concentrations and tissue selenium were highly correlated (p < 0.003) with Pearson coefficients of 0.759 (skeletal muscle), 0.745 (heart), 0.729 (brain), 0.723 (prostate), and 0.632 (liver). The toenail biologic monitor accurately assesses selenium status in skeletal muscle, heart, brain, prostate, and liver in the canine model. (author)

Supplementation of Merino ewes with vitamin E plus selenium increases α-tocopherol and selenium concentrations in plasma of the lamb but does not improve their immune function.

Science.gov (United States)

Sterndale, S; Broomfield, S; Currie, A; Hancock, S; Kearney, G A; Lei, J; Liu, S; Lockwood, A; Scanlan, V; Smith, G; Thompson, A N

2018-05-01

Vitamin E and selenium have been reported to improve immune function across a range of species. Ewes lambing on poor-quality dry pasture in autumn in Western Australia are at risk of being deficient in vitamin E and selenium at lambing thus predisposing their lambs to deficiencies and increasing the risk of infection and disease. This study tested the hypotheses that (i) supplementation of autumn-lambing ewes with vitamin E plus selenium in late gestation will increase the concentrations of vitamin E and selenium in plasma in the ewe and lamb and (ii) that the increased concentrations of vitamin E and selenium in plasma in the lambs will improve their innate and adaptive immune responses and thus survival. Pregnant Merino ewes were divided into a control group (n=58) which received no supplementation or a group supplemented with vitamin E plus selenium (n=55). On days 111, 125 and 140 of pregnancy ewes in the vitamin E plus selenium group were given 4 g all-rac-α-tocopherol acetate orally. On day 111 the ewes were also given 60 mg of selenium as barium selenate by subcutaneous injection. The concentrations of α-tocopherol and selenium were measured in ewes and/or lambs from day 111 of pregnancy to 14 weeks of age±10 days (weaning). Immune function of the lamb was assessed by analysing the numbers and phagocytic capacities of monocytes and polymorphonuclear leucocytes and plasma IgG and anti-tetanus toxoid antibody concentrations between birth and 14 weeks of age±10 days. Maternal supplementation with vitamin E plus selenium increased the concentration of α-tocopherol in plasma (1.13 v. 0.67 mg/l; P<0.001) and selenium in whole blood (0.12 v. 0.07 mg/l; P<0.01) of the ewes at lambing compared with controls. Supplementation also increased the concentration of α-tocopherol (0.14 v. 0.08 mg/l; P<0.001) and selenium (0.08 v. 0.05 mg/l; P<0.01) in lambs at birth compared with controls. There was no significant effect of supplementation on immune function or

Serum selenium levels and the risk of progression of laryngeal cancer.

Science.gov (United States)

Lubiński, Jan; Marciniak, Wojciech; Muszynska, Magdalena; Jaworowska, Ewa; Sulikowski, Mieczyslaw; Jakubowska, Anna; Kaczmarek, Katarzyna; Sukiennicki, Grzegorz; Falco, Michal; Baszuk, Piotr; Mojsiewicz, Magdalena; Kotsopoulos, Joanne; Sun, Ping; Narod, Steven A; Lubiński, Jan A

2018-01-01

Observational studies have reported an inverse relationship between selenium status (blood or toenail) and the risk of laryngeal cancer; however, the impact of low serum selenium level on survival has not been evaluated. We conducted a prospective study of 296 patients diagnosed with laryngeal cancer in Szczecin, Poland. Serum selenium was measured at diagnosis and prior to treatment. Patients were followed from the date of diagnosis to death at five years. Vital status was obtained by linkage to the Polish National Death Registry. The five-year survival after diagnosis was 82.0% (95% CI: 68% to 91%) for individuals in the highest quartile of serum selenium (> 66.8 μg/L) and was 28.6% (95% CI 19% to 42%) for individuals in the lowest quartile (selenium, compared to those in the highest quartile. The corresponding multivariate HR was 3.07 (95% CI 1.59 to 5.94). This study suggests that a selenium level in excess of 70 μg/L is associated with improved outcome among patients undergoing treatment for laryngeal cancer. Further studies are needed to evaluate if selenium supplementation to achieve this level might improve overall prognosis.

Modeling efficient resource allocation patterns for arable crop ...

African Journals Online (AJOL)

optimum plans. This should be complemented with strong financial support, farm advisory services and adequate supply of modern inputs at fairly competitive prices would enhance the prospects of the small holder farmers. Keywords: efficient, resource allocation, optimization, linear programming, gross margin ...

Selenium content of tissues in Finnish infants and adults with various diseases, and studies on the effects of selenium supplementation in neuronal ceroid lipofuscinosis patients

International Nuclear Information System (INIS)

Westermarck, T.

1977-01-01

A low blood selenium level has previously been observed in healthy inhabitants of Finland. In this study even lower blood selenium values were observed in patients with acrodermatitis enteropathica, dystrophia musculorum progressiva (Duchenne), infantile and juvenile type of neuronal ceroid lipofuscinosis (NCL), severe mental retardation caused by various factors, and myocardial infarction. The selenium content of the brain, heart, kidney and liver in patients of different ages was also determined. The highest selenium level was found in the kidney. The mean liver selenium concentrations in stillborn, premature and full-term neonates were 1.11 plus minus 0.23 (8), 1.21 plus minus 0.17 (12) and 0.93 plus minus 0.16 μg/g dry weight (12) respectively (the number of subjects in parentheses). The selenium values are considerably higher than those in infants of from one to nine months of age and adults, whose liver selenium values were 0.58 plus minus 0.21 (8) and 0.67 plus minus 0.08 μg/g dry weight (8) respectively. The vitamin E levels of serum in patients with NCL, as well as in subjects with severe mental retardation (controls), were low compared with values in healthy normal subjects. Sodium selenite supplementation in patients with NCL produced at least a transitory improvement without causing any toxic effects during one year of administration. (author)

The Thermodynamics of Selenium Minerals in Near-Surface Environments

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Vladimir Krivovichev

2017-10-01

Full Text Available Selenium compounds are relatively rare as minerals; there are presently only 118 known mineral species. This work is intended to codify and systematize the data of mineral systems and the thermodynamics of selenium minerals, which are unstable (selenides or formed in near-surface environments (selenites, where the behavior of selenium is controlled by variations of the redox potential and the acidity of solutions at low temperatures and pressures. These parameters determine the migration of selenium and its precipitation as various solid phases. All selenium minerals are divided into four groups—native selenium, oxide, selenides, and oxysalts—anhydrous selenites (I and hydrous selenites and selenates (II. Within each of the groups, minerals are codified according to the minimum number of independent elements necessary to define the composition of the mineral system. Eh–pH diagrams were calculated and plotted using the Geochemist’s Workbench (GMB 9.0 software package. The Eh–pH diagrams of the Me–Se–H2O systems (where Me = Co, Ni, Fe, Cu, Pb, Zn, Cd, Hg, Ag, Bi, As, Sb, Al and Ca were plotted for the average contents of these elements in acidic waters in the oxidation zones of sulfide deposits. The possibility of the formation of Zn, Cd, Ag and Hg selenites under natural oxidation conditions in near surface environments is discussed.

Distribution coefficients of caesium, chlorine, iodine, niobium, selenium and technetium on Olkiluoto soils

International Nuclear Information System (INIS)

Soederlund, M.; Lusa, M.; Virtanen, S.; Vaelimaa, I.; Hakanen, M.; Lehto, J.; Lahdenperae, A.-M.

2014-02-01

Retention of caesium, chlorine, iodine, niobium, selenium and technetium was investigated on soil samples from Olkiluoto using laboratory batch sorption experiments. Distribution coefficients were measured for both dried and sieved and untreated (wet, not sieved) mineral soil and humus in aerobic and anaerobic conditions. Mineralogical composition of the samples was determined by XRD-analysis. Caesium was sorbed efficiently on mineral soil samples and less efficiently on humus. Sorption decreased with decreasing cation exchange capacity and clay fraction content. The effect of competing cations decreased in the order Cs + >NH 4 + >K + >Ca 2+ >Na + . Chlorine was not retained by mineral soil samples, and the sorption was weak on humus. The sorption of iodine was the strongest on humus and the weakest on the untreated mineral soil samples in the anaerobic conditions. In the mineral soil samples, the sorption decreased with decreasing organic matter content and increasing pH. The retention of niobium on soil samples was the most efficient among the studied elements. The retention was high regardless of the aeration conditions. Sorption on humus was smaller. Selenium was retained efficiently on humus. Sorption on mineral soil samples was stronger in aerobic conditions. Sorption increased with time. Technetium was sorbed well on humus and anaerobic, untreated mineral soil samples. Sorption increased with increasing organic matter content and decreasing redox potential. The results from the sorption experiments are used in the site specific radionuclide migration modelling. (orig.)

Evaluation of the inorganic selenium biotransformation in selenium-enriched yogurt by HPLC-ICP-MS.

Science.gov (United States)

Alzate, Adriana; Cañas, Benito; Pérez-Munguía, Sandra; Hernández-Mendoza, Hector; Pérez-Conde, Concepción; Gutiérrez, Ana Maria; Cámara, Carmen

2007-11-28

Selenium is an essential element in the human diet. Interestingly, there has been an increased consumption of dietary supplements containing this element in the form of either inorganic or organic compounds. The effect of using selenium as a dietary supplement in yogurt has been evaluated. For this purpose, different concentrations of inorganic Se (ranging from 0.2 to 5000 microg g(-1)) have been added to milk before the fermentation process. Biotransformation of inorganic Se into organic species has been carefully evaluated by ion-exchange, reversed-phase, or size-exclusion chromatography, coupled to inductively coupled plasma mass spectrometry (ICP-MS). Yogurt fermentation in the presence of up to 2 microg g(-1) of Se(IV) produces a complete incorporation of this element into proteins as has been demonstrated applying a dialysis procedure. Analysis by SEC-ICP-MS showed that most of them have a molecular mass in the range of 30-70 kDa. Species determination after enzymatic hydrolysis has allowed the identification of Se-cystine using two different chromatographic systems. The biotransformation process that takes place during yogurt fermentation is very attractive because yogurt can act as a source of selenium supplementation.

Selenium transformation in coal mine spoils: Its environmental impact assessment

Energy Technology Data Exchange (ETDEWEB)

Harness, J.; Atalay, A.; Koll, K.J.; Zhang, H.; Maggon, D.

1991-12-31

The objective of this program was to conduct an environmental impact assessment study for selenium from coal mine spoils. The use of in-situ lysimetry to predict selenium speciation, transformation, and mobility under natural conditions was evaluated. The scope of the study was to construct and test field-scale lysimeter and laboratory mini-column to assess mobility and speciation of selenium in coal mine overburden and soil systems; to conduct soil and groundwater sampling throughout the state of Oklahoma for an overall environmental impact assessment of selenium; and to conduct an in-depth literature review on the solubility, speciation, mobility, and toxicity of selenium from various sources. Groundwater and surface soil samples were also collected from each county in Oklahoma. Data collected from the lysimeter study indicated that selenium in the overburden of the abandoned mine site was mainly found in the selenite form. The amount of selenite found was too low and immobile to be of concern to the environment. The spoil had equilibrated long enough (over 50 years) that most of the soluble forms of selenium have already been lost. Examination of the overburden indicated the presence of pyrite crystals that precipitated over time. The laboratory mini-column study indicated that selenite is quite immobile and remained on the overburden material even after leaching with dilute acid. Data from groundwater samples indicated that based on the current permissible level for selenium in groundwater (0.01 mg Se/L), Oklahoma groundwater is widely contaminated with the element. However, according to the new regulation (0.05 mg Se/L), which is to be promulgated in 1992, only 9 of the 77 counties in the state exceed the limit.

Bioaccumulation and toxicity of selenium compounds in the green alga Scenedesmus quadricauda

Science.gov (United States)

Umysová, Dáša; Vítová, Milada; Doušková, Irena; Bišová, Kateřina; Hlavová, Monika; Čížková, Mária; Machát, Jiří; Doucha, Jiří; Zachleder, Vilém

2009-01-01

Background Selenium is a trace element performing important biological functions in many organisms including humans. It usually affects organisms in a strictly dosage-dependent manner being essential at low and toxic at higher concentrations. The impact of selenium on mammalian and land plant cells has been quite extensively studied. Information about algal cells is rare despite of the fact that they could produce selenium enriched biomass for biotechnology purposes. Results We studied the impact of selenium compounds on the green chlorococcal alga Scenedesmus quadricauda. Both the dose and chemical forms of Se were critical factors in the cellular response. Se toxicity increased in cultures grown under sulfur deficient conditions. We selected three strains of Scenedesmus quadricauda specifically resistant to high concentrations of inorganic selenium added as selenite (Na2SeO3) – strain SeIV, selenate (Na2SeO4) – strain SeVI or both – strain SeIV+VI. The total amount of Se and selenomethionine in biomass increased with increasing concentration of Se in the culturing media. The selenomethionine made up 30–40% of the total Se in biomass. In both the wild type and Se-resistant strains, the activity of thioredoxin reductase, increased rapidly in the presence of the form of selenium for which the given algal strain was not resistant. Conclusion The selenium effect on the green alga Scenedesmus quadricauda was not only dose dependent, but the chemical form of the element was also crucial. With sulfur deficiency, the selenium toxicity increases, indicating interference of Se with sulfur metabolism. The amount of selenium and SeMet in algal biomass was dependent on both the type of compound and its dose. The activity of thioredoxin reductase was affected by selenium treatment in dose-dependent and toxic-dependent manner. The findings implied that the increase in TR activity in algal cells was a stress response to selenium cytotoxicity. Our study provides a new

Bioaccumulation and toxicity of selenium compounds in the green alga Scenedesmus quadricauda

Directory of Open Access Journals (Sweden)

Doucha Jiří

2009-05-01

Full Text Available Abstract Background Selenium is a trace element performing important biological functions in many organisms including humans. It usually affects organisms in a strictly dosage-dependent manner being essential at low and toxic at higher concentrations. The impact of selenium on mammalian and land plant cells has been quite extensively studied. Information about algal cells is rare despite of the fact that they could produce selenium enriched biomass for biotechnology purposes. Results We studied the impact of selenium compounds on the green chlorococcal alga Scenedesmus quadricauda. Both the dose and chemical forms of Se were critical factors in the cellular response. Se toxicity increased in cultures grown under sulfur deficient conditions. We selected three strains of Scenedesmus quadricauda specifically resistant to high concentrations of inorganic selenium added as selenite (Na2SeO3 – strain SeIV, selenate (Na2SeO4 – strain SeVI or both – strain SeIV+VI. The total amount of Se and selenomethionine in biomass increased with increasing concentration of Se in the culturing media. The selenomethionine made up 30–40% of the total Se in biomass. In both the wild type and Se-resistant strains, the activity of thioredoxin reductase, increased rapidly in the presence of the form of selenium for which the given algal strain was not resistant. Conclusion The selenium effect on the green alga Scenedesmus quadricauda was not only dose dependent, but the chemical form of the element was also crucial. With sulfur deficiency, the selenium toxicity increases, indicating interference of Se with sulfur metabolism. The amount of selenium and SeMet in algal biomass was dependent on both the type of compound and its dose. The activity of thioredoxin reductase was affected by selenium treatment in dose-dependent and toxic-dependent manner. The findings implied that the increase in TR activity in algal cells was a stress response to selenium cytotoxicity

Response of selenium changes in blood using cyclic activation analysis

International Nuclear Information System (INIS)

Spyrou, N.M.; Akanle, O.B.; Damyanova, A.A.

1986-01-01

A study was undertaken to investigate the response of selenium uptake and washout in whole blood and its components in healthy subjects, aged 20 to 30 yr, who were given selenium as a supplement to their usual diet, in the form of a yeast tablet (200 mg) containing 100 μg of the element together with vitamins A, C, and E (natural). Selenium has gained worldwide interest not only as an essential trace element but as a potent modifier of environmental hazards and as a naturally occurring toxicant. It is important therefore to investigate the character and the degree of the changes in healthy people on selenium supplementation. Cyclic activation analysis was used for the determination of selenium concentration through the detection of /sup 77m/Se (17.5 s), because of the increased sensitivity of the method and the large number of samples involved

Toward a Framework for Resource Efficiency Evaluation in Industry: Recommendations for Research and Innovation Projects

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Sophie Sfez

2017-01-01

Full Text Available The world is facing a tremendous resource supply challenge. One strategy of regions and nations to address this issue is to encourage research and innovation through funding programs. Most of the time, these programs require that research and innovation projects quantify potential increases in resource efficiency achieved by the projects. However, no consensus exists on how to calculate resource efficiency; therefore, a wide range of approaches is followed. As a result, resource efficiency results are not comparable between projects, and because no rules or guidelines exist to help project developers, the approach followed is not always appropriate. This paper aims to discuss the existing approaches and methods used to evaluate resource efficiency. In this context, resource efficiency is defined as the ratio between the benefits obtained from resources and the impact or amount of resources used. The most challenging step is the determination of this ratio’s denominator because a wide range of methods to quantify resource consumption exist and are being used. They can be classified as gate-to-gate or life cycle based methods and can be subdivided into accounting methods and impact assessment methods. Each method considers different aspects of resources; thus, no single method aims to answer the same research questions. Therefore, project developers must make a well informed choice about which method to use. This paper provides recommendations to support this choice, as well as the overall evaluation and the valorization of the resource efficiency ratio in the framework of research and innovation programs.

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

Selenium containing clays minerals as additive for the discoloration of glass

NARCIS (Netherlands)

Timmer, K.; Limpt, J.A.C. van; Fischer, H.R.

2010-01-01

While selenium is applied as decolorizing agent for flint container glass or tableware glass, the retention of selenium in glass however is very low. Generally more than 75% of the total selenium input sublimes from the glass melt and leaves the clay minerals due to the high volatility of

Efficient resource allocation scheme for visible-light communication system

Science.gov (United States)

Kim, Woo-Chan; Bae, Chi-Sung; Cho, Dong-Ho; Shin, Hong-Seok; Jung, D. K.; Oh, Y. J.

2009-01-01

A visible-light communication utilizing LED has many advantagies such as visibility of information, high SNR (Signal to Noise Ratio), low installation cost, usage of existing illuminators, and high security. Furthermore, exponentially increasing needs and quality of LED have helped the development of visible-light communication. The visibility is the most attractive property in visible-light communication system, but it is difficult to ensure visibility and transmission efficiency simultaneously during initial access because of the small amount of initial access process signals. In this paper, we propose an efficient resource allocation scheme at initial access for ensuring visibility with high resource utilization rate and low data transmission failure rate. The performance has been evaluated through the numerical analysis and simulation results.

Designing the selenium and bladder cancer trial (SELEBLAT, a phase lll randomized chemoprevention study with selenium on recurrence of bladder cancer in Belgium

Directory of Open Access Journals (Sweden)

Goossens Maria E

2012-03-01

Full Text Available Abstract Background In Belgium, bladder cancer is the fifth most common cancer in males (5.2% and the sixth most frequent cause of death from cancer in males (3.8%. Previous epidemiological studies have consistently reported that selenium concentrations were inversely associated with the risk of bladder cancer. This suggests that selenium may also be suitable for chemoprevention of recurrence. Method The SELEBLAT study opened in September 2009 and is still recruiting all patients with non-invasive transitional cell carcinoma of the bladder on TURB operation in 15 Belgian hospitals. Recruitment progress can be monitored live at http://www.seleblat.org. Patients are randomly assigned to selenium yeast (200 μg/day supplementation for 3 years or matching placebo, in addition to standard care. The objective is to determine the effect of selenium on the recurrence of bladder cancer. Randomization is stratified by treatment centre. A computerized algorithm randomly assigns the patients to a treatment arm. All study personnel and participants are blinded to treatment assignment for the duration of the study. Design The SELEnium and BLAdder cancer Trial (SELEBLAT is a phase III randomized, placebo-controlled, academic, double-blind superior trial. Discussion This is the first report on a selenium randomized trial in bladder cancer patients. Trial registration ClinicalTrials.gov identifier: NCT00729287

Ecologic study of serum selenium and upper gastrointestinal cancers in Iran.

Science.gov (United States)

Nouarie, Mehdi; Pourshams, Akram; Kamangar, Farin; Sotoudeh, Masood; Derakhshan, Mohammad Hossein; Akbari, Mohammad Reza; Fakheri, Hafez; Zahedi, Mohammad Javad; Caldwell, Kathleen; Abnet, Christian C; Taylor, Philip R; Malekzadeh, Reza; Dawsey, Sanford M

2004-09-01

Both observational and experimental studies have shown that higher selenium status reduces the risk of upper gastrointestinal cancers in selenium deficient populations. Recent cancer registry data have shown very different rates of esophageal cancer (EC) and gastric cancer (GC) in four Provinces of Iran, namely Ardabil, Mazandaran, Golestan, and Kerman. The aim of this study was to have a preliminary assessment of the hypothesis that high rates of EC in Golestan and high rates of GC in Ardabil may be partly attributable to selenium deficiency. We measured serum selenium in 300 healthy adults from Ardabil (n = 100), Mazandaran (n = 50), Golestan (n = 100), and Kerman (n = 50), using inductively coupled plasma, with dynamic reaction cell, mass spectrometry (ICP-DRC-MS) at the US Centers for Disease Control (Atlanta, Georgia). The median serum selenium concentrations were very different in the four Provinces. The medians (IQR) for selenium in Ardabil, Mazandarn, Golestan, and Kerman were 82 (75-94), 123 (111-132), 155 (141-173), and 119 (110-128) microg/L, respectively (P<0.001). The results of linear regression showed that the Province variable, by itself, explained 76% of the variance in log selenium (r2 = 0.76). The proportion of the populations with a serum selenium more than 90 microg/L (the concentration at which serum selenoproteins are saturated) was 100% in Golestan, Kerman, and Mazandaran but only 29% in Ardabil. Our findings suggest that selenium deficiency is not a major contributor to the high incidence of EC seen in northeastern Iran, but it may play a role in the high incidence of GC in Ardabil Province. Copyright 2004 The WJG Press ISSN

Plasma and breast-milk selenium in HIV-infected Malawian mothers are positively associated with infant selenium status but are not associated with maternal supplementation: results of the Breastfeeding, Antiretrovirals, and Nutrition study.

Science.gov (United States)

Flax, Valerie L; Bentley, Margaret E; Combs, Gerald F; Chasela, Charles S; Kayira, Dumbani; Tegha, Gerald; Kamwendo, Debbie; Daza, Eric J; Fokar, Ali; Kourtis, Athena P; Jamieson, Denise J; van der Horst, Charles M; Adair, Linda S

2014-04-01

Selenium is found in soils and is essential for human antioxidant defense and immune function. In Malawi, low soil selenium and dietary intakes coupled with low plasma selenium concentrations in HIV infection could have negative consequences for the health of HIV-infected mothers and their exclusively breastfed infants. We tested the effects of lipid-based nutrient supplements (LNS) that contained 1.3 times the Recommended Dietary Allowance of sodium selenite and antiretroviral drugs (ARV) on maternal plasma and breast-milk selenium concentrations. HIV-infected Malawian mothers in the Breastfeeding, Antiretrovirals, and Nutrition study were randomly assigned at delivery to receive: LNS, ARV, LNS and ARV, or a control. In a subsample of 526 mothers and their uninfected infants, we measured plasma and breast-milk selenium concentrations at 2 or 6 (depending on the availability of infant samples) and 24 wk postpartum. Overall, mean (± SD) maternal (range: 81.2 ± 20.4 to 86.2 ± 19.9 μg/L) and infant (55.6 ± 16.3 to 61.0 ± 15.4 μg/L) plasma selenium concentrations increased, whereas breast-milk selenium concentrations declined (14.3 ± 11.5 to 9.8 ± 7.3 μg/L) from 2 or 6 to 24 wk postpartum (all P milk selenium from 2 or 6 to 24 wk postpartum (both P milk selenium, but maternal selenium concentrations were positively associated with infant plasma selenium at 2 or 6 and 24 wk postpartum (P milk selenium concentrations. Future research should examine effects of more readily incorporated forms of selenium (ie, selenomethionine) in HIV-infected breastfeeding women.

Comparative effect of organic and inorganic selenium supplementation on selenium status in camel

Directory of Open Access Journals (Sweden)

B. Faye

2014-04-01

Full Text Available Selenium deficiency is widely described in livestock from the Arabian Peninsula, notably in the camel, and selenium supplementation is based on cattle or horse requirements, usually with sodium selenite product. In order to test the effect of organic Se supplementation vs inorganic Se, 24 pregnant camels were subjected to 3 treatment groups starting one month before delivery (control without Se, non-organic bolus, organic Se. Blood, milk and feces samples were collected from one month before delivery to 3 months of lactation. At delivery, the organic group had a significant higher Se concentration (P < 0.01 in serum (8.21 ± 1.38 μg/100 mL and in colostrum (7.27 ± 2.89 μg/100 mL than in inorganic group (3.90 ± 0.68 and 3.72 ± 0.71, respectively and than in control group (5.45 ± 2.38 and 2.70 ± 0.66, respectively. In calf serum, the Se concentration was significantly higher (P < 0.001 in the two supplemented groups (6.32 ± 2.81 and 5.99 ± 3.31 μg/100 mL in organic and inorganic groups, respectively than in control (3.42 ± 1.41 μg/100 mL. The Se in mother serum decreased after parturition but was highly correlated to Se serum in calf and to Se fecal excretion. Se in milk was lower than in colostrum in all groups (P < 0.01. Treatments had no significant effect on somatic cell count. This study revealed that organic supplementation in camel appeared more efficient.

Selenium content in tissues and meat quality in rabbits fed selenium yeast

Czech Academy of Sciences Publication Activity Database

Dokoupilová, A.; Marounek, Milan; Skřivanová, V.; Březina, P.

2007-01-01

Roč. 52, č. 6 (2007), s. 165-169 ISSN 1212-1819 Institutional research plan: CEZ:AV0Z50450515 Keywords : rabbits * selenium * meat Subject RIV: GH - Livestock Nutrition Impact factor: 0.633, year: 2007

Features of selenium metabolism in humans living under the conditions of North European Russia.

Science.gov (United States)

Parshukova, Olga; Potolitsyna, Natalya; Shadrina, Vera; Chernykh, Aleksei; Bojko, Evgeny

2014-08-01

Selenium supplementation and its effects on Northerners have been little studied. The aim of our study was to assess the selenium levels of the inhabitants of North European Russia, the seasonal aspects of selenium supplementation, and the interrelationships between selenium levels and the levels of thyroid gland hormones. To study the particular features of selenium metabolism in Northerners over the course of 1 year, 19 healthy male Caucasian volunteers (18-21 years old) were recruited for the present study. The subjects were military guards in a Northern European region of Russia (Syktyvkar, Russia, 62°N latitude) who spent 6-10-h outdoors daily. The study was conducted over a 12-month period. Selenium levels, glutathione peroxidase (GP) activity, as well as total triiodothyronine (T3), total thyroxin (T4), free thyroxin, free triiodothyronine, and thyrotropin (TSH) levels, were determined in the blood serum. The study subjects showed low levels of plasma selenium throughout the year. We observed a noticeable decrease in plasma selenium levels during the period from May to August, with the lowest levels in July. Selenium levels in the military guards correlated with the levels of selenium-dependent GP enzyme activity throughout the year. Additionally, we demonstrated a significant correlation between selenium and pituitary-thyroid axis hormones (total T3, free T4, and TSH) in periods in which plasma selenium levels were lower than the established normal ranges. Over the course of 1 year, low levels of plasma selenium affect GP activity and thyroid hormone levels in humans living in North European Russia.

Use of sodium hydroxide treated selenium deficient barley to induce vitamin E and selenium deficiency in yearling cattle.

Science.gov (United States)

Rice, D A; McMurray, C H

1986-02-15

Selenium deficient barley grown in Northern Ireland was treated with sodium hydroxide to deplete it of vitamin E. Housed cattle fed a complete diet based on this treated barley developed nutritional degenerative myopathy, showing that spontaneous myopathy in yearling cattle can be the result of vitamin E and selenium deficiency alone. The diet used is as effective and cheaper than others presently in use for inducing degenerative myopathy.

Optimized Energy Efficiency and Spectral Efficiency Resource Allocation Strategies for Phantom Cellular Networks

KAUST Repository

Abdelhady, Amr, M.; Amin, Osama; Alouini, Mohamed-Slim

2016-01-01

Multi-teir hetrogeneous networks have become an essential constituent for next generation cellular networks. Meanwhile, energy efficiency (EE) has been considered a critical design criterion along with the traditional spectral efficiency (SE) metric. In this context, we study power and spectrum allocation for the recently proposed two-teir architecture known as Phantom cellular networks. The optimization framework includes both EE and SE, where we propose an algorithm that computes the SE and EE resource allocation for Phantom cellular networks. Then, we compare the performance of both design strategies versus the number of users, and the ration of Phantom cellresource blocks to the total number or resource blocks. We aim to investigate the effect of some system parameters to acheive improved SE or EE performance at a non-significant loss in EE or SE performance, respectively. It was found that the system parameters can be tuned so that the EE solution does not yield a significant loss in the SE performance.

Optimized Energy Efficiency and Spectral Efficiency Resource Allocation Strategies for Phantom Cellular Networks

KAUST Repository

Abdelhady, Amr, M.

2016-01-06

Multi-teir hetrogeneous networks have become an essential constituent for next generation cellular networks. Meanwhile, energy efficiency (EE) has been considered a critical design criterion along with the traditional spectral efficiency (SE) metric. In this context, we study power and spectrum allocation for the recently proposed two-teir architecture known as Phantom cellular networks. The optimization framework includes both EE and SE, where we propose an algorithm that computes the SE and EE resource allocation for Phantom cellular networks. Then, we compare the performance of both design strategies versus the number of users, and the ration of Phantom cellresource blocks to the total number or resource blocks. We aim to investigate the effect of some system parameters to acheive improved SE or EE performance at a non-significant loss in EE or SE performance, respectively. It was found that the system parameters can be tuned so that the EE solution does not yield a significant loss in the SE performance.

The efficient and sustainable use of environmental resource systems

International Nuclear Information System (INIS)

Gerlagh, R.

1999-02-01

The two main questions in this study are: (1) how to represent environmental resources within a dynamic, competitive economy, and (2) how to specify environmental policies that guarantee the efficient and sustainable use of these resources, and do not require day-to-day intervention. This study is organized as follows. In Chapter 2, both types of dynamic economies (dynastic and overlapping generations or OLG) are formally specified, and existence of equilibrium is proven. In particular, attention is paid to the consequences of including exhaustible resources with amenity values. It is shown that the equilibrium paths exhibit the specific features of path-dependence. This property implies that present policies have non-diminishing effects on future welfare, and points once more to the urgency of policy interventions. Chapter 3 focuses on efficiency aspects and on the capacity of environmental resources to produce an indefinite stream of valuable services. The chapter also introduces ALICE, an applied model that has a single environmental resource that possesses three specific characteristics: the resource has non-negligible amenity value and is therefore valuable, it is exhaustible, but, if no extraction takes place, the resource produces an indefinite stream of valuable services (the amenity value). An example is provided of strictly conservationist policies that create inefficiencies, and it is shown that efficiency is restored if property rights over the resource are given to the present generation, a policy known as grandfathering. However, it is also shown that, compared to the strictly conservationist policy, grandfathering improves welfare of the present generation while reducing it for future generations. Indeed, an unsustainable equilibrium path cannot be ruled out. Next, parameters are chosen such that the numerical outcomes of the stylized model become comparable with those of existing integrated assessment models that include climate change. The

Efficient Resources Provisioning Based on Load Forecasting in Cloud

Directory of Open Access Journals (Sweden)

Rongdong Hu

2014-01-01

Full Text Available Cloud providers should ensure QoS while maximizing resources utilization. One optimal strategy is to timely allocate resources in a fine-grained mode according to application’s actual resources demand. The necessary precondition of this strategy is obtaining future load information in advance. We propose a multi-step-ahead load forecasting method, KSwSVR, based on statistical learning theory which is suitable for the complex and dynamic characteristics of the cloud computing environment. It integrates an improved support vector regression algorithm and Kalman smoother. Public trace data taken from multitypes of resources were used to verify its prediction accuracy, stability, and adaptability, comparing with AR, BPNN, and standard SVR. Subsequently, based on the predicted results, a simple and efficient strategy is proposed for resource provisioning. CPU allocation experiment indicated it can effectively reduce resources consumption while meeting service level agreements requirements.

Loss of selenium in drying and storage of agronomic plant species

DEFF Research Database (Denmark)

Nielsen, Gunnar Gissel

1970-01-01

In two experiments with Se75, loss of selenium from agricultural species was noted during both drying and storage. The loss of selenium during drying was to some extent overshadowed by the influence of self-absorption caused by the water in the fresh material. The results showed that even plant...... material of non-indicator plantslose volatile selenium at drying temperatures of 60°C or higher, and in some cases even at temperatures below 60°C. The results also showed that storage as briquettes gives the lowest storage loss of selenium....

ANALYSIS OF CONSTRAINTS IN RESOURCE USE EFFICIENCY IN ...

African Journals Online (AJOL)

ANALYSIS OF CONSTRAINTS IN RESOURCE USE EFFICIENCY IN MULTIPLE CROPPING SYSTEM BY SMALL-HOLDER FARMERS IN EBONYI STATE OF ... high cost of modern inputs, lack of adequate finance and lack of collaterals among others served as major constraints, which constituted29%, 36%, 33% and 22% ...

Simulation based energy-resource efficient manufacturing integrated with in-process virtual management

Science.gov (United States)

Katchasuwanmanee, Kanet; Cheng, Kai; Bateman, Richard

2016-09-01

As energy efficiency is one of the key essentials towards sustainability, the development of an energy-resource efficient manufacturing system is among the great challenges facing the current industry. Meanwhile, the availability of advanced technological innovation has created more complex manufacturing systems that involve a large variety of processes and machines serving different functions. To extend the limited knowledge on energy-efficient scheduling, the research presented in this paper attempts to model the production schedule at an operation process by considering the balance of energy consumption reduction in production, production work flow (productivity) and quality. An innovative systematic approach to manufacturing energy-resource efficiency is proposed with the virtual simulation as a predictive modelling enabler, which provides real-time manufacturing monitoring, virtual displays and decision-makings and consequentially an analytical and multidimensional correlation analysis on interdependent relationships among energy consumption, work flow and quality errors. The regression analysis results demonstrate positive relationships between the work flow and quality errors and the work flow and energy consumption. When production scheduling is controlled through optimization of work flow, quality errors and overall energy consumption, the energy-resource efficiency can be achieved in the production. Together, this proposed multidimensional modelling and analysis approach provides optimal conditions for the production scheduling at the manufacturing system by taking account of production quality, energy consumption and resource efficiency, which can lead to the key competitive advantages and sustainability of the system operations in the industry.

Association between Toenail Mercury and Metabolic Syndrome Is Modified by Selenium

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Kyong Park

2016-07-01

Full Text Available Background: Although Asian populations consume relatively large amounts of fish and seafood and have a high prevalence of metabolic diseases, few studies have investigated the association between chronic mercury exposure and metabolic syndrome and its effect modification by selenium. Methods: We analyzed baseline data from the Trace Element Study of Korean Adults in the Yeungnam area. Participants included 232 men and 269 women, aged 35 years or older, who had complete data regarding demographic, lifestyle, diet, toenail mercury and selenium levels, and health. Toenail mercury and selenium concentrations were measured using instrumental neutron-activation analysis. The metabolic biomarker levels were obtained through biannual medical checkups. Results: Higher toenail mercury levels were associated with habitual consumption of whale and shark meats, older age, obesity, smoking, alcohol drinking, and higher household income. Multivariable analysis showed a positive association between toenail mercury exposure and metabolic syndrome. In addition, this association was significantly stronger at lower selenium levels and was weaker at higher selenium levels. Conclusion: The possible harmful effects of mercury on metabolic syndrome may be attenuated by high levels of selenium. Future studies are needed to suggest optimal dietary guidelines regarding fish and selenium intakes, particularly for Asians with high levels of fish intake.

Inter-individual variation of selenium in maternal plasma, cord plasma and placenta

International Nuclear Information System (INIS)

Lee, Anne M.; Huel, Guy; Godin, Jean; Hellier, Georgette; Sahuquillo, Josiane; Moreau, Thierry; Blot, Phillipe

1994-01-01

Selenium (Se) in high doses has been known to cause injury to the fetus and newborn. The major difficulty in assessing the effects of selenium on human reproduction stems from the need for a suitable means of estimating maternal and fetal exposure. The present investigation, therefore, examines the respective reliability of maternal plasma, cord plasma and placenta as epidemiological indicators as well as inter-individual variation of this trace element. An unselected population of 128 pregnancies was studied. Obstetrical characteristics were noted. Selenium concentrations were determined for maternal plasma, cord plasma, and placental tissue by fluorometric analysis. Maternal plasma selenium concentrations (Se-Bm) were significantly greater than fetal concentrations (Se-Bc). Placental selenium (Se-Pl) levels were four times that of fetal levels. Variability of Se-Bc is best explained by placental concentrations. Maternal weight and ethnic origin are significantly correlated with Se-Bc. Female newborn have higher selenium levels than male newborn. The present study demonstrates the significance of the placenta as an indicator of fetal selenium exposure

Preparation and characterization of a laboratory scale selenomethionine-enriched bread. Selenium bioaccessibility.

Science.gov (United States)

Sánchez-Martínez, María; Pérez-Corona, Teresa; Caímara, Carmen; Madrid, Yolanda

2015-01-14

This study focuses on the preparation at lab scale of selenomethionine-enriched white and wholemeal bread. Selenium was supplemented either by adding selenite directly to the dough or by using lab-made selenium-enriched yeast. The best results were obtained when using fresh selenium-enriched yeast. The optimum incubation time for selenomethionine-enriched yeast preparation, while keeping formation of selenium byproducts to a minimum, was 96 h. Selenium content measured by isotope dilution analysis (IDA)-ICP-MS in Se-white and Se-wholemeal bread was 1.28 ± 0.02 μg g–1 and 1.16 ± 0.02 μg g–1 (expressed as mean ± SE, 3 replicates), respectively. HPLC postcolumn IDA-ICP-MS measurements revealed that selenomethionine was the main Se species found in Se-enriched bread, which accounted for ca. 80% of total selenium. In vitro gastrointestinal digestion assay provided selenium bioaccessibility values of 100 ± 3% and 40 ± 1% for white and wholemeal Se-enriched bread, respectively, being selenomethionine the main bioaccessible Se species in white bread, while in wholemeal bread this compound was undetectable.

Recent Microextraction Techniques for Determination and Chemical Speciation of Selenium

Directory of Open Access Journals (Sweden)

Ibrahim Ahmed S. A.

2017-05-01

Full Text Available Research designed to improve extraction has led to the development of microextraction techniques (ME, which involve simple, low cost, and effective preconcentrationof analytes in various matrices. This review is concerned with the principles and theoretical background of ME, as well as the development of applications for selenium analysis during the period from 2008 to 2016. Among all ME, dispersive liquid-liquid microextraction was found to be most favorable for selenium. On the other hand, atomic absorption spectrometry was the most frequently used instrumentation. Selenium ME have rarely been coupled to spectrophotometry and X-ray spectrophotometry methods, and there is no published application of ME with electrochemical techniques. We strongly support the idea of using a double preconcentration process, which consists of microextraction prior to preconcentration, followed by selenium determination using cathodic stripping voltammetry (ME-CSV. More attention should focus on the development of accurate, precise, and green methods for selenium analysis.

Selenium Exposure and Cancer Risk: an Updated Meta-analysis and Meta-regression

Science.gov (United States)

Cai, Xianlei; Wang, Chen; Yu, Wanqi; Fan, Wenjie; Wang, Shan; Shen, Ning; Wu, Pengcheng; Li, Xiuyang; Wang, Fudi

2016-01-01

The objective of this study was to investigate the associations between selenium exposure and cancer risk. We identified 69 studies and applied meta-analysis, meta-regression and dose-response analysis to obtain available evidence. The results indicated that high selenium exposure had a protective effect on cancer risk (pooled OR = 0.78; 95%CI: 0.73–0.83). The results of linear and nonlinear dose-response analysis indicated that high serum/plasma selenium and toenail selenium had the efficacy on cancer prevention. However, we did not find a protective efficacy of selenium supplement. High selenium exposure may have different effects on specific types of cancer. It decreased the risk of breast cancer, lung cancer, esophageal cancer, gastric cancer, and prostate cancer, but it was not associated with colorectal cancer, bladder cancer, and skin cancer. PMID:26786590

Selenium status and cancer mortality in subjects residing in four Canadian provinces

International Nuclear Information System (INIS)

Morris, J.S.; Horsman, T.L.; Spate, V.L.; Baskett, C.K.; Mason, M.M.; Nichols, T.A.; Rohan, T.; Soskolne, C.L.; Jain, M.

2001-01-01

Selenium status in male and female Canadian subjects was measured relative to cancer mortality in their respective provinces. Toenail specimens from 755 subjects, 377 males and 378 females, living in Vancouver (186), Edmonton (188), Toronto (197) and Montreal (184) were analyzed by instrumental neutron activation analysis giving means of 0.968 ± 0.177, 0.950 ± 0.148, 0.932 ± 0.135 and 0.896 ± 0.127 ppm Se, respectively. The effect of selenium determinants such as gender, selenium supplementation and smoking on selenium status is presented. Details of the observed inverse relationship of selenium status and cancer mortality are discussed. (author)

Resource values in analyzing fire management programs for economic efficiency

Science.gov (United States)

Irene A. Althaus; Thomas J. Mills

1982-01-01

In analyzing fire management programs for their economic efficiency, it is necessary to assign monetary values to the changes in resource outputs caused by, fire. The derivation of resource values is complicated by imperfect or nonexistent commercial market structures. The valuation concept recommended for fire program analyses is willingness-to-pay because it permits...

Cross-species global and subset gene expression profiling identifies genes involved in prostate cancer response to selenium

Directory of Open Access Journals (Sweden)

Dhir Rajiv

2004-08-01

Full Text Available Abstract Background Gene expression technologies have the ability to generate vast amounts of data, yet there often resides only limited resources for subsequent validation studies. This necessitates the ability to perform sorting and prioritization of the output data. Previously described methodologies have used functional pathways or transcriptional regulatory grouping to sort genes for further study. In this paper we demonstrate a comparative genomics based method to leverage data from animal models to prioritize genes for validation. This approach allows one to develop a disease-based focus for the prioritization of gene data, a process that is essential for systems that lack significant functional pathway data yet have defined animal models. This method is made possible through the use of highly controlled spotted cDNA slide production and the use of comparative bioinformatics databases without the use of cross-species slide hybridizations. Results Using gene expression profiling we have demonstrated a similar whole transcriptome gene expression patterns in prostate cancer cells from human and rat prostate cancer cell lines both at baseline expression levels and after treatment with physiologic concentrations of the proposed chemopreventive agent Selenium. Using both the human PC3 and rat PAII prostate cancer cell lines have gone on to identify a subset of one hundred and fifty-four genes that demonstrate a similar level of differential expression to Selenium treatment in both species. Further analysis and data mining for two genes, the Insulin like Growth Factor Binding protein 3, and Retinoic X Receptor alpha, demonstrates an association with prostate cancer, functional pathway links, and protein-protein interactions that make these genes prime candidates for explaining the mechanism of Selenium's chemopreventive effect in prostate cancer. These genes are subsequently validated by western blots showing Selenium based induction and using

Energy Efficient Resource Allocation for Cognitive Radios: A Generalized Sensing Analysis

KAUST Repository

Alabbasi, AbdulRahman; Rezki, Zouheir; Shihada, Basem

2014-01-01

In this paper, two resource allocation schemes for energy efficient cognitive radio systems are proposed. Our design considers resource allocation approaches that adopt spectrum sharing combined with soft-sensing information, adaptive sensing thresholds, and adaptive power to achieve an energy efficient system. An energy per good-bit metric is considered as an energy efficient objective function. A multi-carrier system, such as, orthogonal frequency division multiplexing, is considered in the framework. The proposed resource allocation schemes, using different approaches, are designated as sub-optimal and optimal. The sub-optimal approach is attained by optimizing over a channel inversion power policy. The optimal approach utilizes the calculus of variation theory to optimize a problem of instantaneous objective function subject to average and instantaneous constraints with respect to functional optimization variables. In addition to the analytical results, selected numerical results are provided to quantify the impact of soft-sensing information and the optimal adaptive sensing threshold on the system performance.

Energy Efficient Resource Allocation for Cognitive Radios: A Generalized Sensing Analysis

KAUST Repository

Alabbasi, Abdulrahman

2014-12-31

In this paper, two resource allocation schemes for energy efficient cognitive radio systems are proposed. Our design considers resource allocation approaches that adopt spectrum sharing combined with soft-sensing information, adaptive sensing thresholds, and adaptive power to achieve an energy efficient system. An energy per good-bit metric is considered as an energy efficient objective function. A multi-carrier system, such as, orthogonal frequency division multiplexing, is considered in the framework. The proposed resource allocation schemes, using different approaches, are designated as sub-optimal and optimal. The sub-optimal approach is attained by optimizing over a channel inversion power policy. The optimal approach utilizes the calculus of variation theory to optimize a problem of instantaneous objective function subject to average and instantaneous constraints with respect to functional optimization variables. In addition to the analytical results, selected numerical results are provided to quantify the impact of soft-sensing information and the optimal adaptive sensing threshold on the system performance.

Characterization of selenium doped silica glasses synthesized by sol-gel method

International Nuclear Information System (INIS)

Kobayashi, R.A.; Toffoli, S.M.

2012-01-01

Selenium is a rare element in nature. It is used in the food, pharmaceutical, and glass industries. In commercial glasses, selenium is the element responsible for most of the pink or light red color, but its effect is primarily dependent on the oxidation state of the element in the glassy matrix. Besides, selenium is highly volatile, and as high as 80 wt% may be lost in the furnace during the industrial glass elaboration. The sol– gel method yields synthesized materials of high purity and homogeneity, and uses low processing temperatures. Samples of silica glass were obtained by sol-gel method, incorporating precursors of selenium, with the main objective of reducing selenium losses during its heating. The results of optical absorption, XRD and thermal analysis (TGA, DSC) of the glasses are presented and discussed. (author)

Concentrations of boron, molybdenum, and selenium in chinook salmon

Science.gov (United States)

Hamilton, Steven J.; Wiedmeyer, Raymond H.

1990-01-01

The concentrations of boron, molybdenum, and selenium in young chinook salmon Oncorhynchus tshawytscha were determined in three partial life cycle chronic toxicity studies. In each study, fish were exposed to a mixture of boron, molybdenum, selenate, and selenite in the proportions found in subsurface agricultural drainage water in the basin of the San Joaquin Valley, California. Tests were conducted in well water and in site-specific fresh and brackish waters. No boron or molybdenum was detected in fish exposed to concentrations as high as 6,046 μg boron/L and 193 μg molybdenum/L for 90 d in well water or fresh water; however, whole-body concentrations of selenium increased with increasing exposure concentrations in well water and fresh water, but not in brackish water. Concentrations of selenium in chinook salmon were strongly correlated with reduced survival and growth of fish in well water and with reduced survival in a 15-d seawater challenge test of fish from fresh water. Concentrations of selenium in fish seemed to reach a steady state after 60 d of exposure in well water or fresh water. Fish in brackish water had only background concentrations of selenium after 60 d of exposure, and no effects on survival and growth in brackish water or on survival in a 10-d seawater challenge test were exhibited. This lack of effect in brackish water was attributed to initiation of the study with advanced fry, which were apparently better able to metabolize the trace element mixture than were the younger fish used in studies with well water and fresh water. In all three experimental waters, concentration factors (whole-body concentration/waterborne concentration) for selenium decreased with increasing exposure concentrations, suggesting decreased uptake or increased excretion, or both, of selenium at the higher concentrations.

Selenium Treatment Technologies

Science.gov (United States)

Selenium (Se) is a metalloid that is a dietary requirement in small quantities, but toxic at higher quantities. It also is known to bioaccumulate. In oxic environments, it exists as selenate (+6) and selenite (+4), both of which are soluble. Selenite will sorb more strongly to...

Evaluation on equality and efficiency of health resources allocation and health services utilization in China.

Science.gov (United States)

Sun, Jian; Luo, Hongye

2017-07-14

China is faced with a daunting challenge to equality and efficiency in health resources allocation and health services utilization in the context of rapid economic growth. This study sought to evaluate the equality and efficiency of health resources allocation and health services utilization in China. Demographic, economic, and geographic area data was sourced from China Statistical Yearbook 2012-2016. Data related to health resources and health services was obtained from China Health Statistics Yearbook 2012-2016. Furthermore, we evaluated the equality of health resources allocation based on Gini coefficient. Concentration index was used to measure the equality in utilization of health services. Data envelopment analysis (DEA) was employed to assess the efficiency of health resources allocation. From 2011 to 2015, the Gini coefficients for health resources by population ranged between 0.0644 and 0.1879, while the Gini coefficients for the resources by geographic area ranged from 0.6136 to 0.6568. Meanwhile, the concentration index values for health services utilization ranged from -0.0392 to 0.2110. Moreover, in 2015, 10 provinces (32.26%) were relatively efficient in terms of health resources allocation, while 7 provinces (22.58%) and 14 provinces (45.16%) were weakly efficient and inefficient, respectively. There exist distinct regional disparities in the distribution of health resources in China, which are mainly reflected in the geographic distribution of health resources. Furthermore, the people living in the eastern developed areas are more likely to use outpatient care, while the people living in western underdeveloped areas are more likely to use inpatient care. Moreover, the efficiency of health resources allocation in 21 provinces (67.74%) of China was low and needs to be improved. Thus, the government should pay more attention to the equality based on geographic area, guide patients to choose medical treatment rationally, and optimize the resource

Radiation protection effect of selenium on the Rat's prostate

Energy Technology Data Exchange (ETDEWEB)

Choi, Hyung Seok; Choi, Jun Hyeok; Jung, Do Young; Kim, Jang Oh; Shin, Ji Hye; Kim, Joo Hee; Min, Byung In [Inje University, Kimhae (Korea, Republic of)

2017-06-15

High-tech medical equipment has increased the utilization of radiation in the medical field. As a result, research on radiation protection using natural materials has become an important social issue. Selenium is a natural substance that is highly expressed in prostate known that an essential role in prostate cells. Selenium was orally administered to Rat and irradiated with 10 Gy of radiation. Then, the prostate tissue was used as a target organ for 1 day, 7 days and 21 days to investigate the radiation protection effect of selenium through changes of blood components, Superoxide Dismutase and histological changes. As a result, there was a significant protective effect of hematopoietic immune system(hemoglobin concentration, neutrophil, platelet) in the group irradiated with selenium(p<0.05). The observation of tissue changes selenium is an effective component to increase Superoxide Dismutase activity, and it was confirmed that it has an effect of inhibiting the expression of hypertrophy of prostate by irradiation. Therefore, it is considered that selenium can be utilized as a radioprotective agent by inducing prevention of prostate-related diseases.

Integrating resource efficiency and EU State aid. An evaluation of resource efficiency considerations in the current EU State aid framework

Energy Technology Data Exchange (ETDEWEB)

Bennink, D.; Faber, J.; Smit, M. [CE Delft, Delft (Netherlands); Goba, V. [SIA Estonian, Latvian and Lithuanian Environment ELLE, Tallinn (Estonia); Miller, K.; Williams, E. [AEA Technology plc, London (United Kingdom)

2012-10-15

This study, for the European Commission, analyses the issues that need to be addressed in the revision of the EU State aid framework to ensure that they do not hinder environmental, resource efficiency and sustainable development goals. In some cases, State aid can be considered an environmentally harmful subsidy (EHS). The study analyses (1) the extent to which the Environmental Aid Guidelines (EAG) need to be changed to take into account recent European environmental policy developments; (2) existing and potential resource efficiency considerations in a) the Regional Aid Guidelines; b) the Research, Development and Innovation (RDI) Guidelines and c) the Agriculture and Forestry Guidelines; assesses cases and schemes using these guidelines to identify whether resource efficiency considerations are taken into account. The study also considers the social, environmental and economic impacts of these cases and schemes. It develops recommendations for the review of the EAG and a number of horizontal guidelines. One of the conclusions of the analysis is that the way in which multiple objectives and impacts are balanced, when deciding to approve state aid, is unclear. Also, EU member states are not required to provide information on certain types of (estimated) impacts. To guarantee that multiple objectives and impacts are sufficiently balanced, it is recommended that the State aid framework prescribes that applicants identify social, economic and environmental objectives and impacts and describe how these are taken into account in the procedure of balancing multiple (conflicting) objectives. Objectives and impacts should be quantified as much as possible, for example by making use of the method of external cost calculation laid down in 'the Handbook on estimation of external costs in the transport Sector'. The results of the study are used by the European Commission as an input for evaluating and improving the EU State aid framework.

Integrating resource efficiency and EU State aid. An evaluation of resource efficiency considerations in the current EU State aid framework

Energy Technology Data Exchange (ETDEWEB)

Bennink, D.; Faber, J.; Smit, M. [CE Delft, Delft (Netherlands); Goba, V. [SIA Estonian, Latvian and Lithuanian Environment ELLE, Tallinn (Estonia); Miller, K.; Williams, E. [AEA Technology plc, London (United Kingdom)

2012-10-15

This study, for the European Commission, analyses the issues that need to be addressed in the revision of the EU State aid framework to ensure that they do not hinder environmental, resource efficiency and sustainable development goals. In some cases, State aid can be considered an environmentally harmful subsidy (EHS). The study analyses (1) the extent to which the Environmental Aid Guidelines (EAG) need to be changed to take into account recent European environmental policy developments; (2) existing and potential resource efficiency considerations in a) the Regional Aid Guidelines; b) the Research, Development and Innovation (RDI) Guidelines and c) the Agriculture and Forestry Guidelines; assesses cases and schemes using these guidelines to identify whether resource efficiency considerations are taken into account. The study also considers the social, environmental and economic impacts of these cases and schemes. It develops recommendations for the review of the EAG and a number of horizontal guidelines. One of the conclusions of the analysis is that the way in which multiple objectives and impacts are balanced, when deciding to approve state aid, is unclear. Also, EU member states are not required to provide information on certain types of (estimated) impacts. To guarantee that multiple objectives and impacts are sufficiently balanced, it is recommended that the State aid framework prescribes that applicants identify social, economic and environmental objectives and impacts and describe how these are taken into account in the procedure of balancing multiple (conflicting) objectives. Objectives and impacts should be quantified as much as possible, for example by making use of the method of external cost calculation laid down in 'the Handbook on estimation of external costs in the transport Sector'. The results of the study are used by the European Commission as an input for evaluating and improving the EU State aid framework.

EFFECT OF SELENIUM SUPPLEMENTATION ON PIG PRODUCTION PROPERTIES, ANTIOXIDANT STATUS AND MEAT QUALITY

Directory of Open Access Journals (Sweden)

Tomislav Šperanda

2013-12-01

Full Text Available Food containing functional ingredients to achieve a positive effect on health and reducing the risk of infection is increasing production. It is also very important to improve the quality of pork with respect to change the genetic makeup of pigs that raised leanness, being inversely correlated with the quality of meat. This study monitored the effectiveness of addition of higher doses of organic selenium in the diet of fattening pigs in relation to their growth, immunity, antioxidant power, the quality of meat and possibility of meat enriching with selenium. The experiment was carried out on 100 pigs (crossbred WJxSLxP of both sexes, from 28 kg to 98 kg body weight during a period of 98 days. Piglets fed the finished feed mixture for fattening up to 60 kg (ST-1 and a mixture for fattening up to 100 kg (DM-2 in addition, by the groups as follows: K-0. 3 mg/kg organic selenium, P1-0.5 mg/kg inorganic selenium, P2-0.5 mg/kg organic selenium, P3-0.5 mg/ kg organic selenium +0.2% zeolite clinoptilolite treated vibrotehnology and P4-gradual increase in selenium so that the concentration of the last month was 0.7 mg/ kg diet of organic selenium. All groups of pigs fed high concentration of organic selenium had a higher proportion of lymphocytes, especially CD4 T lymphocytes. Glutathione peroxidase activity was higher in all groups fed elevated selenium levels and significantly higher in the P3 and P4 groups 71st and 98th days of the trials. Glutathione reductase was significantly higher in the P3 and P4 group 98th days compared to the control. Antioxidant indicators suggested increased antioxidant protection in groups supplemented with 0.5 ppm organic selenium and selenium formulations of the same with the addition of zeolite under stress intensive pig production. No differences were found in the products of lipid peroxidation (TBARS in raw meat or in meat after a week in refrigerator storage. By histological examination statistically higher level of

Total selenium in irrigation drain inflows to the Salton Sea, California, April 2009

Science.gov (United States)

May, Thomas W.; Walther, Michael J.; Saiki, Michael K.; Brumbaugh, William G.

2009-01-01

This report presents the results for the final sampling period (April 2009) of a 4-year monitoring program to characterize selenium concentrations in selected irrigation drains flowing into the Salton Sea, California. Total selenium and total suspended solids were determined in water samples. Total selenium, percent total organic carbon, and particle size were determined in sediments. Mean total selenium concentrations in water ranged from 0.98 to 22.9 micrograms per liter. Total selenium concentrations in sediment ranged from 0.078 to 5.0 micrograms per gram dry weight.

Shape coexistence in selenium isotopes

International Nuclear Information System (INIS)

Liu Ying; Cao Zhongbin; Xu Furong

2010-01-01

Nuclear shape change and shape coexistence in the Selenium isotopes have been investigated by Total-Routhian-Surface (TRS) calculations. It is found that nuclear shapes vary significantly with increasing neutron number. The TRS calculations for the ground states of 66,72,92,94 Se isotopes show that both neutron-deficient and neutron-dripline Selenium isotopes have oblate and prolate shape coexistence. The cranking shell-model calculations for 72,94 Se give that prolate and oblate shape coexistence in low rotational frequency. However, oblate rotational bands disappear and prolate rotational bands become yrast bands with increasing rotational frequency, which is due to the intrusion of the g 9/2 orbitals. (authors)

Redox-Active Selenium Compounds—From Toxicity and Cell Death to Cancer Treatment

Directory of Open Access Journals (Sweden)

Sougat Misra

2015-05-01

Full Text Available Selenium is generally known as an antioxidant due to its presence in selenoproteins as selenocysteine, but it is also toxic. The toxic effects of selenium are, however, strictly concentration and chemical species dependent. One class of selenium compounds is a potent inhibitor of cell growth with remarkable tumor specificity. These redox active compounds are pro-oxidative and highly cytotoxic to tumor cells and are promising candidates to be used in chemotherapy against cancer. Herein we elaborate upon the major forms of dietary selenium compounds, their metabolic pathways, and their antioxidant and pro-oxidant potentials with emphasis on cytotoxic mechanisms. Relative cytotoxicity of inorganic selenite and organic selenocystine compounds to different cancer cells are presented as evidence to our perspective. Furthermore, new novel classes of selenium compounds specifically designed to target tumor cells are presented and the potential of selenium in modern oncology is extensively discussed.

Binding and Conversion of Selenium in Candida utilis ATCC 9950 Yeasts in Bioreactor Culture

Directory of Open Access Journals (Sweden)

Marek Kieliszek

2017-02-01

Full Text Available Selenium is considered an essential component of all living organisms. The use of yeasts as a selenium supplement in human nutrition has gained much interest over the last decade. The accumulation and biochemical transformation of selenium in yeast cells is particularly interesting to many researchers. In this article, we present the results of the determination of selenium and selenomethionine content in the biomass of feed yeast Candida utilis ATCC 9950 obtained from the culture grown in a bioreactor. The results indicated that C. utilis cells performed the biotransformation of inorganic selenium(IV to organic derivatives (e.g., selenomethionine. Selenium introduced (20–30 mg Se4+∙L−1 to the experimental media in the form of sodium(IV selenite (Na2SeO3 salt caused a significant increase in selenium content in the biomass of C. utilis,irrespective of the concentration. The highest amount of selenium (1841 μg∙gd.w.−1 was obtained after a 48-h culture in media containing 30 mg Se4+∙L−1. The highest content of selenomethionine (238.8 μg∙gd.w.−1 was found after 48-h culture from the experimental medium that was supplemented with selenium at a concentration of 20 mg Se4+∙L−1. Biomass cell in the cultures supplemented with selenium ranged from 1.5 to 14.1 g∙L−1. The results of this study indicate that yeast cell biomass of C. utilis enriched mainly with the organic forms of selenium can be a valuable source of protein. It creates the possibility of obtaining selenium biocomplexes that can be used in the production of protein-selenium dietary supplements for animals and humans

Selenium supplementation for Hashimoto's thyroiditis.

Science.gov (United States)

van Zuuren, Esther J; Albusta, Amira Y; Fedorowicz, Zbys; Carter, Ben; Pijl, Hanno

2013-06-06

Hashimoto's thyroiditis is a common auto-immune disorder. The most common presenting symptoms may include anxiety, negative mood, depression, dry skin, cold intolerance, puffy eyes, muscle cramps and fatigue, deep voice, constipation, slow thinking and poor memory. Clinical manifestations of the disease are defined primarily by low levels of thyroid hormones; therefore it is treated by hormone replacement therapy, which usually consists of levothyroxine (LT4). Selenium might reduce antibody levels and result in a decreased dosage of LT4 and may provide other beneficial effects (e.g. on mood and health-related quality of life). To assess the effects of selenium supplementation on Hashimoto's thyroiditis. We searched the following databases up to 2 October 2012: CENTRAL in The Cochrane Library (2012, Issue 10), MEDLINE, EMBASE, and Web of Science; we also screened reference lists of included studies and searched several online trial registries for ongoing trials (5 November 2012). Randomised controlled clinical trials that assessed the effects of selenium supplementation for adults diagnosed with Hashimoto's thyroiditis. Study selection, data extraction, assessment of risk of bias, and analyses were carried out by two independent review authors. We assessed the quality of the evidence of included studies using GRADE. We were unable to conduct a meta-analysis because clinical heterogeneity between interventions that were investigated is substantial. Four studies at unclear to high risk of bias comprising 463 participants were included. The mean study duration was 7.5 months (range 3 to 18 months). One of our primary outcomes－'change from baseline in health related quality of life'－and two of our secondary outcomes－'change from baseline in LT4 replacement dosage at end of the study' and 'economic costs'－were not assessed in any of the studies. One study at high risk of bias showed statistically significant improvement in subjective well-being with sodium

Resource-Use Efficiency in Rice Production Under Small Scale ...

African Journals Online (AJOL)

acer

specific objectives of the study were to determine resource use efficiency, describe ... economic level. ... this key variable with a view to stepping ... focused on small-scale irrigation systems for ... farmers were assumed to be operating under.

The effect of resource quantity and resource stoichiometry on microbial carbon-use-efficiency

Science.gov (United States)

Kleiblinger, K.M.; Hall, E.K.; Wanek, W.; Szukics, U.; Hämmerle, I.; Ellersdorfer, G.; Böck, S.; Strauss, J.; Sterflinger, K.; Richter, A.; Zechmeister-Boltenstern, S.

2010-01-01

The carbon-use-efficiency (CUE) of microorganisms is an important parameter in determining ecosystem-level carbon (C) cycling; however, little is known about how variance in resources affects microbial CUE. To elucidate how resource quantity and resource stoichiometry affect microbial CUE, we cultured four microorganisms - two fungi (Aspergillus nidulans and Trichoderma harzianum) and two bacteria (Pectobacterium carotovorum and Verrucomicrobium spinosum) - under 12 unique C, nitrogen (N) and phosphorus (P) ratios. Whereas the CUE of A. nidulans was strongly affected by C, bacterial CUE was more strongly affected by mineral nutrients (N and P). Specifically, CUE in P. carotovorum was positively correlated with P, while CUE of V. spinosum primarily depended on N. This resulted in a positive relationship between fungal CUE and resource C : nutrient stoichiometry and a negative relationship between bacterial CUE and resource C : nutrient stoichiometry. The difference in the direction of the relationship between CUE and C : nutrient for fungi vs. bacteria was consistent with differences in biomass stoichiometry and suggested that fungi have a higher C demand than bacteria. These results suggest that the links between biomass stoichiometry, resource demand and CUE may provide a mechanism for commonly observed temporal and spatial patterns in microbial community structure and function in natural habitats.

On-line pre-reduction of Se(VI) by thiourea for selenium speciation by hydride generation

International Nuclear Information System (INIS)

Qiu Jianhua; Wang Qiuquan; Ma Yuning; Yang Limin; Huang Benli

2006-01-01

In this study, thiourea (TU) was novelly developed as a reduction reagent for on-line pre-reduction of selenium(VI) before conventional hydride generation (HG) by KBH 4 /NaOH-HCl. After TU on-line pre-reduction, the HG efficiency of Se(VI) has been greatly improved and because even higher than that of the same amount of Se(IV) obtained in the conventional HG system. The possible pre-reduction mechanism is discussed. The detection limit (DL) of selenate reaches 10 pg mL -1 when using on-line TU pre-reduction followed by HG atomic fluorescence detection. When TU pre-reduction followed by HG is used as an interface between ion-pair high performance liquid chromatography and atomic fluorescence spectrometry, selenocystine, selenomethionine, selenite and selenate can be measured simultaneously and quantitatively. The DLs of these are 0.06, 0.08, 0.05 and 0.04 ng mL -1 , respectively, and the relative standard deviations of 9 duplicate runs for all the 4 species are less than 5%. Furthermore, it was successfully applied to Se speciation analysis of cultured garlic samples, and validated by determination of total selenium and selenium species in certified reference material NIST 1946

Microgravimetric Studies of Selenium Electrodeposition Onto Different Substrates

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Kowalik R.

2014-10-01

Full Text Available The mechanism of selenium electrodeposition from sulfuric acid solution on different substrates was studied with the electrochemical techniques. The cyclic voltammetry was combined with the quartz crystal microbalance technique to analyze selenium deposition process. The electrochemical reduction of selenous acid on gold, silver and copper electrodes was investigated. It was found that reduction of selenous acid is a very complex process and it strongly depends from the applied substrate. The voltammetric measurements indicate the range of potentials in which the process of reduction of selenous acids on the applied substrate is possible. Additionally, the microgravimetric data confirm the deposition of selenium and they reveal the mechanism of the deposition process.

Resource Efficient LDPC Decoders for Multimedia Communication

OpenAIRE

Chandrasetty, Vikram Arkalgud; Aziz, Syed Mahfuzul

2013-01-01

Achieving high image quality is an important aspect in an increasing number of wireless multimedia applications. These applications require resource efficient error correction hardware to detect and correct errors introduced by the communication channel. This paper presents an innovative flexible architecture for error correction using Low-Density Parity-Check (LDPC) codes. The proposed partially-parallel decoder architecture utilizes a novel code construction technique based on multi-level H...

EFFICIENCY OF THE USE OF AUTHENTIC WEB-RESOURCES IN TRANSLATORS TRAINING

OpenAIRE

Iryna M. Drobit; Nataliia V. Rak

2013-01-01

The article deals with pedagogical assumptions and efficiency of the use of Information and Communication Technologies, especially authentic web-resources, while teaching language for specific purposes (translators and interpreters). Accuracy, content, and functionality of web-resource TED, which contains examples of authentic speech in English, have been outlined. It has been demonstrated that usage of multimedia and communication facilities of the TED web-resource provides favourable opport...

Selenium Poisoning of Wildlife and Western Agriculture: Cause and Effect

Energy Technology Data Exchange (ETDEWEB)

Korte, N.E.

2000-02-01

This project examined the hypothesis that selenium contamination is not the principal cause of the decline of endemic fish species in the Upper Colorado Basin. Activities employed to test this hypothesis included a reconnaissance of locations altered by recent road construction, a re-interpretation of available literature regarding selenium toxicity, and the interpretation of unpublished data obtained from the Upper Colorado Basin Fish Recovery Program. The project demonstrates that most of the evidence implicating selenium is circumstantial.

21 CFR 522.2100 - Selenium, vitamin E injection.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Selenium, vitamin E injection. 522.2100 Section... § 522.2100 Selenium, vitamin E injection. (a)(1) Specifications. The drug is an emulsion containing in... of vitamin E (68 I.U.) (as d-alpha tocopheryl acetate). (2) Sponsor. See No. 000061 in § 510.600(c...

Identification and characterization of a selenium-dependent glutathione peroxidase in Setaria cervi

International Nuclear Information System (INIS)

Singh, Anchal; Rathaur, Sushma

2005-01-01

Setaria cervi a bovine filarial parasite secretes selenium glutathione peroxidase during in vitro cultivation. A significant amount of enzyme activity was detected in the somatic extract of different developmental stages of the parasite. Among different stages, microfilariae showed a higher level of selenium glutathione peroxidase activity followed by males then females. However, when the activity was compared in excretory secretory products of these stages males showed higher activity than microfilariae and female worms. The enzyme was purified from female somatic extract using a combination of glutathione agarose and gel filtration chromatography, which migrated as a single band of molecular mass ∼20 kDa. Selenium content of purified enzyme was estimated by atomic absorption spectroscopy and found to be 3.5 ng selenium/μg of protein. Further, inhibition of enzyme activity by potassium cyanide suggested the presence of selenium at the active site of enzyme. This is the first report of identification of selenium glutathione peroxidase from any filarial parasite

Energy-Efficient Resource and Power Allocation for Underlay Multicast Device-to-Device Transmission

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Fan Jiang

2017-11-01

Full Text Available In this paper, we present an energy-efficient resource allocation and power control scheme for D2D (Device-to-Device multicasting transmission. The objective is to maximize the overall energy-efficiency of D2D multicast clusters through effective resource allocation and power control schemes, while considering the quality of service (QoS requirements of both cellular users (CUs and D2D clusters. We first build the optimization model and a heuristic resource and power allocation algorithm is then proposed to solve the energy-efficiency problem with less computational complexity. Numerical results indicate that the proposed algorithm outperforms existing schemes in terms of throughput per energy consumption.

Selenium and tellurium reagents in organic synthesis

International Nuclear Information System (INIS)

Comasseto, J.V.

1984-01-01

A review of the contribution of the University of Sao Paulo (SP, Brazil) to the organic synthesis of selenium and tellurium reagents is made. Major reactions amoung selenium compounds and insaturated substrates, phosphorus, ester enolates as well as the use of phase transference catalysed reactions to produce arylselenolate are described. For tellurium, interactions of its compounds with organic substrates and reactive intermediates (e.g. benzino diazomethane) are reported. (C.L.B.) [pt

Sorption mechanisms of selenium species (selenite and selenate) on copper-based minerals; Mecanismes de sorption des especes du selenium (selenite et seleniate) sur des mineraux a base de cuivre

Energy Technology Data Exchange (ETDEWEB)

Devoy, J

2001-09-01

The sorption of radionuclides on the surface of minerals represents a process capable to delay the migration of the elements from a spent fuel deep repository towards the biosphere. In the framework of a deep underground repository, an engineered clay barrier has a high trapping capacity for cationic radio-elements, in particular because of the negative charge of clay surfaces. However, anionic radioelements like selenium species, would be only weakly retained by chemical processes. In order to optimize the trapping capacity of a clay barrier with respect to anionic species, prospective studies are carried out in order to find and evaluate some minerals with specific chemical trapping functions. Among radionuclides, the case of selenium has to be considered because its isotope {sup 79}Se is present in radioactive wastes and has a half life time of 6.5 10{sup 4} years. It is also judicious to find a mineral capable of trapping simultaneously several anionic radio-elements. Copper oxides and sulfides (Cu{sub 2}O, CuO, Cu{sub 2}S, CuS, CuFeS{sub 2} and Cu{sub 5}FeS{sub 4}) are good adsorbents with respect to selenium species (selenite and selenate). These minerals, with their selenium retention properties, could be used also for the decontamination of soils and waters or to process industrial effluents. The sorption mechanisms have been studied in details for copper oxides (Cu{sub 2}O and CuO) with respect to selenite and selenate. Chalcomenite precipitates in acid pH conditions when selenite is added to a Cu{sub 2}O and CuO suspension. Selenate, in contact with cuprite (Cu{sub 2}O) leads also to a selenium-based precipitate in acid pH environment. For higher pH values, selenite and selenate are adsorbed on copper oxides (Cu{sub 2}O and CuO) and lead to internal and external sphere complexes, respectively. In the case of a selenite/cuprite mixture in basic pH environment and at the equilibrium, a chemical reaction occurs between the oxidation product of cuprite, Cu

Approaches to achieve high grain yield and high resource use efficiency in rice

Directory of Open Access Journals (Sweden)

Jianchang YANG

2015-06-01

Full Text Available This article discusses approaches to simultaneously increase grain yield and resource use efficiency in rice. Breeding nitrogen efficient cultivars without sacrificing rice yield potential, improving grain fill in later-flowering inferior spikelets and enhancing harvest index are three important approaches to achieving the dual goal of high grain yield and high resource use efficiency. Deeper root distribution and higher leaf photosynthetic N use efficiency at lower N rates could be used as selection criteria to develop N-efficient cultivars. Enhancing sink activity through increasing sugar-spikelet ratio at the heading time and enhancing the conversion efficiency from sucrose to starch though increasing the ratio of abscisic acid to ethylene in grains during grain fill could effectively improve grain fill in inferior spikelets. Several practices, such as post-anthesis controlled soil drying, an alternate wetting and moderate soil drying regime during the whole growing season, and non-flooded straw mulching cultivation, could substantially increase grain yield and water use efficiency, mainly via enhanced remobilization of stored carbon from vegetative tissues to grains and improved harvest index. Further research is needed to understand synergistic interaction between water and N on crop and soil and the mechanism underlying high resource use efficiency in high-yielding rice.

Comprehensive efficiency analysis of supercomputer resource usage based on system monitoring data

Science.gov (United States)

Mamaeva, A. A.; Shaykhislamov, D. I.; Voevodin, Vad V.; Zhumatiy, S. A.

2018-03-01

One of the main problems of modern supercomputers is the low efficiency of their usage, which leads to the significant idle time of computational resources, and, in turn, to the decrease in speed of scientific research. This paper presents three approaches to study the efficiency of supercomputer resource usage based on monitoring data analysis. The first approach performs an analysis of computing resource utilization statistics, which allows to identify different typical classes of programs, to explore the structure of the supercomputer job flow and to track overall trends in the supercomputer behavior. The second approach is aimed specifically at analyzing off-the-shelf software packages and libraries installed on the supercomputer, since efficiency of their usage is becoming an increasingly important factor for the efficient functioning of the entire supercomputer. Within the third approach, abnormal jobs – jobs with abnormally inefficient behavior that differs significantly from the standard behavior of the overall supercomputer job flow – are being detected. For each approach, the results obtained in practice in the Supercomputer Center of Moscow State University are demonstrated.

Copper and selenium supplementation in the diet of Brangus steers on the nutritional characteristics of meat

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Arlindo Saran Netto

2013-01-01

Full Text Available Twenty-eight Brangus cattle were used to determine the effect of copper and selenium supplementation on the carcass characteristics, fatty acid composition of the longissimus dorsi muscle and on the copper and selenium concentrations in the liver. The treatments were: no supplementation of copper or selenium; 2 mg Se/kg DM as sodium selenite; 40 mg Cu/kg DM as copper sulfate; and 2 mg Se/kg DM as sodium selenite and 40 mg Cu/kg DM as copper sulfate. The fat thickness, rib eye area and fatty acid composition of the longissimus dorsi muscle were not affected by treatments. There was no effect on carcass yield and cooling loss with the supplementation of copper, selenium or selenium × copper in the levels studied. For the ether extract concentration in the longissimus dorsi muscle, no differences were found according to the treatments with selenium, copper or selenium × copper. The treatments with selenium and selenium × copper showed higher selenium concentrations in the liver than the control and copper treatments. For the copper concentration in the liver, the copper and selenium × copper treatments showed higher values than the control and selenium treatments. Despite the little effect on the meat composition, the results of this experiment demonstrate no interaction between selenium and copper in the levels studied.

Preliminary study of daily selenium level intake in algeria

International Nuclear Information System (INIS)

Benamar, M.A.; Tchantchane, A.; Tobbeche, S.

1992-10-01

The amount of selenium in onions and potatoes was measured by Pixe (particle Induced X-ray Emission) in the Nuclear Center at Bordeaux-Gradignan (CNBG). The goal of this work is to investigate the level of selenium concentration that may be consumed by different class of people

Product services for a resource-efficient and circular economy - A review

NARCIS (Netherlands)

Tukker, A.

2015-01-01

Since the 1990s, Product Service Systems (PSS) have been heralded as one of the most effective instruments for moving society towards a resource-efficient, circular economy and creating a much-needed 'resource revolution'. This paper reviews the literature on PSS in the last decade and compares the

Distribution and retention of inhaled selenium compounds in the rat

International Nuclear Information System (INIS)

Burkstaller, M.A.; Cuddihy, R.G.

1978-01-01

Selenium containing compounds released into the atmosphere during coal combustion are principally of the elemental form or the dioxide. These compounds differ greatly in their chemical properties. Fischer-344 rats were exposed via inhalation to both the dioxide and the red elemental form of selenium. Subsequently, measurements were made of internal absorption, organ distribution and retention, and modes of excretion. A radiotracer, 75 Se, was incorporated into the aerosol to facilitate these measurements. Retention of both aerosols in the total body showed long term components with half lives of 43 and 15 days accounting for 25 to 35% of the initially deposited selenium. Excretion occurred principally by way of urine. For both aerosols, selenium absorbed into the systemic circulation was mainly found in the liver, kidney, blood, gastrointestinal tract and bone

21 CFR 520.2100 - Selenium, vitamin E capsules.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Selenium, vitamin E capsules. 520.2100 Section 520... to 1 milligram of selenium) and 56.2 milligrams of vitamin E (68 I.U.) (as d-alpha tocopheryl acid... of vitamin E (17 I.U.) (as d-alpha tocopheryl acid succinate.) (b) Sponsor. See No. 000061 in § 510...

Comparison of pre-treatment and post-treatment use of selenium in retinal ischemia reperfusion injury

Directory of Open Access Journals (Sweden)

Alper Yazici

2015-04-01

Full Text Available AIM: To investigate the effects of selenium in rat retinal ischemia reperfusion (IR model and compare pre-treatment and post-treatment use. METHODS: Selenium pre-treatment group (n=8 was treated with intraperitoneal (i.p. selenium 0.5 mg/kg for 7d and terminated 24h after the IR injury. Selenium post-treatment group (n=8 was treated with i.p. selenium 0.5 mg/kg for 7d after the IR injury with termination at the end of the 7d period. Sham group (n=8 received i.p. saline injections identical to the selenium volume for 7d with termination 24h after the IR injury. Control group (n=8 received no intervention. Main outcome measures were retina superoxide dismutase (SOD, glutathione (GSH, total antioxidant status (TAS, malondialdehyde (MDA, DNA fragmentation levels, and immunohistological apoptosis evaluation. RESULTS: Compared to the Sham group, selenium pre-treatment had a statistical difference in all parameters except SOD. Post-treatment selenium also resulted in statistical differences in all parameters except the MDA levels. When comparing selenium groups, the pre-treatment selenium group had a statistically higher success in reduction of markers of cell damage such as MDA and DNA fragmentation. In contrast, the post-selenium treatment group had resulted in statistically higher levels of GSH. Histologically both selenium groups succeeded to limit retinal thickening and apoptosis. Pre-treatment use was statistically more successful in decreasing apoptosis in ganglion cell layer compared to post-treatment use. CONCLUSION: Selenium was successful in retinal protection in IR injuries. Pre-treatment efficacy was superior in terms of prevention of tissue damage and apoptosis.

Influence of Selenium on the Production of T-2 Toxin by Fusarium poae.

Science.gov (United States)

Cheng, Bolun; Zhang, Yan; Tong, Bei; Yin, Hong

2017-07-01

The objective of this study was to investigate the effects of selenium on the production of T-2 toxin by a Fusarium poae strain cultured in a synthetic medium containing different concentrations of selenium. The T-2 toxin contents in fermentative products were evaluated by a high performance liquid chromatography (HPLC). The results showed that the production of T-2 toxin was correlated with the concentration of selenium added to the medium. In all three treatments, the addition of 1 mg/L selenium to the medium resulted in a lower toxin yield than the control (0 mg/L); the yield of the toxin began to increase when selenium concentration was 10 mg/L, while it decreased again at 20 mg/L. In summary, T-2 toxin yield in the fermentative product was affected by the addition of selenium to the medium, and a selenium concentration of 20 mg/L produced the maximum inhibitory effect of T-2 toxin yield in the fermentative product of F. poae.

Effect of selenium-enriched organic material amendment on selenium fraction transformation and bioavailability in soil.

Science.gov (United States)

Wang, Dan; Dinh, Quang Toan; Anh Thu, Tran Thi; Zhou, Fei; Yang, Wenxiao; Wang, Mengke; Song, Weiwei; Liang, Dongli

2018-05-01

To exploit the plant byproducts from selenium (Se) biofortification and reduce environmental risk of inorganic Se fertilizer, pot experiment was conducted in this study. The effects of Se-enriched wheat (Triticum aestivum L.) straw (WS + Se) and pak choi (Brassica chinensis L.) (P + Se) amendment on organo-selenium speciation transformation in soil and its bioavailability was evaluated by pak choi uptake. The Se contents of the cultivated pak choi in treatments amended with the same amount of Se-enriched wheat straw and pak choi were 1.7 and 9.7 times in the shoots and 2.3 and 6.3 times in the roots compared with control treatment. Soil respiration rate was significantly increased after all organic material amendment in soil (p organic materials and thus resulted in soluble Se (SOL-Se), exchangeable Se (EX-Se), and fulvic acid-bound Se (FA-Se) fraction increasing by 25.2-29.2%, 9-13.8%, and 4.92-8.28%, respectively. In addition, both Pearson correlation and cluster analysis showed that EX-Se and FA-Se were better indicators for soil Se availability in organic material amendment soils. The Marquardt-Levenberg Model well described the dynamic kinetics of FA-Se content after Se-enriched organic material amendment in soil mainly because of the mineralization of organic carbon and organo-selenium. The utilization of Se in P + Se treatment was significantly higher than those in WS + Se treatment because of the different mineralization rates and the amount of FA-Se in soil. Se-enriched organic materials amendment can not only increase the availability of selenium in soil but also avoid the waste of valuable Se source. Copyright © 2018 Elsevier Ltd. All rights reserved.

Treating chronic arsenic toxicity with high selenium lentil diets

Energy Technology Data Exchange (ETDEWEB)

Sah, Shweta [Department of Ecosystem and Public Health, Faculty of Medicine, University of Calgary, Calgary, AB T2N 4Z6 (Canada); Vandenberg, Albert [Department of Plant Sciences, University of Saskatchewan, Saskatoon, SK S7N 5A8 (Canada); Smits, Judit, E-mail: judit.smits@ucalgary.ca [Department of Ecosystem and Public Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB T2N 4Z6 (Canada)

2013-10-01

Arsenic (As) toxicity causes serious health problems in humans, especially in the Indo-Gangetic plains and mountainous areas of China. Selenium (Se), an essential micronutrient is a potential mitigator of As toxicity due to its antioxidant and antagonistic properties. Selenium is seriously deficient in soils world-wide but is present at high, yet non-toxic levels in the great plains of North America. We evaluate the potential of dietary Se in counteracting chronic As toxicity in rats through serum biochemistry, blood glutathione levels, immunotoxicity (antibody response), liver peroxidative stress, thyroid response and As levels in tissues and excreta. To achieve this, we compare diets based on high-Se Saskatchewan (SK) lentils versus low-Se lentils from United States. Rats drank control (0 ppm As) or As (40 ppm As) water while consuming SK lentils (0.3 ppm Se) or northwestern USA lentils (< 0.01 ppm Se) diets for 14 weeks. Rats on high Se diets had higher glutathione levels regardless of As exposure, recovered antibody responses in As-exposed group, higher fecal and urinary As excretion and lower renal As residues. Selenium deficiency caused greater hepatic peroxidative damage in the As exposed animals. Thyroid hormones, triiodothyronine (T3) and thyroxine (T4), were not different. After 14 weeks of As exposure, health indicators in rats improved in response to the high Se lentil diets. Our results indicate that high Se lentils have a potential to mitigate As toxicity in laboratory mammals, which we hope will translate into benefits for As exposed humans. - Highlights: • We reduce chronic arsenic toxicity in rats with a whole food solution. • High selenium lentils decrease liver damage and increase blood glutathione levels. • High selenium lentil diets increase urinary and fecal arsenic excretion. • High selenium lentil diets decrease arsenic levels in kidney, the storage organ. • High selenium lentil diets reverse arsenic suppression of the B cell

Treating chronic arsenic toxicity with high selenium lentil diets

International Nuclear Information System (INIS)

Sah, Shweta; Vandenberg, Albert; Smits, Judit

2013-01-01

Arsenic (As) toxicity causes serious health problems in humans, especially in the Indo-Gangetic plains and mountainous areas of China. Selenium (Se), an essential micronutrient is a potential mitigator of As toxicity due to its antioxidant and antagonistic properties. Selenium is seriously deficient in soils world-wide but is present at high, yet non-toxic levels in the great plains of North America. We evaluate the potential of dietary Se in counteracting chronic As toxicity in rats through serum biochemistry, blood glutathione levels, immunotoxicity (antibody response), liver peroxidative stress, thyroid response and As levels in tissues and excreta. To achieve this, we compare diets based on high-Se Saskatchewan (SK) lentils versus low-Se lentils from United States. Rats drank control (0 ppm As) or As (40 ppm As) water while consuming SK lentils (0.3 ppm Se) or northwestern USA lentils (< 0.01 ppm Se) diets for 14 weeks. Rats on high Se diets had higher glutathione levels regardless of As exposure, recovered antibody responses in As-exposed group, higher fecal and urinary As excretion and lower renal As residues. Selenium deficiency caused greater hepatic peroxidative damage in the As exposed animals. Thyroid hormones, triiodothyronine (T3) and thyroxine (T4), were not different. After 14 weeks of As exposure, health indicators in rats improved in response to the high Se lentil diets. Our results indicate that high Se lentils have a potential to mitigate As toxicity in laboratory mammals, which we hope will translate into benefits for As exposed humans. - Highlights: • We reduce chronic arsenic toxicity in rats with a whole food solution. • High selenium lentils decrease liver damage and increase blood glutathione levels. • High selenium lentil diets increase urinary and fecal arsenic excretion. • High selenium lentil diets decrease arsenic levels in kidney, the storage organ. • High selenium lentil diets reverse arsenic suppression of the B cell

Selenium recovery from kiln powder of cement manufacturing by chemical leaching and bioreduction.

Science.gov (United States)

Soda, S; Hasegawa, A; Kuroda, M; Hanada, A; Yamashita, M; Ike, M

2015-01-01

A novel process by using chemical leaching followed by bacterial reductive precipitation was proposed for selenium recovery from kiln powder as a byproduct of cement manufacturing. The kiln powder at a slurry concentration of 10 w/v% with 0.25 M Na2CO3 at 28°C produced wastewater containing about 30 mg-Se/L selenium. The wastewater was diluted four-fold and adjusted to pH 8.0 as preconditioning for bioreduction. A bacterial strain Pseudomonas stutzeri NT-I, capable of reducing selenate and selenite into insoluble elemental selenium, could recover about 90% selenium from the preconditioned wastewater containing selenium of 5 mg-Se/L when supplemented with lactate or glycerol. The selenium concentrations in the treated wastewater were low around the regulated effluent concentration of 0.1 mg-Se/L in Japan.

Determination of molybdenum and selenium in bioenvironmental samples using neutron activation analysis

International Nuclear Information System (INIS)

Abu-Samra, A.; Morris, J.S.; Koirtyohann, S.R.; Vogt, J.R.

1974-01-01

Because of the increasing interest as to their roles in biological systems, a procedure has been developed by which molybdenum and selenium can be determined at nanogram levels in these types of samples. Results from the analysis of orchard leaves and bovine liver are presented. The samples are packaged in pre-cleaned quartz vials prepared from GE-204 tubing. If both selenium and molybdenum are to be determined, the samples are irradiated for 40 or more hours at a thermal neutron flux of 8 x 10 13 n cm -2 sec -1 . After the samples have decayed for approximately 48 hours the vials are unpackaged, cleaned in aqua-regia, and broken. The irradiation period can be reduced to 24 hours if molybdenum is to be determined individually or if the selenium content is known to be 1 microgram or more. The sample is digested with carriers and the selenium is then distilled as a volatile selenium halide. Elemental selenium is precipitated by reduction with SO 2 produced through the protonation of the hydrogen sulfite ion and subsequent decomposition of the resulting sulfurous acid. The 401 keV summation peak of 75 Se is normally used for quantitative determination. The chemical yield is determined by drying and weighing the elemental selenium

Production of selenium-72 and arsenic-72

Science.gov (United States)

Phillips, D.R.

1994-12-06

Methods and apparatus are described for producing selenium-72, separating it from its daughter isotope arsenic-72, and generating multiple portions of a solution containing arsenic-72 from a reusable parent substance comprised of selenium-72. The invention provides apparatus which can be located at a site where arsenic-72 is used, for purposes such as PET imaging, to produce arsenic-72 as needed, since the half-life of arsenic-72 is very short. 2 figures.

A composite efficiency metrics for evaluation of resource and energy utilization

International Nuclear Information System (INIS)

Yang, Siyu; Yang, Qingchun; Qian, Yu

2013-01-01

Polygeneration systems are commonly found in chemical and energy industry. These systems often involve chemical conversions and energy conversions. Studies of these systems are interdisciplinary, mainly involving fields of chemical engineering, energy engineering, environmental science, and economics. Each of these fields has developed an isolated index system different from the others. Analyses of polygeneration systems are therefore very likely to provide bias results with only the indexes from one field. This paper is motivated from this problem to develop a new composite efficiency metrics for polygeneration systems. This new metrics is based on the second law of thermodynamics, exergy theory. We introduce exergy cost for waste treatment as the energy penalty into conventional exergy efficiency. Using this new metrics could avoid the situation of spending too much energy for increasing production or paying production capacity for saving energy consumption. The composite metrics is studied on a simplified co-production process, syngas to methanol and electricity. The advantage of the new efficiency metrics is manifested by comparison with carbon element efficiency, energy efficiency, and exergy efficiency. Results show that the new metrics could give more rational analysis than the other indexes. - Highlights: • The composite efficiency metric gives the balanced evaluation of resource utilization and energy utilization. • This efficiency uses the exergy for waste treatment as the energy penalty. • This efficiency is applied on a simplified co-production process. • Results show that the composite metrics is better than energy efficiencies and resource efficiencies

Serum selenium concentration is associated with metabolic factors in the elderly: a cross-sectional study

Directory of Open Access Journals (Sweden)

Huang Hui-Ying

2010-05-01

Full Text Available Abstract Background Selenium is an essential micronutrient known for its antioxidant function. However, the association of serum selenium with lipid profiles and fasting glucose are inconsistent in populations with average intake of selenium. Furthermore, there were few studies conducted specifically for the elderly. This study examined the relationship of serum selenium concentration with serum lipids and fasting glucose in the Taiwanese elderly population. Methods This was a cross-sectional study of 200 males and females aged 65-85 years (mean 71.5 ± 4.6 years from Taipei, Taiwan. Serum selenium was measured by inductively coupled plasma-mass spectrometer. The association between serum selenium and metabolic factors was examined using a multivariate linear regression analysis after controlling several confounders. Results The mean serum selenium concentration was 1.14 μmol/L, without significant difference between sexes. Total cholesterol, triglycerides, and LDL cholesterol increased significantly with serum selenium concentration (P P P P Conclusions Total cholesterol, triglycerides, and LDL cholesterol, and fasting serum glucose concentrations increased significantly with serum selenium concentration in the Taiwanese elderly. The underlying mechanism warrants further research.

Relationship between soil contents and plasma levels of selenium ...

African Journals Online (AJOL)

The soil contents of trace elements selenium, chromium and manganese were measured to determine their impact on the plasma levels of 160 healthy adult Nigerians in five different experimental locations in Cross River and Akwa Ibom States, South - South Nigeria. The mean (±SD) soil selenium, chromium and ...

Low blood selenium: A probable factor in essential hypertension ...

African Journals Online (AJOL)

Blood selenium (BSe) and plasma glutathione peroxidase (plGSH-Px) activity were measured as biochemical markers of selenium status of 103 hypertensive patients (44 males and 59 females) and 88 apparently healthy subjects (40 males and 48 females). The hypertensive patients were classified into three groups based ...

Energy efficiency and integrated resource planning - lessons drawn from the Californian model

International Nuclear Information System (INIS)

Baudry, P.

2008-01-01

The principle of integrated resource planning (IRP) is to consider, on the same level, investments which aim to produce energy and those which enable energy requirements to be reduced. According to this principle, the energy efficiency programmes, which help to reduce energy demand and CO 2 emissions, are considered as an economically appreciated resource. The costs and gains of this resource are evaluated and compared to those relating to energy production. California has adopted an IRP since 1990 and ranks energy efficiency highest among the available energy resources, since economic evaluations show that the cost of realizing a saving of one kWh is lower than that which corresponds to its production. Yet this energy policy model is not universally widespread over the world. This can be explained by several reasons. Firstly, a reliable economic appreciation of energy savings presupposes that great uncertainties will be raised linked to the measurement of energy savings, which emanates in articular from the different possible options for the choice of base reference. This disinterest for IRP in Europe can also be explained by an institutional context of energy market liberalization which does not promote this type of regulation, as well as by the concern of making energy supply security the policies' top priority. Lastly, the remuneration of economic players investing in the energy efficiency programmes is an indispensable condition for its quantitative recognition in national investment planning. In France, the process of multi-annual investment programming is a mechanism which could lead to energy efficiency being included as a resource with economically appreciated investments. (author)

Efficient management of marine resources in conflict: an empirical study of marine sand mining, Korea.

Science.gov (United States)

Kim, Tae-Goun

2009-10-01

This article develops a dynamic model of efficient use of exhaustible marine sand resources in the context of marine mining externalities. The classical Hotelling extraction model is applied to sand mining in Ongjin, Korea and extended to include the estimated marginal external costs that mining imposes on marine fisheries. The socially efficient sand extraction plan is compared with the extraction paths suggested by scientific research. If marginal environmental costs are correctly estimated, the developed efficient extraction plan considering the resource rent may increase the social welfare and reduce the conflicts among the marine sand resource users. The empirical results are interpreted with an emphasis on guidelines for coastal resource management policy.

Effect of foliar application of selenium on its uptake and speciation in carrot

DEFF Research Database (Denmark)

Kápolna, Emese; Hillestrøm, Peter René; Laursen, K.H.

2009-01-01

Carrot (Daucus carota) shoots were enriched by selenium using foliar application. Solutions of sodium selenite or sodium selenate at 10 and 100 mu g Se ml(-1), were sprayed on the carrot leaves and the selenium content and uptake rate of selenium were estimated by ICP-MS analysis. Anion and cation......(-1) (dry mass) in the carrot root whereas the selenium concentration in the controls was below the limit of detection at 0.045 mu g Se g(-1) (dry mass). Selenate-enriched carrot leaves accumulated as much as 80 mu g Se g(-1) (dry mass), while the selenite-enriched leaves contained approximately 50 mu...... g Se g(-1) (dry mass). The speciation analyses showed that inorganic selenium was present in both roots and leaves. The predominant metabolised organic forms of selenium in the roots were selenomethionine and gamma-glutamyl-selenomethyl-selenocysteine, regardless of which of the inorganic species...

Effect of Se-enriched Organic Fertilizers on Selenium Accumulation in Corn and Soil

Directory of Open Access Journals (Sweden)

LI Sheng-nan

2015-12-01

Full Text Available The effect of two Se-enriched organic fertilizers (cow dung and rice straw biochar on selenium accumulation of corn growing in selenium deficient soil was studied with pot experiment. The results showed that corn accumulated more selenium and the selenium was much easier to convert from root to shoot in the corn plant with the application of Se-enriched cow dung than Se-enriched rice straw biochar. With the application of more organic fertilizer such as 25 t·hm-2 Se-enriched cow dung or 40 t·hm-2 Se-enriched rice straw biochar, the accumulation of selenium and growth status of corn were getting better than the other treatments. At the same time, as the application amount of Se-enriched organic fertilizers (cow dung and rice straw biochar increased, the total selenium content in the soil also increased, which positively correlated with each other.

Selenium. Role of the Essential Metalloid in Health

Science.gov (United States)

Kurokawa, Suguru; Berry, Marla J.

2015-01-01

Selenium is an essential micronutrient in mammals, but is also recognized as toxic in excess. It is a non-metal with properties that are intermediate between the chalcogen elements sulfur and tellurium. Selenium exerts its biological functions through selenoproteins. Selenoproteins contain selenium in the form of the 21st amino acid, selenocysteine (Sec), which is an analog of cysteine with the sulfur-containing side chain replaced by a Se-containing side chain. Sec is encoded by the codon UGA, which is one of three termination codons for mRNA translation in non-selenoprotein genes. Recognition of the UGA codon as a Sec insertion site instead of stop requires a Sec insertion sequence (SECIS) element in selenoprotein mRNAs and a unique selenocysteyl-tRNA, both of which are recognized by specialized protein factors. Unlike the 20 standard amino acids, Sec is biosynthesized from serine on its tRNA. Twenty-five selenoproteins are encoded in the human genome. Most of the selenoprotein genes were discovered by bioinformatics approaches, searching for SECIS elements downstream of in-frame UGA codons. Sec has been described as having stronger nucleophilic and electrophilic properties than cysteine, and Sec is present in the catalytic site of all selenoenzymes. Most selenoproteins, whose functions are known, are involved in redox systems and signaling pathways. However, several selenoproteins are not well characterized in terms of their function. The selenium field has grown dramatically in the last few decades, and research on selenium biology is providing extensive new information regarding its importance for human health. PMID:24470102

Polarographic determination of selenium and tellurium in silver-gold alloys

International Nuclear Information System (INIS)

Gornostaeva, T.D.; Shmargun, S.V.

1986-01-01

The determination of selenium and tellurium is of importance in monitoring the composition of silver-gold alloys (SGA) since these elements are harmful impurities in the pure metals. Tellurium is determined in silver alloys by atomic absorption and atomic emmission methods; selenium determination is made by atomic absorption methods. This paper examines the polarographic determination of silver and tellurium in SGA containing platinum metals and copper. Copper and the bulk of the platinum and palladium were removed by precipitating selenium and tellurium with potassium hypophosphite in the elementary state from 6 M HC1. The results of an analysis of samples of SGA according to the proposed method were compared with the results obtained by the atomic absorption method. the relative deviation in the determination of 0.02-1.0% by weight selenium and tellurium does not exceed 0.12 (n = 5)

Resource Use Efficiency Analysis for Potato Production in Nepal

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Mahesh Sapkota

2018-05-01

Full Text Available Potato is one of the most important staple foods supporting food security and livelihood to millions of marginalized and poor farmers in Nepal. Generally the smallholders’ farmers, especially those located in remote villages are inadequately informed about technical knowledge, inputs and efficient use of resources causing poor production and low productivity. Thus, the present survey aimed to examine the efficiency of resources used in potato production in Baglung District, one of the remote hilly place located in Central Himalaya. The total of 120 potato growing households was selected using simple random sampling technique from the two potato pocket in 2016. The regression coefficients of each inputs using Cobb-Douglas production function were estimated using Stata software. Our results showed that major inputs such as labor, bullock, Farm Yard Manure (FYM and intercultural operations were overused and need to decrease in terms of cost by 109, 177, 51 and 185%, respectively for its optimum allocation. Similarly, seed was found underused and need to increase its cost by 70% for optimum allocation. We concluded that inadequate training, exposure, knowledge gap and extension service to farmers in study sites were the reasons that farmers were using their resources inefficiently. It is recommended that the farmers involved in potato farming in the surveyed sites should be provided with additional proper technical knowledge for optimizing the use of resources which would help to increase the production and return from potato production.

Hypercholesterolemia and apolipoprotein B expression: Regulation by selenium status

Directory of Open Access Journals (Sweden)

Bansal Mohinder P

2005-11-01

Full Text Available Abstract Background Apolipoprotein B (apoB contains ligand-binding domain for the binding of LDL to LDL-R site, which enables the removal of LDL from circulation. Our recent data showed that selenium (Se is involved in the lipid metabolism. The present study was aimed to understand the effect of Se deficiency (0.02 ppm and selenium supplementation (1 ppm on apoB expression in liver during hypercholesterolemia in male Sprague Dawley rats. Animals were fed with control and high cholesterol diet (2% for 1 and 2 months. ApoB levels by ELISA and protein expression by western blot was done. Hepatic LDL receptor (LDL-R activity (in vivo and mRNA expression by RT-PCR was monitored. Results In selenium deficiency and on high cholesterol diet (HCD feeding apoB levels increased and LDL-R expression decreased significantly after 2 months. On 1 ppm selenium supplementation apoB expression significantly decreased and LDL-R expression increased after 2 months. But after one month of treatment there was no significant change observed in apoB and LDL-R expression. Conclusion So the present study demonstrates that Se deficiency leads to up regulation of apoB expression during experimental hypercholesterolemia. Selenium supplementation upto 1 ppm leads to downregulation of apoB expression. Further, this study will highlight the nutritional value of Se supplementation in lipid metabolism.

Profitability, Inputs Elasticities And Resource-Use Efficiency In Small ...

African Journals Online (AJOL)

The study examined profitability, inputs elasticities and resource-use efficiency in small scale cowpea production in Niger State, Nigeria. The primary data for the study were obtained using structured questionnaire administered to one hundred randomly sampled farmers from two Local Government Areas. Descriptive ...

Morphology and thermodynamic characteristics of selenium-containing nanostructures based on polymethacrylic acid

Science.gov (United States)

Valueva, S. V.; Borovikova, L. N.; Vylegzhanina, M. E.; Sukhanova, T. E.

2010-09-01

The morphology and thermodynamic characteristics of nanostructures formed as a result of the reduction of the selenium ion in a selenite-ascorbate redox system in water solutions of polymethacrylic acid were studied by molecular optics and atomic-force microscopy. The dependence of the morphology of the selenium-containing nanostructures on the mass selenium-to-polymer ratio (ν) in solution was determined. It was established that a large number of macromolecules (up to 4300) is adsorbed on the selenium nanoparticles, leading to the formation of nanostructures with super-high molecular mass and an almost spherical form. It was shown that the density of the nanostructures, as calculated on the basis of the experimental data on the size and molecular mass of the nanocomposite, depends substantially on the selenium concentrations in the solution. The thermodynamic state of the solutions of nanostructures is described.

Aquatic selenium pollution is a global environmental safety issue

Science.gov (United States)

A. Dennis Lemly

2004-01-01

Selenium pollution is a worldwide phenomenon and is associated with a broad spectrum of human activities, ranging from the most basic agricultural practices to the most high-tech industrial processes. Consequently, selenium contamination of aquatic habitats can take place in urban, suburban, and rural settings alike--from mountains to plains, from deserts to...

Enrichment of African catfish with functional selenium originating from garlic

NARCIS (Netherlands)

Schram, E.; Pedrero, Z.; Camara, C.; Heul, van der J.W.; Luten, J.B.

2008-01-01

We wanted to create functional seafood with high concentrations of organic selenium (seleno-methyl-selenocysteine and ¿-glutamyl-seleno-methyl-selenocysteine) with anti-carcinogenic properties for human consumers. Garlic containing high concentrations of these organic selenium compounds was used as

Selenium enrichment pattern in flowering Chinese cabbage, cabbage and asparagus

NARCIS (Netherlands)

Mo, H.Z.; Yang Zhu, Yang; Zhang, M.

2006-01-01

CONCLUSIONS - Within a certain range, selenium accumulation in three studied vegetables was lineally correlated with spraying concentration. However, a too high concentration caused the reduction of vegetable output and damage in quality. - Twice spraying with lower concentration of selenium was a

Cross sectional study of serum selenium concentration and esophageal squamous dysplasia in western Kenya.

Science.gov (United States)

Pritchett, Natalie R; Burgert, Stephen L; Murphy, Gwen A; Brockman, John D; White, Russell E; Lando, Justus; Chepkwony, Robert; Topazian, Mark D; Abnet, Christian C; Dawsey, Sanford M; Mwachiro, Michael M

2017-12-08

Low serum selenium status has been associated with increased risk of esophageal squamous cell carcinoma (ESCC). East Africa is a region of high ESCC incidence and is known to have low soil selenium levels, but this association has not previously been evaluated. In this study we assessed the association of serum selenium concentration and the prevalence of esophageal squamous dysplasia (ESD), the precursor lesion of ESCC, in a cross-sectional study of subjects from Bomet, Kenya. 294 asymptomatic adult residents of Bomet, Kenya completed questionnaires and underwent endoscopy with Lugol's iodine staining and biopsy for detection of ESD. Serum selenium concentrations were measured by instrumental neutron activation analysis. Odds ratios (OR) and confidence intervals (95% CI) for associations between serum selenium and ESD were calculated using unconditional logistic regression. The mean serum selenium concentration was 85.5 (±28.3) μg/L. Forty-two ESD cases were identified (14% of those screened), including 5 (12%) in selenium quartile 1 (Q1), 5 (12%) in Q2, 15 (36%) in Q3, and 17 (40%) in Q4. Higher serum selenium was associated with prevalence of ESD (Q4 vs Q1: OR: 3.03; 95% CI: 1.05-8.74) and this association remained after adjusting for potential confounders (Q4 vs Q1: OR: 3.87; 95% CI: 1.06-14.19). This is the first study to evaluate the association of serum selenium concentration and esophageal squamous dysplasia in an African population at high risk for ESCC. We found a positive association between higher serum selenium concentration and prevalence of ESD, an association contrary to our original hypothesis. Further work is needed to better understand the role of selenium in the etiology of ESCC in this region, and to develop effective ESCC prevention and control strategies.

The International Database of Efficient Appliances (IDEA): A New Resource for Global Efficiency Policy

Energy Technology Data Exchange (ETDEWEB)

Gerke, Brian F; McNeil, Michael A; Tu, Thomas; Xu, Feiyang

2017-09-06

A major barrier to effective appliance efficiency program design and evaluation is a lack of data for determination of market baselines and cost-effective energy savings potential. The data gap is particularly acute in developing countries, which may have the greatest savings potential per unit GDP. To address this need, we are developing the International Database of Efficient Appliances (IDEA), which automatically compiles data from a wide variety of online sources to create a unified repository of information on efficiency, price, and features for a wide range of energy-consuming products across global markets. This paper summarizes the database framework and demonstrates the power of IDEA as a resource for appliance efficiency research and policy development. Using IDEA data for refrigerators in China and India, we develop robust cost-effectiveness indicators that allow rapid determination of savings potential within each market, as well as comparison of that potential across markets and appliance types. We discuss implications for future energy efficiency policy development.

Neutron activation analysis applied to the determination of selenium in bovine plasma

International Nuclear Information System (INIS)

Hevia, Sonia E.; Resnizky, Sara M.; Gil, Susana B.; Pawlak, Eva

1999-01-01

The procedure used to determine selenium in bovine plasma by neutron irradiation of the samples, followed by a radiochemical separation, is described. This procedure allows the direct determination of the value of the selenium plasmatic level, instead of the indirect conventional method that determines the blood glutathion peroxidase enzyme, as an indicator of the selenium content in the blood. (author)

Mobilization of selenium from the Mancos Shale and associated soils in the lower Uncompahgre River Basin, Colorado

Science.gov (United States)

Mast, M. Alisa; Mills, Taylor J.; Paschke, Suzanne S.; Keith, Gabrielle; Linard, Joshua I.

2014-01-01

This study investigates processes controlling mobilization of selenium in the lower part of the Uncompahgre River Basin in western Colorado. Selenium occurs naturally in the underlying Mancos Shale and is leached to groundwater and surface water by limited natural runoff, agricultural and domestic irrigation, and leakage from irrigation canals. Soil and sediment samples from the study area were tested using sequential extractions to identify the forms of selenium present in solid phases. Selenium speciation was characterized for nonirrigated and irrigated soils from an agricultural site and sediments from a wetland formed by a leaking canal. In nonirrigated areas, selenium was present in highly soluble sodium salts and gypsum. In irrigated soils, soluble forms of selenium were depleted and most selenium was associated with organic matter that was stable under near-surface weathering conditions. Laboratory leaching experiments and geochemical modeling confirm that selenium primarily is released to groundwater and surface water by dissolution of highly soluble selenium-bearing salts and gypsum present in soils and bedrock. Rates of selenium dissolution determined from column leachate experiments indicate that selenium is released most rapidly when water is applied to previously nonirrigated soils and sediment. High concentrations of extractable nitrate also were found in nonirrigated soils and bedrock that appear to be partially derived from weathered organic matter from the shale rather than from agricultural sources. Once selenium is mobilized, dissolved nitrate derived from natural sources appears to inhibit the reduction of dissolved selenium leading to elevated concentrations of selenium in groundwater. A conceptual model of selenium weathering is presented and used to explain seasonal variations in the surface-water chemistry of Loutzenhizer Arroyo, a major tributary contributor of selenium to the lower Uncompahgre River.

Resource use efficiency and renewability. Assessment of low-input agricultural production using eMergy

DEFF Research Database (Denmark)

Wright, Christina; Østergård, Hanne

2014-01-01

by reducing dependency on external input. We apply the emergy approach to evaluate resource use efficiency of twolow-input innovative farms while distinguishing between use of renewable and non-renewable resources aswell as local and global origin of resources. This study is a part of the SOLIBAM (www.......solibam.eu) projectfunded by the European commission under the Seventh Framework Programme.We apply an approach where we include efficiency in resource use to produce food energy joules soldwhile distinguishing between use of renewable and non-renewable resources as well as on-site, local andnon-local resources. Result...... shows that the large farm (75 ha) had an input of renewable resources of 32%while the small (6 ha) had a renewable fraction of 26%. The latter is based on assuming that the firewoodused is 50% renewable. If this percentage is increased to 100% then both farms have a renewable fractionof resource use...

Efficiency in the European agricultural sector: environment and resources.

Science.gov (United States)

Moutinho, Victor; Madaleno, Mara; Macedo, Pedro; Robaina, Margarita; Marques, Carlos

2018-04-22

This article intends to compute agriculture technical efficiency scores of 27 European countries during the period 2005-2012, using both data envelopment analysis (DEA) and stochastic frontier analysis (SFA) with a generalized cross-entropy (GCE) approach, for comparison purposes. Afterwards, by using the scores as dependent variable, we apply quantile regressions using a set of possible influencing variables within the agricultural sector able to explain technical efficiency scores. Results allow us to conclude that although DEA and SFA are quite distinguishable methodologies, and despite attained results are different in terms of technical efficiency scores, both are able to identify analogously the worst and better countries. They also suggest that it is important to include resources productivity and subsidies in determining technical efficiency due to its positive and significant exerted influence.

On-line pre-reduction of Se(VI) by thiourea for selenium speciation by hydride generation

Energy Technology Data Exchange (ETDEWEB)

Qiu Jianhua [Department of Chemistry and the MOE Key Laboratory of Analytical Sciences, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005 (China); Wang Qiuquan [Department of Chemistry and the MOE Key Laboratory of Analytical Sciences, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005 (China)]. E-mail: qqwang@xmu.edu.cn; Ma Yuning [Department of Chemistry and the MOE Key Laboratory of Analytical Sciences, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005 (China); Yang Limin [Department of Chemistry and the MOE Key Laboratory of Analytical Sciences, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005 (China); Huang Benli [Department of Chemistry and the MOE Key Laboratory of Analytical Sciences, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005 (China)

2006-07-15

In this study, thiourea (TU) was novelly developed as a reduction reagent for on-line pre-reduction of selenium(VI) before conventional hydride generation (HG) by KBH{sub 4}/NaOH-HCl. After TU on-line pre-reduction, the HG efficiency of Se(VI) has been greatly improved and because even higher than that of the same amount of Se(IV) obtained in the conventional HG system. The possible pre-reduction mechanism is discussed. The detection limit (DL) of selenate reaches 10 pg mL{sup -1} when using on-line TU pre-reduction followed by HG atomic fluorescence detection. When TU pre-reduction followed by HG is used as an interface between ion-pair high performance liquid chromatography and atomic fluorescence spectrometry, selenocystine, selenomethionine, selenite and selenate can be measured simultaneously and quantitatively. The DLs of these are 0.06, 0.08, 0.05 and 0.04 ng mL{sup -1}, respectively, and the relative standard deviations of 9 duplicate runs for all the 4 species are less than 5%. Furthermore, it was successfully applied to Se speciation analysis of cultured garlic samples, and validated by determination of total selenium and selenium species in certified reference material NIST 1946.

Ultrathin high band gap solar cells with improved efficiencies from the world's oldest photovoltaic material.

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Todorov, Teodor K; Singh, Saurabh; Bishop, Douglas M; Gunawan, Oki; Lee, Yun Seog; Gershon, Talia S; Brew, Kevin W; Antunez, Priscilla D; Haight, Richard

2017-09-25

Selenium was used in the first solid state solar cell in 1883 and gave early insights into the photoelectric effect that inspired Einstein's Nobel Prize work; however, the latest efficiency milestone of 5.0% was more than 30 years ago. The recent surge of interest towards high-band gap absorbers for tandem applications led us to reconsider this attractive 1.95 eV material. Here, we show completely redesigned selenium devices with improved back and front interfaces optimized through combinatorial studies and demonstrate record open-circuit voltage (V OC ) of 970 mV and efficiency of 6.5% under 1 Sun. In addition, Se devices are air-stable, non-toxic, and extremely simple to fabricate. The absorber layer is only 100 nm thick, and can be processed at 200 ˚C, allowing temperature compatibility with most bottom substrates or sub-cells. We analyze device limitations and find significant potential for further improvement making selenium an attractive high-band-gap absorber for multi-junction device applications.Wide band gap semiconductors are important for the development of tandem photovoltaics. By introducing buffer layers at the front and rear side of solar cells based on selenium; Todorov et al., reduce interface recombination losses to achieve photoconversion efficiencies of 6.5%.

Selenium status, thyroid volume, and multiple nodule formation in an area with mild iodine deficiency

DEFF Research Database (Denmark)

Rasmussen, Lone Banke; Schomburg, Lutz; Kohrle, Josef

2011-01-01

) introduction of iodine fortification. Serum selenium concentration and urinary iodine were measured, and the thyroid gland was examined by ultrasonography in the same subjects. Associations between serum selenium concentration and thyroid parameters were examined in multiple linear regression models...... or logistic regression models.Results: Serum selenium concentration was found to be significantly, negatively associated with thyroid volume (P=0.006), and a low selenium status significantly increased the risk for thyroid enlargement (P=0.007). Furthermore, low serum selenium status had a tendency...

Biomarkers of selenium status

Science.gov (United States)

The essential trace element selenium (Se) has multiple biological activities, which depend on the level of Se intake. Relatively low Se intakes determine the expression of selenoenzymes in which it serves as an essential constituent. Higher intakes have been shown to have anti-tumorigenic potentia...

Selenium transformation in coal mine spoils: Its environmental impact assessment. Final report

Energy Technology Data Exchange (ETDEWEB)

Harness, J.; Atalay, A.; Koll, K.J.; Zhang, H.; Maggon, D.

1991-12-31

The objective of this program was to conduct an environmental impact assessment study for selenium from coal mine spoils. The use of in-situ lysimetry to predict selenium speciation, transformation, and mobility under natural conditions was evaluated. The scope of the study was to construct and test field-scale lysimeter and laboratory mini-column to assess mobility and speciation of selenium in coal mine overburden and soil systems; to conduct soil and groundwater sampling throughout the state of Oklahoma for an overall environmental impact assessment of selenium; and to conduct an in-depth literature review on the solubility, speciation, mobility, and toxicity of selenium from various sources. Groundwater and surface soil samples were also collected from each county in Oklahoma. Data collected from the lysimeter study indicated that selenium in the overburden of the abandoned mine site was mainly found in the selenite form. The amount of selenite found was too low and immobile to be of concern to the environment. The spoil had equilibrated long enough (over 50 years) that most of the soluble forms of selenium have already been lost. Examination of the overburden indicated the presence of pyrite crystals that precipitated over time. The laboratory mini-column study indicated that selenite is quite immobile and remained on the overburden material even after leaching with dilute acid. Data from groundwater samples indicated that based on the current permissible level for selenium in groundwater (0.01 mg Se/L), Oklahoma groundwater is widely contaminated with the element. However, according to the new regulation (0.05 mg Se/L), which is to be promulgated in 1992, only 9 of the 77 counties in the state exceed the limit.

Enhanced osteoblast adhesion on nanostructured selenium compacts for anti-cancer orthopedic applications

Directory of Open Access Journals (Sweden)

Phong Tran

2008-10-01

Full Text Available Phong Tran1, Thomas J Webster21Physics Department; 2Division of Engineering and Department of Orthopedics, Brown University, Providence, USAAbstract: Metallic bone implants possess numerous problems limiting their long-term efficacy, such as poor prolonged osseointegration, stress shielding, and corrosion under in vivo environments. Such problems are compounded for bone cancer patients since numerous patients receive orthopedic implants after cancerous bone resection. Unfortunately, current orthopedic materials were not originally developed to simultaneously increase healthy bone growth (as in traditional orthopedic implant applications while inhibiting cancerous bone growth. The long-term objective of the present research is to investigate the use of nano-rough selenium to prevent bone cancer from re-occurring while promoting healthy bone growth for this select group of cancer patients. Selenium is a well known anti-cancer chemical. However, what is not known is how healthy bone cells interact with selenium. To determine this, selenium, spherical or semispherical shots, were pressed into cylindrical compacts and these compacts were then etched using 1N NaOH to obtain various surface structures ranging from the micron, submicron to nano scales. Changes in surface chemistry were also analyzed. Through these etching techniques, results of this study showed that biologically inspired surface roughness values were created on selenium compacts to match that of natural bone roughness. Moreover, results showed that healthy bone cell adhesion increased with greater nanometer selenium roughness (more closely matching that of titanium. In this manner, this study suggests that nano-rough selenium should be further tested for orthopedic applications involving bone cancer treatment.Keywords: selenium, nano-rough, osteoblast, cancer, chemopreventive

Selenium poisoning of fish by coal ash wastewater in Herrington Lake, Kentucky.

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Lemly, A Dennis

2018-04-15

Selenium pollution from the E.W. Brown Electric Generating Station was investigated in Herrington Lake, KY. Coal ash wastewater is discharged as surface water overflow from ash disposal ponds into the lake via a National Pollutant Discharge Elimination System permit issued by the Kentucky Division of Water, but the permit does not restrict or limit the amount of selenium released. Unpermitted discharges occur from seeps and drainage through leaks in ash pond dams. Together, these discharges have resulted in selenium concentrations in water, sediment, benthic macroinvertebrates, and fish that are 2-9 times the level that is toxic for fish reproduction and survival. A large proportion (12.2%, or 25 times background) of juvenile largemouth bass (Micropterus salmoides, the only species examined) exhibited spinal and/or craniofacial malformations that are consistent with selenium poisoning. Teratogenic Deformity Index values indicated a 3.05% population-level impact on the bass fishery, with total selenium-induced mortality (including pre-swimup mortality) estimated to be in excess of 25% per year. These findings confirm that coal ash discharges into Herrington Lake are contributing selenium to the Lake that is poisoning fish. Copyright © 2017 Elsevier Inc. All rights reserved.

Resource-use efficiencies of three indigenous tree species planted in resource islands created by shrubs: implications for reforestation of subtropical degraded shrublands

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Nan Liu; Qinfeng Guo

2012-01-01

Shrub resource islands are characterized by resources accumulated shrubby areas surrounded by relative barren soils. This research aims to determine resource-use efficiency of native trees species planted on shrub resource islands, and to determine how the planted trees may influence the resource islands in degraded shrublands in South China. Shrub (Rhodomyrtus...

Efficient Radio Resource Allocation in a GSM and GPRS Cellular Network

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David Vannucci

2004-10-01

Full Text Available This paper investigates the effect of various radio resource allocation strategies in a GSM/GPRS cellular network. The most efficient resource allocation is analysed as a function of the proportion of circuit switched voice and packet switched data load. The Grade of Service and average packet delay is investigated as a function of the load, packet size and call duration. Additionally, the feasibility of using voice over Internet Protocol as opposed to circuit switched voice is investigated as a means to increase subscriber capacity per base station. The work is motivated firstly by the complexity of having both circuit switched and packet switched connectivity on GSM/GPRS mobile cellular system and secondly that an exclusively packet based access on GSM/GPRS has the potential to increase the efficiency of resource utilisation by suitably varying the channel allocation to exploit the characteristics of voice and data traffic.

Plasma Selenium Biomarkers in Low Income Black and White Americans from the Southeastern United States

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Hargreaves, Margaret K.; Liu, Jianguo; Buchowski, Maciej S.; Patel, Kushal A.; Larson, Celia O.; Schlundt, David G.; Kenerson, Donna M.; Hill, Kristina E.; Burk, Raymond F.; Blot, William J.

2014-01-01

Biomarkers of selenium are necessary for assessing selenium status in humans, since soil variation hinders estimation of selenium intake from foods. In this study, we measured the concentration of plasma selenium, selenoprotein P (SEPP1), and glutathione peroxidase (GPX3) activity and their interindividual differences in 383 low-income blacks and whites selected from a stratified random sample of adults aged 40–79 years, who were participating in a long-term cohort study in the southeastern United States (US). We assessed the utility of these biomarkers to determine differences in selenium status and their association with demographic, socio-economic, dietary, and other indicators. Dietary selenium intake was assessed using a validated food frequency questionnaire designed for the cohort, matched with region-specific food selenium content, and compared with the US Recommended Dietary Allowances (RDA) set at 55 µg/day. We found that SEPP1, a sensitive biomarker of selenium nutritional status, was significantly lower among blacks than whites (mean 4.4±1.1 vs. 4.7±1.0 mg/L, p = 0.006), with blacks less than half as likely to have highest vs. lowest quartile SEPP1 concentration (Odds Ratio (OR) 0.4, 95% Confidence Interval (CI) 0.2–0.8). The trend in a similar direction was observed for plasma selenium among blacks and whites, (mean 115±15.1 vs. 118±17.7 µg/L, p = 0.08), while GPX3 activity did not differ between blacks and whites (136±33.3 vs. 132±33.5 U/L, p = 0.320). Levels of the three biomarkers were not correlated with estimated dietary selenium intake, except for SEPP1 among 10% of participants with the lowest selenium intake (≤57 µg/day). The findings suggest that SEPP1 may be an effective biomarker of selenium status and disease risk in adults and that low selenium status may disproportionately affect black and white cohort participants. PMID:24465457

nteraction of nutrient resource and crop diversity on resource use efficiency in different cropping systems

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E azizi

2016-05-01

Full Text Available Introduction Conventional operations in fields, soil and water management are not efficient and loss of and damage to the environment are considerable (Lal, 2000. Crop diversity and understanding the complex interactions between environmental and socioeconomic factors are approaches to make better use of limited resources (Tengberg et al., 1998. The most diverse ecosystems have a higher production under environment stress conditions compared with ecosystems with low diversity due to the better efficiency in the use of water, radiation and nutrients (Hulugalle & al, 1986; Walker & Ogindo, 2003. Materials and Methods In order to investigate the effects of crop diversity and nutrient source on resource use efficiency, a split plot experiment was conducted based on complete randomized blocks with 3 replications at the Agricultural Research Station, the Ferdowsi University of Mashhad, Iran, during 2006 and 2007. The treatments included manure and chemical fertilizers as the main plots and intercropping of 3 soybean varieties (Williams, Sahar and Gorgan3, intercropping of 3 Millet species (common millet, foxtail millet and pearl millet, intercropping of millet, soybean and sesame (Sesamum indicum and intercropping of millet, sesame, fenugreek (Trigonella foenum-graecum and ajowan (Trachyspermum ammi as sub plots. Results and Discussion The results indicated that in the first year, intercropping of 3 Millet species and intercropping of millet, soybean and sesame showed the highest water use efficiency (WUE based on biological yield. In the second year, intercropping of 3 millet species showed the highest WUE based on biological yield. The highest concentrations of nitrogen, phosphorous and potassium in crop tissues were observed in intercropping of 3 soybean varieties and intercropping of millet, soybean and sesame. In the first year, intercropping of 3 soybean varieties showed the highest nutrient use efficiency (NUE. In the second year, intercropping

Selenium deficiency and pregnancy outcome in pregnant women with HIV in Lagos, Nigeria.

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Okunade, Kehinde S; Olowoselu, Olusola F; Osanyin, Gbemisola E; John-Olabode, Sarah; Akanmu, Sulaimon A; Anorlu, Rose I

2018-04-16

To investigate the prevalence of maternal selenium deficiency and its effects on pregnancy outcomes in pregnant women with HIV in Lagos, Nigeria. The present descriptive cross-sectional study enrolled women aged 15-49 years with HIV who were at 14-26 weeks of a singleton pregnancy and were attending Lagos University Teaching Hospital, Lagos, Nigeria, between August 1, 2016, and April 30, 2017. Participants were selected by consecutive sampling and baseline data were collected through interviews. Venous blood samples were obtained to measure selenium concentrations, and associations between low maternal selenium concentrations (defined as <0.89 μmol/L) and pregnancy outcomes were examined using bivariate and multivariate analysis. The final analysis included 113 patients; selenium deficiency was recorded in 23 (20.4%) patients. Women with selenium deficiency had an approximately eight-fold higher risk of preterm delivery (adjusted odds ratio 7.61, 95% confidence interval 4.37-18.89; P=0.031) and of delivering a term neonate with a low delivery weight (adjusted odds ratio 8.11, 95% confidence interval 3.27-17.22; P=0.012), compared with women with a normal selenium concentration. The prevalence of selenium deficiency among pregnant women with HIV in Lagos was relatively high. The significant associations observed between maternal selenium deficiency and adverse pregnancy outcomes could have implications for the future management of HIV in pregnancy. © 2018 International Federation of Gynecology and Obstetrics.

Blood selenium concentrations and enzyme activities related to glutathione metabolism in wild emperor geese

Science.gov (United States)

Franson, J. Christian; Hoffman, David J.; Schmutz, Joel A.

2002-01-01

In 1998, we collected blood samples from 63 emperor geese (Chen canagica) on their breeding grounds on the Yukon-Kuskokwim Delta (YKD) in western Alaska, USA. We studied the relationship between selenium concentrations in whole blood and the activities of glutathione peroxidase and glutathione reductase in plasma. Experimental studies have shown that plasma activities of these enzymes are useful biomarkers of selenium-induced oxidative stress, but little information is available on their relationship to selenium in the blood of wild birds. Adult female emperor geese incubating their eggs in mid-June had a higher mean concentration of selenium in their blood and a greater activity of glutathione peroxidase in their plasma than adult geese or goslings that were sampled during the adult flight feathermolting period in late July and early August. Glutathione peroxidase activity was positively correlated with the concentration of selenium in the blood of emperor geese, and the rate of increase relative to selenium was greater in goslings than in adults. The activity of glutathione reductase was greatest in the plasma of goslings and was greater in molting adults than incubating females but was not significantly correlated with selenium in the blood of adults or goslings. Incubating female emperor geese had high selenium concentrations in their blood, accompanied by increased glutathione peroxidase activity consistent with early oxidative stress. These findings indicate that further study of the effects of selenium exposure, particularly on reproductive success, is warranted in this species.

Radio protective effects of selenium on rats

International Nuclear Information System (INIS)

Bakir, A.; Alya, G

2005-11-01

Potential radio-protective effects of different selenium supplement concentrations of 4, 8, 15 and 30 ppm were evaluated in rats. Four groups of rats were administered different concentrations of selenium in drinking water for 30 days before irradiation starting from the ablactation which considered as day 0. The results showed that the sodium selenite of 4 ppm and 8 ppm enhance the 30-day survival of irradiated rats at 7 Gy ( sup 6 sup 0 Co source, whole body irradiation dose rate of 1 Gy x min sup - sup 1) compared to the control group. The mean cumulated probability of survival of rats was 69%+-6 (mean+-S.E.) and 77%+-6 in 4 and 8 ppm groups, respectively, versus 42%+-9 for control group (P<0.001). It was also indicated that sodium selenite with concentrations of 15 and 30 ppm had no significant reduction in mortality. The mean cumulated probability of survival of rats was 50%+-12 (P=0.39) and 49%+-14 (P=0.04), respectively. The toxic effects of selenium were observed at 15 ppm and 30 ppm, survivals after 30 days of selenium intake were 76% and 46%, respectively. It was concluded that 4 and 8 ppm sodium selenite have a radio-protective effect. 15 and 30 ppm sodium selenite had no radio-protective effects in rats, this may be due to a synergism of toxicity and radiation effects. (author)

Evaluation of Selenium Content of Plant Samples Collected from Indigenous Sources for Se-supplementation

International Nuclear Information System (INIS)

Mahmud, T.; Sosan, A.; Rehman, R.; Abbas, A.

2010-01-01

Selenium contents were evaluated in different plant species such as Canola (Brassica napus), Sunflower (Helianthus annus), Turmeric (Curcuma longa), Soyabean Seeds (Glycine max) and Akk (Calotropis procera) in order to access their possibility for Se-supplementation. The dry ash of bulb of Turmeric and seeds of Canola, Sunflower, and Soyabean were digested in concentrated HNO/sub 3/, HClO/sub 4/ and HCl to obtain selenium (IV). After adding different reagents, stable blue colored complex was formed. From this colored complex, selenium (IV) was determined by UV/visible spectrophotometer. This work was carried out in an attempt to obtain information concerning the amount of selenium present in different plants. It was observed that Akk is a good accumulator of selenium as it contains almost 30 mu g selenium per gram and can be used for different medicinal applications. (author)

Current Knowledge on the Importance of Selenium in Food for Living Organisms: A Review.

Science.gov (United States)

Kieliszek, Marek; Błażejak, Stanisław

2016-05-10

Selenium is one of the elements classified within the group of micronutrients which are necessary in trace amounts for the proper functioning of organisms. Selenium participates in the protection of cells against excess H₂O₂, in heavy metal detoxification, and regulation of the immune and reproductive systems as well. It also ensures the proper functioning of the thyroid gland. Selenium induces the occurrence of the selenoprotein synthesis process involved in the antioxidant defense mechanism of the organism. Recent years have brought much success in the studies on selenium. Anticarcinogenic properties of selenium against some cancers have been reported. Supplementation is increasingly becoming a solution to this problem. A large number of different supplementation methods are promoting studies in this area. Slight differences in the selenium content can result in excess or deficiency, therefore supplementation has to be done carefully and cautiously.

An Introduction to Testing Web Applications with twill and Selenium

CERN Document Server

Brown, Titus; Huggins, Jason

2007-01-01

This Short Cut is an introduction tobuilding automated web tests using twotools, twill and Selenium. twill is a simpleweb scripting language that can be usedto automate web tests, while Selenium isa web testing framework that runs in anybrowser and can be used to test complexweb sites that make extensive use ofJavaScript. The best way to use this Short Cut is torun through the examples. We expectthat within an hour you can start writingyour own functional tests in either twillor Selenium, and within a day you willunderstand most, if not all, of the possibilitiesand the limitations of these t

Toenail selenium level among healthy residents of two Polish Districts

International Nuclear Information System (INIS)

Zukowska, J.; Biziuk, M.; Bode, P.

2009-01-01

The goal of this study was to evaluate the selenium mass fraction in toenail clippings taken from random inhabitants living in various areas of the Pomeranian (Northern Poland) and Lubuskie (Western Poland) Districts. Toenail clippings were analyzed by instrumental neutron activation analysis (INAA) giving means of 0.57±0.10 and 0.60±0.16 mg x kg -1 for the two areas, respectively, but the difference was statistically not significant. In additional, it was found that gender, age, body mass index (BMI), smoking, and selenium supplementation are factors with apparent effects to the selenium levels in toenail clippings. (author)

Nanosized Selenium: A Novel Platform Technology to Prevent Bacterial Infections

Science.gov (United States)

Wang, Qi

As an important category of bacterial infections, healthcare-associated infections (HAIs) are considered an increasing threat to the safety and health of patients worldwide. HAIs lead to extended hospital stays, contribute to increased medical costs, and are a significant cause of morbidity and mortality. In the United States, infections encountered in the hospital or a health care facility affect more than 1.7 million patients, cost 35.7 billion to 45 billion, and contribute to 88,000 deaths in hospitals annually. The most conventional and widely accepted method to fight against bacterial infections is using antibiotics. However, because of the widespread and sometimes inappropriate use of antibiotics, many strains of bacteria have rapidly developed antibiotic resistance. Those new, stronger bacteria pose serious, worldwide threats to public health and welfare. In 2014, the World Health Organization (WHO) reported antibiotic resistance as a global serious threat that is no longer a prediction for the future but is now reality. It has the potential to affect anyone, of any age, in any country. The most effective strategy to prevent antibiotic resistance is minimizing the use of antibiotics. In recent years, nanomaterials have been investigated as one of the potential substitutes of antibiotics. As a result of their vastly increased ratio of surface area to volume, nanomaterials will likely exert a stronger interaction with bacteria which may affect bacterial growth and propagation. A major concern of most existing antibacterial nanomaterials, like silver nanoparticles, is their potential toxicity. But selenium is a non-metallic material and a required nutrition for the human body, which is recommended by the FDA at a 53 to 60 μg daily intake. Nanosized selenium is considered to be healthier and less toxic compared with many metal-based nanomaterials due to the generation of reactive oxygen species from metals, especially heavy metals. Therefore, the objectives of

Potential reproduction and response of selenium and zinc mineral supplementation on quality of goat samosir semen

Science.gov (United States)

Siswoyo, P.; Tafsin, M.; Handarini, R.

2018-02-01

The present study was conducted to investigate the effect of suppllementattion of selenium and zinc on semen quality and growth of samosir goat. The experimental design used latin square design (4x4). The treatment supplementation mineral on multi nutrient block (MNB) composed of without sipplementation (p0), +10ppm selenium (p1), +10ppm zinc (p2), +10ppm selenium and +10ppm zinc (p3). The result showed that supplementation mineral selenium and zinc increased significantly (pgoat were supplemented by selenium and zinc influenced motility, viability, volume concentration, and responding hypo osmotic swelling (HOS). Combination supplementation selenium and zinc significanly had higher semen quality than ither treatment. It is concluded that supplementation selenium and zinc improve growth and semen quality of samosir goat.

In vitro antioxidant and antiproliferative activities of selenium-containing phycocyanin from selenium-enriched Spirulina platensis.

Science.gov (United States)

Chen, Tianfeng; Wong, Yum-Shing

2008-06-25

Both selenium and phycocyanin have been reported to show potent cancer chemopreventive activities. In this study, we investigated the in vitro antioxidant and antiproliferative activities of selenium-containing phycocyanin (Se-PC) purified from selenium-enriched Spirulina platensis. The antioxidant activity of Se-PC was evaluated by using four different free radical scavenging assays, namely, the 2,2'-azinobis-3-ethylbenzothiazolin-6-sulfonic acid (ABTS) assay, 1,1-diphenyl-2-picryhydrazyl (DPPH) assay, superoxide anion scavenging assay, and erythrocyte hemolysis assay. The results indicated that Se-PC exhibited stronger antioxidant activity than phycocyanin by scavenging ABTS, DPPH, superoxide anion, and 2,2'-azobis-(2-amidinopropane)dihydrochloride free radicals. Se-PC also showed dose-dependent protective effects on erythrocytes against H 2O 2-induced oxidative DNA damage as evaluated by the Comet assay. Moreover, Se-PC was identified as a potent antiproliferative agent against human melanoma A375 cells and human breast adenocarcinoma MCF-7 cells. Induction of apoptosis in both A375 and MCF-7 cells by Se-PC was evidenced by accumulation of sub-G1 cell populations, DNA fragmentation, and nuclear condensation. Further investigation on intracellular mechanisms indicated that depletion of mitochondrial membrane potential (DeltaPsi m) was involved in Se-PC-induced cell apoptosis. Our findings suggest that Se-PC is a promising organic Se species with potential applications in cancer chemoprevention.

Characterisation of selenium compounds in rye seedling biomass using {sup 75}Se-labelling/SDS-PAGE separation/{gamma}-scintillation counting, and HPLC-ICP-MS analysis of a range of enzymatic digests

Energy Technology Data Exchange (ETDEWEB)

Bryszewska, Malgorzata A. [Technical University of Lodz (Poland). Institute of General Food Chemistry; Ambroziak, Wojciech [Technical University of Lodz (Poland). Institute of Fermentation Technology and Microbiology; Rudzinski, Juliusz [Technical University of Lodz (Poland). Institute of Applied Radiation Chemistry; Lewis, D. John [Central Science Laboratory, York (United Kingdom)

2005-07-01

In the present study, selenium-enriched plant biomass was investigated to evaluate the ability of rye seedlings to take up, and assimilate, inorganic selenium. Two different analytical approaches were used. Electrophoretic separation (SDS-PAGE) of proteins extracted from {sup 75}Se-labelled biomass was used to investigate the biotransformation of selenite into organic forms of the element. Ion-pair chromatography coupled with ICP-MS detection was chosen for the analysis of selenium species, enzymatically extracted from the plant biomass. The results of three enzymatic hydrolysis procedures and three sequential enzymatic extractions procedures are compared. The most effective single extraction was proteolysis (using protease type XIV), giving an overall extraction efficiency of 48%. However, for combinations of enzymes, the most effective was cellulase (Trichoderma viride) followed by sequential extraction of the solid pellet using protease type XIV, giving an extraction efficiency of 70%. The complementary data from the electrophoretic fractionation of proteins, and the HPLC separation of Se-species in the proteolytic digests, reveal the existence of large number of selenium-containing compounds in the rye seedling plant biomass. The results showed the complete biotransformation of inorganic selenium into organic forms during germination of the rye seedlings. HPLC-ICP-MS analysis of extracts from the plant biomass did not show the presence of selenate or selenite. At the time of this study, the lack of suitable organic-MS facilities meant that it was not possible to characterise them fully. However, the data does show that a combination of different enzymes, rather than just the commonly-used protease, should be considered when developing an extraction strategy for selenium in different food types to those already reported in the literature. (orig.)

Processing speed training increases the efficiency of attentional resource allocation in young adults

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Wesley K Burge

2013-10-01

Full Text Available Cognitive training has been shown to improve performance on a range of tasks. However, the mechanisms underlying these improvements are still unclear. Given the wide range of transfer effects, it is likely that these effects are due to a factor common to a wide range of tasks. One such factor is a participant’s efficiency in allocating limited cognitive resources. The impact of a cognitive training program, Processing Speed Training (PST, on the allocation of resources to a set of visual tasks was measured using pupillometry in 10 young adults as compared to a control group of a 10 young adults (n = 20. PST is a well-studied computerized training program that involves identifying simultaneously presented central and peripheral stimuli. As training progresses, the task becomes increasingly more difficult, by including peripheral distracting stimuli and decreasing the duration of stimulus presentation. Analysis of baseline data confirmed that pupil diameter reflected cognitive effort. After training, participants randomized to PST used fewer attentional resources to perform complex visual tasks as compared to the control group. These pupil diameter data indicated that PST appears to increase the efficiency of attentional resource allocation. Increases in cognitive efficiency have been hypothesized to underlie improvements following experience with action video games, and improved cognitive efficiency has been hypothesized to underlie the benefits of processing speed training in older adults. These data reveal that these training schemes may share a common underlying mechanism of increasing cognitive efficiency in younger adults.

Manganese and selenium concentrations in cerebrospinal fluid of seriously ill children.

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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.

Selenium and breast cancer risk: A prospective nested case-control study on serum selenium levels, smoking habits and overweight.

Science.gov (United States)

Sandsveden, Malte; Manjer, Jonas

2017-11-01

Previous research has not been conclusive regarding the association between selenium (Se) and breast cancer. This study was conducted to clarify if there is an association between prediagnostic serum Se levels and breast cancer risk. A population based cohort, the Malmö Diet and Cancer Study, was used and linked with the Swedish cancer registry up to 31 December 2013. Our study included 1,186 women with breast cancer and an equal number of controls. Selenium levels were analysed from stored serum samples. The included individuals were divided into quartiles based on Se value and we compared breast cancer cases with controls using logistic regression yielding odds ratios (OR) with 95% confidence intervals. Serum Se was also analysed as a continuous variable regarding breast cancer risk. The analyses were adjusted for established risk factors and stratified on smoking status and body mass index (BMI). When comparing the highest Se quartile with the lowest, the adjusted OR for breast cancer was 0.98 (0.75-1.26). With selenium as a continuous variable the adjusted OR was 1.00 (1.00-1.01) per 10 ng/ml. When comparing the highest with the lowest Se quartile in women with BMI > 25 kg/m 2 the adjusted OR was 0.77 (0.53-1.14). We conclude that it is unlikely that prediagnostic serum selenium is overall associated with breast cancer risk and no modifying effect from BMI or smoking was seen. © 2017 UICC.

Enrichment of meat products with selenium by its introduction to mixed feed compounds for birds

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А. Sobolev

2017-07-01

Full Text Available Selenium is a biologically active microelement, contained in a number of hormones and enzymes. In a bird or animal organism selenium performs the following functions: strengthens the immune system, stimulates formation of antibodies, macrophages and interferons. Also, it is a powerful antioxidant agent. It stimulates processes of metabolism in the organism, protects the organism against toxic manifestations of cadmium, lead, thalium and silver; stimulates reproductive function, decreases acute development of inflammatory processes; stabilizes functioning of the nervous system; normalizes functioning of the endocrine system. Furthermore, it stimulates synthesis of hemoglobin, takes part in secretion of erythrocutes, neutralizes toxins, prevents and stops development of malignant tumors. It also has a positive effect on the cardiovascular system of an animal organism: prevents myocardosis and decreases the risk of development of cardiovascular diseases. Deficiency of selenium in the organism causes (depending upon the extent of deficiency either physiological changes within the regulatory norm, significant disorders of the metabolism, or specific diseases. Around 75 different diseases and symptoms of pain are related to selenium deficiency. In most countries, the level of selenium consumption remains low (20–40 µg/day. There are several ways of improving of the selenium consumption of a population: consumption of selenium as a medication or dietary supplement, producing selenium-enriched bread, growing greens and vegetables rich in selenium, producing selenium-enriched beverages, products of animal origin, which would be rich in selenium. In the scientific-agricultural sphere studies have been made on the influence of adding different doses (0.2–0.6 mg/kg of selenium in mixed feeds and peculiarities of its depositing and distribution in the muscle tissues of young growth of different species of poultry. It has been found that feeding broiler

Selenium level in the environment and the population of Zhoukoudian area, Beijing, China

Energy Technology Data Exchange (ETDEWEB)

Li Na [Department of Epidemiology and Biostatistics, Peking University Health Science Center, 38 Xue Yuan Road, Hai, Dian District, Beijing 100083 (China); Gao Zhidong [Department of Epidemiology and Biostatistics, Peking University Health Science Center, 38 Xue Yuan Road, Hai, Dian District, Beijing 100083 (China); Luo Degang [Department of Epidemiology and Biostatistics, Peking University Health Science Center, 38 Xue Yuan Road, Hai, Dian District, Beijing 100083 (China); Tang Xun [Department of Epidemiology and Biostatistics, Peking University Health Science Center, 38 Xue Yuan Road, Hai, Dian District, Beijing 100083 (China); Chen Dafang [Department of Epidemiology and Biostatistics, Peking University Health Science Center, 38 Xue Yuan Road, Hai, Dian District, Beijing 100083 (China); Hu Yonghua [Department of Epidemiology and Biostatistics, Peking University Health Science Center, 38 Xue Yuan Road, Hai, Dian District, Beijing 100083 (China)]. E-mail: yhhu@bjmu.edu.cn

2007-08-01

The objective of this study was to detect the selenium level in the environment and the population of Zhoukoudian area, Beijing, and to discuss the influence of various factors on serum selenium level. The soil, drinking water, and foodstuff samples and venous blood samples of 401 individuals were obtained to determine the selenium level by gas chromatograph equipped with a {sup 63}Ni electron capture detector (ECD). The selenium level was 0.210 {+-} 0.013 {mu}g/g in soil, 0.017 {mu}g/L {+-} 0.002 in drinking water, 0.034 {+-} 0.002 {mu}g/g in rice, and 0.034 {+-} 0.012 {mu}g/g in wheat flour. This index showed that the Zhoukoudian area of Beijing was a moderate or marginal level selenium ecological landscape. The mean serum selenium level of the population was 75.01 {+-} 28.35 {mu}g/L, ranging between 35.2 and 160.4 {mu}g/L. A total of 279 (69.6%) individuals exhibited serum selenium level below 80 {mu}g/L, which is the lowest threshold for the activity of glutathione peroxidases (GPx) in vivo. A total of 35 (8.5%) individuals exhibited serum selenium level below 45 {mu}g/L. It is widely recommended that below this value (45 {mu}g/L) there is an increased risk of cardiovascular disease and cancer. Multiple linear regression analysis showed that serum selenium level was positively associated with body mass index ({beta} = 0.137; P = 0.011), serum total cholesterol TC ({beta} = 0.785; P = 0.000), however, negatively associated with systolic blood pressure ({beta} = - 0.172; P = 0.023), serum triglyceride ({beta} = - 0.170; P = 0.007), high density lipoprotein-cholesterol ({beta} = - 0.121; P = 0.027), and low high density lipoprotein-cholesterol ({beta} = - 0.568; P = 0.027)

Selenium level in the environment and the population of Zhoukoudian area, Beijing, China

International Nuclear Information System (INIS)

Li Na; Gao Zhidong; Luo Degang; Tang Xun; Chen Dafang; Hu Yonghua

2007-01-01

The objective of this study was to detect the selenium level in the environment and the population of Zhoukoudian area, Beijing, and to discuss the influence of various factors on serum selenium level. The soil, drinking water, and foodstuff samples and venous blood samples of 401 individuals were obtained to determine the selenium level by gas chromatograph equipped with a 63 Ni electron capture detector (ECD). The selenium level was 0.210 ± 0.013 μg/g in soil, 0.017 μg/L ± 0.002 in drinking water, 0.034 ± 0.002 μg/g in rice, and 0.034 ± 0.012 μg/g in wheat flour. This index showed that the Zhoukoudian area of Beijing was a moderate or marginal level selenium ecological landscape. The mean serum selenium level of the population was 75.01 ± 28.35 μg/L, ranging between 35.2 and 160.4 μg/L. A total of 279 (69.6%) individuals exhibited serum selenium level below 80 μg/L, which is the lowest threshold for the activity of glutathione peroxidases (GPx) in vivo. A total of 35 (8.5%) individuals exhibited serum selenium level below 45 μg/L. It is widely recommended that below this value (45 μg/L) there is an increased risk of cardiovascular disease and cancer. Multiple linear regression analysis showed that serum selenium level was positively associated with body mass index (β = 0.137; P = 0.011), serum total cholesterol TC (β = 0.785; P = 0.000), however, negatively associated with systolic blood pressure (β = - 0.172; P = 0.023), serum triglyceride (β = - 0.170; P = 0.007), high density lipoprotein-cholesterol (β = - 0.121; P = 0.027), and low high density lipoprotein-cholesterol (β = - 0.568; P = 0.027)

Selenium enrichment on Cordyceps militaris link and analysis on its main active components.

Science.gov (United States)

Dong, Jing Z; Lei, C; Ai, Xun R; Wang, Y

2012-03-01

To investigate the effects of selenium on the main active components of Cordyceps militaris fruit bodies, selenium-enriched cultivation of C. militaris and the main active components of the fruit bodies were studied. Superoxide dismutase (SOD) activity and contents of cordycepin, cordycepic acid, and organic selenium of fruit bodies were sodium selenite concentration dependent; contents of adenosine and cordycep polysaccharides were significantly enhanced by adding sodium selenite in the substrates, but not proportional to sodium selenite concentrations. In the cultivation of wheat substrate added with 18.0 ppm sodium selenite, SOD activity and contents of cordycepin, cordycepic acid, adenosine, cordycep polysaccharides, and total amino acids were enhanced by 121/145%, 124/74%, 325/520%, 130/284%, 121/145%, and 157/554%, respectively, compared to NS (non-selenium-cultivated) fruit bodies and wild Cordyceps sinensis; organic selenium contents of fruit bodies reached 6.49 mg/100 g. So selenium-enriched cultivation may be a potential way to produce more valuable medicinal food as a substitute for wild C. sinensis.

Marginal selenium deficiency down-regulates inflammation-related genes in splenic leukocytes of the mouse

NARCIS (Netherlands)

Kipp, A.P.; Banning, A.; Schothorst, van E.M.; Meplan, C.; Coort, S.L.; Evelo, C.; Keijer, J.; Hesketh, J.; Brigelius, R.

2012-01-01

Moderate selenium deficiency may lead to an impaired capacity to cope with health challenges. Functional effects of suboptimal selenium intake are not fully known, and biomarkers for an insufficient selenium supply are inadequate. We therefore fed mice diets of moderately deficient or adequate

Uptake and speciation of selenium in garlic cultivated in soil amended with symbiotic fungi (mycorrhiza) and selenate

DEFF Research Database (Denmark)

Larsen, Erik Huusfeldt; Lobinski, R.; Burger-Meyer, K.

2006-01-01

The scope of the work was to investigate the influence of selenate fertilisation and the addition of symbiotic fungi (mycorrhiza) to soil on selenium and selenium species concentrations in garlic. The selenium species were extracted from garlic cultivated in experimental plots by proteolytic...... in garlic. The selenium content in garlic, which was analysed by ICP-MS, showed that addition of mycorrhiza to the natural soil increased the selenium uptake by garlic tenfold to 15 mu g g(-1) (dry mass). Fertilisation with selenate and addition of mycorrhiza strongly increased the selenium content...... of soil by mycorrhiza and/or by selenate increased the content of selenium but not the distribution of detected selenium species in garlic. Finally, the use of two-dimensional HPLC (size exclusion followed by reversed-phase) allowed the structural characterisation of gamma...

Selenium homeostasis and induction of thioredoxin reductase during long term selenite supplementation in the rat

DEFF Research Database (Denmark)

Erkhembayar, Suvd; Mollbrink, Annelie; Eriksson, Malin

2011-01-01

-dependent increase in blood and liver selenium levels, with plateaus at 6 and 8weeks, respectively. These plateaus were reached at the same level of selenium regardless of dose, and no further accumulation was observed. A selenium-dependent increase in the activity of TrxR1 in parallel with the increase in liver...... selenium levels was also seen, and the induction of TrxR1 mRNA was seen only during the first three days of treatment, when the levels of selenium in the liver were increasing. Sodium selenite at 1 and 5μg/mL did not affect body weight or relative liver mass. We concluded that long-term treatment...... with selenite did not cause accumulation of selenium and that the activity of TrxR1 in the liver rose with the selenium levels. We therefore suggest that sodium selenite at doses up to 5μg/mL could be used for long-term tumour prevention....

Comparative effect of selenium and selenium tolerant microbes on brachiaria reptans l. growth

International Nuclear Information System (INIS)

Yasin, M.; Faisal, M.

2014-01-01

Brachiaria reptans L. is an annual grass. It is good fodder grass which is distributed in tropical Asia, Kenya, Pakistan and India and introduced throughout the tropics. In present study we determine the growth correlation among B. reptans, selenium (Se) and two Se tolerant bacteria (Bacillus licheniformis-YAP7 and Bacillus cereus-YAP6). Plants treated with Se showed a significant decrease in shoot length (33%) and fresh biomass (41%) compared to control. When plants were co-cultivated in the presence of bacteria or Se and bacteria both the shoot length increased (16-34%) significantly compared to control. B. reptans plants treated with Se have shown a significant decrease in peroxidase contents (59%) compared to control. However, bacterial inoculation of Se treated plants resulted in significant increase in peroxidase contents (113-171%). Selenium treatment caused increase in leaf soluble protein contents compared to control. In conclusion, bacteria can enhance B. reptans growth under Se stress. (author)

Determination of selenium in food matrices by replicate sample neutron activation analysis

International Nuclear Information System (INIS)

Ventura, M.G.; Freitas, M.C.; Ventura, M.G.; Pacheco, A.M.G.

2009-01-01

The replicate sample instrumental neutron activation method was optimized and used for the determination of selenium in foodstuffs. The method was reliable, yielding accurate results. Lower detections limits were obtained after each successive irradiation. Different irradiation conditions were used depending on the type of sample. For samples with higher selenium contents (meat, fish, eggs), the measured selenium in the first replicate is in all cases larger than the detection limit, but a better accuracy was obtained with a larger number of replicates (2-3 replicates). For samples with extremely low selenium contents (vegetable samples), at least seven replicates were necessary to obtain a concentration value two times larger than the detection limit. (author)

Selenium, selenoprotein genes and Crohn's disease in a case-control population from Auckland, New Zealand.

Science.gov (United States)

Gentschew, Liljana; Bishop, Karen S; Han, Dug Yeo; Morgan, Angharad R; Fraser, Alan G; Lam, Wen Jiun; Karunasinghe, Nishi; Campbell, Bobbi; Ferguson, Lynnette R

2012-09-01

New Zealand has one of the highest incidence rates of Crohn's Disease (CD), whilst the serum selenium status of New Zealanders is amongst the lowest in the world. A prospective case-control study in Auckland, New Zealand considered serum selenium as a potential CD risk factor. Serum selenium levels were significantly lower in CD patients compared to controls (101.8 ± 1.02 vs. 111.1 ± 1.01 ng/mL) (p = 5.91 × 10(-8)). Recent detailed studies in the United Kingdom have suggested an optimal serum level around 122 ng/mL, making the average CD patient in New Zealand selenium deficient. Of the 29 single nucleotide polymorphisms (SNPs) tested, 13 were found to significantly interact with serum selenium on CD. After adjustment for multiple testing, a significant interaction with serum selenium on CD was found for three SNPs, namely rs17529609 and rs7901303 in the gene SEPHS1, and rs1553153 in the gene SEPSECS. These three SNPs have not been reported elsewhere as being significantly associated with selenium or CD. It is unclear as to whether lower selenium levels are a cause or an effect of the disease.

Novel Machine Learning-Based Techniques for Efficient Resource Allocation in Next Generation Wireless Networks

KAUST Repository

AlQuerm, Ismail A.

2018-02-21

There is a large demand for applications of high data rates in wireless networks. These networks are becoming more complex and challenging to manage due to the heterogeneity of users and applications specifically in sophisticated networks such as the upcoming 5G. Energy efficiency in the future 5G network is one of the essential problems that needs consideration due to the interference and heterogeneity of the network topology. Smart resource allocation, environmental adaptivity, user-awareness and energy efficiency are essential features in the future networks. It is important to support these features at different networks topologies with various applications. Cognitive radio has been found to be the paradigm that is able to satisfy the above requirements. It is a very interdisciplinary topic that incorporates flexible system architectures, machine learning, context awareness and cooperative networking. Mitola’s vision about cognitive radio intended to build context-sensitive smart radios that are able to adapt to the wireless environment conditions while maintaining quality of service support for different applications. Artificial intelligence techniques including heuristics algorithms and machine learning are the shining tools that are employed to serve the new vision of cognitive radio. In addition, these techniques show a potential to be utilized in an efficient resource allocation for the upcoming 5G networks’ structures such as heterogeneous multi-tier 5G networks and heterogeneous cloud radio access networks due to their capability to allocate resources according to real-time data analytics. In this thesis, we study cognitive radio from a system point of view focusing closely on architectures, artificial intelligence techniques that can enable intelligent radio resource allocation and efficient radio parameters reconfiguration. We propose a modular cognitive resource management architecture, which facilitates a development of flexible control for

Examination of the selenium content of wheat grasses produced in different soil types in Csik Basin

Directory of Open Access Journals (Sweden)

Tamás M.

2015-01-01

Full Text Available In the course of the research, we determined selenium and dry matter content of 35 wheat grass and 35 wheat seed samples. The selenium content of the preparation plant probes was measured by spectrofluorimetric determination (λexcitation = 380 nm, λemission = 519 nm of the resulted piazselenol complex. It was established that between the selenium content of the wheat grass and wheat seed the correlation coefficient was 0.36 at p = 0.05 level, which indicates a medium-close correlation. Similarly, there was a medium-close correlation between the selenium content of the wheat grass calculated on dry-matter basis and total selenium content of the wheat, with a correlation coefficient of 0.40 at p = 0.02 level. Afterwards, beside the selenium content, we measured the selenomethionine content by ion-exchange chromatography and highperformance liquid chromatography, and the organic selenium content was calculated. A very close correlation was established between the total selenium, selenomethionine and calculated organic selenium content of wheat (the correlation coefficients were between 0.92 and 0.99 at p = 0.01 level. The correlation between the selenomethionine content of wheat grass and wheat seed was very weak (r = 0.23.

Epigenetic Regulation of Inflammatory Gene Expression in Macrophages by Selenium

Science.gov (United States)

Narayan, Vivek; Ravindra, Kodihalli C.; Liao, Chang; Kaushal, Naveen; Carlson, Bradley A.; Prabhu, K. Sandeep

2014-01-01

Acetylation of histone and non-histone proteins by histone acetyltransferases plays a pivotal role in the expression of pro-inflammatory genes. Given the importance of dietary selenium in mitigating inflammation, we hypothesized that selenium supplementation may regulate inflammatory gene expression at the epigenetic level. The effect of selenium towards histone acetylation was examined in both in vitro and in vivo models of inflammation by chromatin immunoprecipitation (ChIP) assays and immunoblotting. Our results indicated that selenium supplementation, as selenite, decreased acetylation of histone H4 at K12 and K16 in COX-2 and TNF promoters, and of the p65 subunit of the redox sensitive transcription factor NFκB in primary and immortalized macrophages. On the other hand, selenomethionine had a much weaker effect. Selenite treatment of HIV-1 infected human monocytes also significantly decreased the acetylation of H4 at K12 and K16 on the HIV-1 promoter, supporting the downregulation of proviral expression by selenium. A similar decrease in histone acetylation was also seen in the colonic extracts of mice treated with dextran sodium sulfate that correlated well with the levels of selenium in the diet. Bone marrow-derived macrophages from Trspfl/flCreLysM mice that lack expression of selenoproteins in macrophages confirmed the important role of selenoproteins in the inhibition of histone H4 acetylation. Our studies suggest that the ability of selenoproteins to skew the metabolism of arachidonic acid to contribute, in part, to their ability to inhibit histone acetylation. In summary, our studies suggest a new role for selenoproteins in the epigenetic modulation of pro-inflammatory genes. PMID:25458528

Reduction of selenite by Azospirillum brasilense with the formation of selenium nanoparticles.

Science.gov (United States)

Tugarova, Anna V; Vetchinkina, Elena P; Loshchinina, Ekaterina A; Burov, Andrei M; Nikitina, Valentina E; Kamnev, Alexander A

2014-10-01

The ability to reduce selenite (SeO(3)(2-)) ions with the formation of selenium nanoparticles was demonstrated in Azospirillum brasilense for the first time. The influence of selenite ions on the growth of A. brasilense Sp7 and Sp245, two widely studied wild-type strains, was investigated. Growth of cultures on both liquid and solid (2 % agar) media in the presence of SeO(3)(2-) was found to be accompanied by the appearance of the typical red colouration. By means of transmission electron microscopy (TEM), electron energy loss spectroscopy (EELS) and X-ray fluorescence analysis (XFA), intracellular accumulation of elementary selenium in the form of nanoparticles (50 to 400 nm in diameter) was demonstrated for both strains. The proposed mechanism of selenite-to-selenium (0) reduction could involve SeO(3)(2-) in the denitrification process, which has been well studied in azospirilla, rather than a selenite detoxification strategy. The results obtained point to the possibility of using Azospirillum strains as endophytic or rhizospheric bacteria to assist phytoremediation of, and cereal cultivation on, selenium-contaminated soils. The ability of A. brasilense to synthesise selenium nanoparticles may be of interest to nanobiotechnology for "green synthesis" of bioavailable amorphous red selenium nanostructures.

Sulfur and selenium isotope separation by distillation

International Nuclear Information System (INIS)

Mills, T. R.; McInteer, B. B.; Montoya, J. G.

1988-01-01

Sulfur and selenium isotopes are used for labeled compounds and as precursors for radioisotope production; however, both limited availability and high costs are problems. A new method is needed for large-scale separation of these isotopes. Experimental distillation columns were used to measure isotopic separations for sulfur and selenium compounds. The maximum total isotope separation of 32 S vs. 34 S were 1.127 for H 2 S, 1.048 for COS, 0.838 for SF 4 , and 1.058 for CH 3 SH. Relative volatilities of 32 S vs. 34 S are 1.0006 for COS and 0.9976 for SF 4 . There is a reverse isotope effect for carbon in COS. No isotopic separation was observed for dimethyl selenide. The lower mass selenium isotopes in H 2 Se are more volatile. Distillation is a promising method for separating sulfur isotopes on a production scale. Existing distillation technology produced separated isotopes with an effect similar to that found for sulfur in SF 4 . 8 refs., 2 tabs

Sulfur and selenium isotope separation by distillation

International Nuclear Information System (INIS)

Mills, T.R.; McInteer, B.B.; Montoya, J.G.

1989-01-01

Sulfur and selenium isotopes are used for labeled compounds and as precursors for radioisotope production; however, both limited availability and high costs are problems. A new method is needed for large-scale separation of theses isotopes. Experimental distillation columns were used to measure isotopic separations for sulfur and selenium compounds. The maximum total isotope separations of 32 S vs. 34 S were 1.127 for H 2 S, 1.048 for COS, 0.838 for SF 4 , and 1.058 for CH 3 SH. Relative volatilities of 32 S and 34 S are 1.0006 for COS and 0.9976 for SF 4 . There is a reverse isotope effect for carbon in COS. No isotopic separation was observed for dimethyl selenide. The lower mass selenium isotopes in H 2 Se are more volatile. Distillation is a promising method for separating sulfur isotopes on a production scale. Existing distillation technology produces separated isotopes with an effect similar to that found for sulfur in SF 4 . (author). 8 refs.; 2 tabs

Direct solution-phase synthesis of Se submicrotubes using Se powder as selenium source

International Nuclear Information System (INIS)

Yan Shancheng; Wang Haitao; Zhang Yuping; Li Shuchun; Xiao Zhongdang

2009-01-01

The selenium submicrotubes were directly prepared using Se powder as selenium source by microwave-assisted method. Field-emission scan electron microscopy (FESEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD) were adopted to characterize the as-prepared products. The results of high-resolution transmission electron microscopy (HRTEM) and XRD pattern proved that the selenium submicrotubes were single crystalline in nature and [0 0 1] oriented. A possible growth mechanism of the selenium submicrotubes was proposed. The effects of the experimental conditions, such as alkaline concentration and solvent properties, on the morphology and dimension of the products have also been discussed

Structure of amorphous selenium studied by neutron diffraction

DEFF Research Database (Denmark)

Hansen, Flemming Yssing; Knudsen, Torben Steen; Carneiro, K.

1975-01-01

Neutron diffraction measurements on amorphous selenium have been performed at 293 and 80 K. Careful analyses of the instrumental corrections were made to avoid systematic errors in the measured structure factor S (kappa) in the wave vector region 0 ? kappa ? 12 Å−1. As a result of the data...... treatment, the neutron scattering cross sections of selenium are determined to be sigmacoh = 8.4±0.1 b and sigmainc = 0.1±0.1 b. Using the fact that S (kappa) for large kappa's is determined by the short distances in the sample, a new method for extrapolation of the experimental S (kappa) until convergence....... Finally, we give a brief discussion of the different models for the structure of amorphous selenium, taking both diffraction measurements and thermodynamic considerations into account. The Journal of Chemical Physics is copyrighted by The American Institute of Physics....

EFFICIENCY OF THE USE OF AUTHENTIC WEB-RESOURCES IN TRANSLATORS TRAINING

Directory of Open Access Journals (Sweden)

Iryna M. Drobit

2013-06-01

Full Text Available The article deals with pedagogical assumptions and efficiency of the use of Information and Communication Technologies, especially authentic web-resources, while teaching language for specific purposes (translators and interpreters. Accuracy, content, and functionality of web-resource TED, which contains examples of authentic speech in English, have been outlined. It has been demonstrated that usage of multimedia and communication facilities of the TED web-resource provides favourable opportunity to involve students in such professional activities as translation and proofreading, and also to improve the level of their language skills.

Green synthesis of selenium nanoparticles by excimer pulsed laser ablation in water

OpenAIRE

O. Van Overschelde; G. Guisbiers; R. Snyders

2013-01-01

Pure selenium nanoparticles were successfully synthesized by Liquid Phase - Pulsed Laser Ablation (LP-PLA) in de-ionized water. Excimer laser (248 nm) operating at low fluence (F ∼ 1 J/cm2) was used to generate colloidal solutions of selenium nanoparticles. The obtained selenium nanoparticles were characterized by UV-visible spectroscopy, Raman spectroscopy, Dynamic Light Scattering, and Transmission Electron Microscopy. We describe the multi-modal size distributions generated and use the cen...

INFLUENCE OF DIETARY SELENIUM SUPPLEMENTATION OF EWES ON PRODUCTION TRAITS, ANTIOXIDANT STATUS AND METABOLIC PROFILE OF LAMBS

Directory of Open Access Journals (Sweden)

Josip Novoselec

2013-12-01

Full Text Available The aim of this study was to determine the effect of dietary selenium supplementation (organic, inorganic of high pregnant ewes on the production traits of lambs, the concentration of selenium in the blood of ewes and their lambs, indicators of antioxidant status in the blood of ewes and their lambs, the metabolic profile of ewes and their lambs and concentrations of thyroid hormones. Ewes were in the last third of pregnancy, the average age of four years, healthy and in good condition, divided into three groups of 10 animals. The research lasted 4 months respectively, 2 months with ewes during high pregnancy, 2 months with ewes during lactation and on their lambs during suckling period. Ewes ration from control group one was composed from 300 g/day/animal feed mixture without addition of selenium and 150 g/day/animal barley and alfalfa hay that they had ad libitum. Feed mixture from second group of ewes was supplemented with 0.3 mg/kg organic form of selenium (Sel-Plex®, and feed mixture from third group with the same amount inorganic form of selenium (sodium selenite. Selenium supplementation of ewes feed mixture did not significantly influence on the production traits of their lambs postpartum. Selenium supplementation of ewes and their lambs had influence on a significant (P<0.01; P<0.05 increase in the concentration of selenium, GSH-Px and SOD in whole blood compared to control group of ewes. Organic selenium supplement had a more significant impact on the increase in concentration of selenium and GSH-Px in the blood. In the ewes and lambs blood was determined decrease of MDA with increasing concentrations of selenium in the blood. Generally, the selenium supplementation led to an increase (P<0.05 in the number of WBC and lymphocytes in the blood of ewes and lambs. Also, the increase in the number of RBC, HGB content and MCV in lambs and MCH as well as MCHC in ewes that had a selenium supplement in feed mixture were determined

Serum selenium concentration in maternal and umbilical cord blood. Relation to course and outcome of pregnancy

DEFF Research Database (Denmark)

Bro, S; Berendtsen, H; Nørgaard, J

1988-01-01

The present knowledge of the role of selenium in human fetal and neonatal development is sparse. In this study we measured serum selenium concentrations in maternal and umbilical cord blood from 500 Danish mothers at delivery, looking for a relationship between various maternal and fetal complica......The present knowledge of the role of selenium in human fetal and neonatal development is sparse. In this study we measured serum selenium concentrations in maternal and umbilical cord blood from 500 Danish mothers at delivery, looking for a relationship between various maternal and fetal...... complications and selenium values. In mothers with uncomplicated pregnancies and deliveries serum selenium concentrations were 0.84 +/- 0.19 mumol/l (mean +/- SD), whereas in cord blood from full-term babies born adequate for gestational age and with no malformations serum selenium concentrations were 0...

Selenium bioavailability from naturally produced high-selenium peas and oats in selenium-deficient rats.

Science.gov (United States)

Yan, Lin; Johnson, LuAnn K

2011-06-08

This study determined the bioavailability of selenium (Se) from yellow peas and oats harvested from the high-Se soil of South Dakota, United States. The Se concentrations were 13.5 ± 0.2 and 2.5 ± 0.1 mg/kg (dry weight) for peas and oats, respectively. Male weanling Sprague-Dawley rats were depleted of Se by feeding them a 30% Torula yeast-based diet (4.1 μg Se/kg) for 56 days, and then they were replenished with Se for an additional 50 days by feeding them the same diet supplemented with 20, 30, or 40 μg Se/kg from peas or oats, respectively. Selenium bioavailability was determined on the basis of the restoration of Se-dependent enzyme activities and tissue Se concentrations in Se-depleted rats, comparing those responses for yellow peas and oats to those for l-selenomethionine (SeMet; used as a reference) by using a slope-ratio method. Dietary supplementation with peas or oats resulted in linear or log-linear, dose-dependent increases in glutathione peroxidase activities in blood and liver and in thioredoxin reductase activity in liver. Supplementation with peas or oats resulted in linear or log-linear, dose-dependent increases in Se concentrations of plasma, liver, gastrocnemius muscle, and kidneys. The overall bioavailability was approximately 88% for Se from yellow peas and 92% from oats, compared to SeMet. It was concluded that Se from naturally produced high-Se yellow peas or oats is highly bioavailable in this model and that these high-Se foods may be a good dietary source of Se.

Profitability And Resource Use Efficiency In Dry Season Onion ...

African Journals Online (AJOL)

The study evaluated profitability and resource use efficiency in dry season onion production in Sokoto and Kebbi States. Eight local government areas (L. G. As), four from each State, were purposively selected for the study. From each L.G.A., four villages were selected and from each village, five dry season onion farmers ...

Resource Use Efficiency in Rice Production in Jere Local ...

African Journals Online (AJOL)

The study was carried-out on resource use efficiency in rice production in Jere Local Government Area of Borno State, Nigeria. Data were obtained using structured questionnaire. Five (5) wards were purposely selected out of the twelve (12) wards to reflect areas where rice is mainly grown. A total of 100 respondents were ...

Effect of dietary selenium and omega-3 fatty acids on muscle composition and quality in broilers

Directory of Open Access Journals (Sweden)

Hetland Harald

2007-10-01

Full Text Available Abstract Background Human health may be improved if dietary intakes of selenium and omega-3 fatty acids are increased. Consumption of broiler meat is increasing, and the meat content of selenium and omega-3 fatty acids are affected by the composition of broiler feed. A two-way analyses of variance was used to study the effect of feed containing omega-3 rich plant oils and selenium enriched yeast on broiler meat composition, antioxidation- and sensory parameters. Four different wheat-based dietary treatments supplemented with 5% rapeseed oil or 4% rapeseed oil plus 1% linseed oil, and either 0.50 mg selenium or 0.84 mg selenium (organic form per kg diet was fed to newly hatched broilers for 22 days. Results The different dietary treatments gave distinct different concentrations of selenium and fatty acids in thigh muscle; one percent linseed oil in the diet increased the concentration of the omega-3 fatty acids 18:3, 20:5 and 22:5, and 0.84 mg selenium per kg diet gave muscle selenium concentration at the same level as is in fish muscle (0.39 mg/kg muscle. The high selenium intake also resulted in increased concentration of the long-chain omega-3 fatty acids EPA (20:5, DPA (22:5 and DHA (22:6, thus it may be speculated if high dietary selenium might have a role in increasing the concentration of EPA, DPA and DHA in tissues after intake of plant oils contning omega-3 fatty acids. Conclusion Moderate modifications of broiler feed may give a healthier broiler meat, having increased content of selenium and omega-3 fatty acids. High intakes of selenium (organic form may increase the concentration of very long-chain omega-3 fatty acids in muscle.

Accumulation of selenium in aquatic systems downstream of a uranium mining operation in northern Saskatchewan, Canada

International Nuclear Information System (INIS)

Muscatello, J.R.; Belknap, A.M.; Janz, D.M.

2008-01-01

The objective of this study was to investigate the accumulation of selenium in lakes downstream of a uranium mine operation in northern Saskatchewan, Canada. Selenium concentrations in sediment and biota were elevated in exposure areas even though water concentrations were low (<5 μg/L). The pattern (from smallest to largest) of selenium accumulation was: periphyton < plankton and filterer invertebrates < detritivore and predator invertebrates < small bodied (forage) fish and predatory fish. Biomagnification of selenium resulted in an approximately 1.5-6 fold increase in the selenium content between plankton, invertebrates and forage fish. However, no biomagnification was observed between forage fish and predatory fish. Selenium content in organisms from exposure areas exceeded the proposed 3-11 μg/g (dry weight) dietary toxicity threshold for fish, suggesting that the selenium released into these aquatic systems has the potential to bioaccumulate and reach levels that could impair fish reproduction. - Selenium bioaccumulation patterns in a north temperate, cold water aquatic ecosystem were similar to those reported from warm water systems

Relationship of dietary intake of fish and non-fish selenium to serum lipids in Japanese rural coastal community.

Science.gov (United States)

Miyazaki, Yukiko; Koyama, Hiroshi; Nojiri, Masami; Suzuki, Shosuke

2002-01-01

Several studies have suggested that dietary selenium deficiency may be associated with an increased risk of coronary heart disease (CHD). In the present study, 55 men and 71 women were selected from participants in a health examination in a rural coastal community in Japan. The mean dietary selenium intake calculated from the simple food frequency questionnaire (SFFQ) was 127.5 micrograms/day. Fish was the major source of dietary selenium and it contributed to 68.7% of the daily total. HDL cholesterol was higher in the middle selenium intake group and in the high selenium intake group than in the low selenium intake group in all subjects and for males, and a significant difference was found between the middle selenium intake group and the low selenium intake group. The atherogenic index was significantly higher in the low selenium intake group than in the middle selenium intake group and in the high selenium intake group in males. GPx activity, total cholesterol and triacylglycerols did not show any significant differences among the three different selenium intake groups. Dietary intake of non-fish Se had a positive correlation with HDL cholesterol, and an inverse correlation with the atherogenic index in all subjects and for females. On the other hand, dietary intake of fish-Se had no relationship with any serum lipids. Non-fish Se is an important factor in selenium status for the prevention of CHD.

The Effect of Red Pepper Waste Added to Compost on Selenium Content of Pleurotus citrinopileatus Singer

Directory of Open Access Journals (Sweden)

Fatih Kalyoncu

2016-03-01

Full Text Available In this study, selenium levels of P.citrinopileatus added different rates of red pepper waste to compost as a source of selenium were determined. For this purpose, six different compost groups were prepared and inoculated with P.citrinopileatus mycelia. Selenium levels of harvested mushrooms were analysed. In conclusion, 0.338 µg/g selenium were determined in one gram dry mushroom that red pepper waste added to compost at 5%. Mycelia growth and selenium accumulation were negatively affected by higher rates of red pepper waste.

Distribution of Iodine and Selenium in Selected Food Commodities

Directory of Open Access Journals (Sweden)

Strapáč I.

2016-03-01

Full Text Available The aim of this study was to investigate the distribution of the contents of iodine and selenium in selected food commodities. Fresh food commodities were mineralized and analysed for their iodine and selenium content by Inductively Coupled Plasma-Mass Spectrometry using the calibration curve as the method for determining the contents of the elements. The average fruit and vegetables concentrations of iodine were very low. The cow’s milk, other dairy products, eggs, poultry, fresh water fish, beef, liver, and mushrooms are frequently regarded as the most important natural source of dietary iodine from common foods. The higher concentrations of selenium were recorded in the kidney, liver, pork, beef, poultry, fresh water fish, hen’s eggs, cow’s milk, other dairy products, wheat flour, fats, coffee, peppers, mushrooms and potatoes.

Deposition of selenium coatings on beryllium foils. Revision 1

International Nuclear Information System (INIS)

Erikson, E.D.; Tassano, P.L.; Reiss, R.H.; Griggs, G.E.

1984-01-01

A technique for preparing selenium films on 50.8 micrometers thick beryllium foils is described. The selenium was deposited in vacuum from a resistance heated evaporation source. A water-cooled enclosure was used to minimize contamination of the vacuum system and to reduce the exposure of personnel to toxic and obnoxious materials. Profilometry measurements of the coatings indicated selenium thicknesses of 5.5, 12.9, 37.5, 49.8 and 74.5 micrometers. The control of deposition rate and of coating thickness was facilitated using a commercially available closed-loop programmable deposition controller. The x-ray transmission of the coated substrates was measured using a tritiated zirconium source. The transmissivities of the film/substrate combination are presented for the range of energies from 4 to 20 keV

Efficient pricing and investment in electricity markets with intermittent resources

International Nuclear Information System (INIS)

Chao, Hung-po

2011-01-01

Facing growing technological and environmental challenges, the electricity industry needs effective pricing mechanism to promote efficient risk management and investment decisions. In a restructured electricity market with competitive wholesale prices and traditionally regulated retail rates, however, there are technical and institutional barriers that prevent dynamic pricing with price responsive demand. In regions with limited energy storage capacity, intermittent renewable resources present special challenges. This could adversely affect the effectiveness of public policies causing inefficient investments in energy technologies. In this paper, we present an updated economic model of pricing and investment in restructured electricity market and use the model in a simulation study for an initial assessment of renewable energy strategy and alternative pricing mechanisms. A key objective of the study is to shed light on the policy issues so that effective decisions can be made to improve efficiency. - Highlights: → Renewable resources present special challenges in regions with limited energy storage capacity. → This paper presents an updated economic model of pricing and investment in restructured electricity market. → A simulation study assesses renewable energy strategy and alternative pricing mechanisms. → The study results inform policy decisions to improve efficient investments in energy technologies.

Transcriptome profiling reveals the immune response of goose T cells under selenium stimuli.

Science.gov (United States)

Cao, Nan; Li, Wanyan; Li, Bingxin; Tian, Yunbo; Xu, Danning

2017-12-01

The goose is an economically important poultry species and a principal natural host of avian viruses. This study aimed to determine the effects of selenium on the immune response of geese. Under selenium stimulation, gene expression profiling was investigated using transcriptome sequencing. The selenoproteins were promoted by selenium stimulation, while the heat shock proteins, interleukin and interferons were mainly down-regulated. After comparison, 2228 differentially expressed genes were primarily involved in immune and environmental response, and infectious disease and genetic information processing related pathways were identified. Specifically, the enzymes of the lysosomes which acted as a safeguard in preventing pathogens were mostly up-regulated and six randomly selected differentially expressed genes were validated by quantitative polymerase chain reaction. In addition, the most proportional increased transcription factor family basic helix-loop-helix (bHLH) located in the 5' flank of selenoprotein P-like protein for selenium metabolism was identified by response to the selenium stimulation in this study. These analyses show that selenium can promote immune function by activating selenoproteins, transcript factors and lysosome pathway related genes, while weakening cytokine content genes in geese. © 2017 Japanese Society of Animal Science.

The Evolving Role of Selenium in the Treatment of Graves' Disease and Ophthalmopathy

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Leonidas H. Duntas

2012-01-01

Full Text Available Graves' disease (GD and ophthalmopathy (GO are organ-specific autoimmune-inflammatory disorders characterized by a complex pathogenesis. The inflammatory process is dominated by an imbalance of the antioxidant-oxidant mechanism, increased production of radical oxygen species (ROS, and cytokines which sustain the autoimmune process and perpetuate the disease. Recently, selenium, which is a powerful antioxidant, has been successfully applied in patients with mild GO, slowing the progression of disease, decreasing the clinical activity score, and appreciably improving the quality of life. The mechanisms of selenium action are variable. The aim of this review is to summarize the actions of selenium in GD and GO. Selenium as selenocysteine is incorporated in selenoproteins, such as glutathione peroxidase which catalyzes the degradation of hydrogen peroxide and lipid hydroperoxide that are increasingly produced in hyperthyroidism. Moreover, selenium decreases the formation of proinflammatory cytokines, while it contributes, in synergy with antithyroid drugs, to stabilization of the autoimmune process in GD and alleviation of GO. It is now to be clarified whether enforced nutritional supplementation has the same results and whether prolonging selenium administration may have an impact on the prevention of disease.

Efficient Metropolitan Resource Allocation

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Richard Arnott

2016-05-01

Full Text Available Over the past 30 years Calgary has doubled in size, from a population of 640,645 in 1985 to 1,230,915 in 2015. During that time the City has had five different mayors, hosted the Winter Olympics, and expanded the C-Train from 25 platforms to 45. Calgary’s Metropolitan Area has grown too, with Airdrie, Chestermere, Okotoks and Cochrane growing into full-fledged cities, ripe with inter-urban commuters.* And with changes to provincial legislation in the mid-’90s, rural Rocky View County and the Municipal District of Foothills are now real competitors for residential, commercial and industrial development that in the past would have been considered urban. In this metropolitan system, where people live, their household structure, and their place of work informs the services they need to conduct their daily lives, and directly impacts the spatial character of the City and the broader region. In sum, Metropolitan Calgary is increasingly complex. Calgary and the broader metropolitan area will continue to grow, even with the current economic slowdown. Frictions within Calgary, between the various municipalities in the metropolitan area, and the priorities of other local authorities (such as the School Boards and Alberta Health Services will continue to impact the agendas of local politicians and their ability to answer to the needs of their residents. How resources – whether it is hard infrastructure, affordable housing, classrooms, or hospital beds – are allocated over space and how these resources are funded, directly impacts these relationships. This technical paper provides my perspective as an urban economist on the efficient allocation of resources within a metropolitan system in general, with reference to Calgary where appropriate, and serves as a companion to the previously released “Reflections on Calgary’s Spatial Structure: An Urban Economists Critique of Municipal Planning in Calgary.” It is hoped that the concepts reviewed

Production of urinary selenium metabolites in the rat following 75SeO32- administration

International Nuclear Information System (INIS)

Kiker, K.W.; Burk, R.F.

1974-01-01

Urinary metabolites of 75 Se were studied in male Holtzmann rats fed a Torula yeast diet with either no selenium (basal) or 0.5 ppM selenium (selenium) added as sodium selenite. The animals were anesthetized, a ureter was cannulated, and 20 μCi of 75 SeO 3 2- were injected intraportally. Only a small fraction (1.3 percent) of the injected 75 Se was excreted in 6 h by animals fed the basal diet but 13.3 percent was excreted by animals fed the selenium diet. Paper chromatography showed that both groups excreted mostly inorganic 75 Se in the first 10 min. A decrease in 75 Se excretion followed, and then, 70 min after the collection was started, the selenium diet group had an increase in 75 Se excretion which persisted for the rest of the 6 h and consisted mainly of the organic metabolites trimethylselenonium ion and U-2. 75 Se excretion remained low in the basal diet group. Liver uptake and release of 75 Se in the 1 h following intraperitoneal 75 SeO 3 2- injection was much greater in the selenium diet rats than in the basal diet rats. These results suggest that the greater excretion of 75 Se by rats fed the selenium diet than that by rats fed the basal diet was due to increased production of organic urinary selenium metabolites by the liver. (U.S.)

Analysis of resource use efficiency among soybean ( Glycine max ...

African Journals Online (AJOL)

Also, 87.5% of the farmers were in their active age, and 81.7% utilized their personal saving as a major source of finance for production. The result of the production function analysis indicated that 87.21% of the variation in the output of soybean is explained for by the independent variables. Resource-use efficiency ...

Selenium prevents tumor development in a rat model for chemical carcinogenesis

DEFF Research Database (Denmark)

Bjorkhem-Bergman, L.; Torndal, U. B.; Eken, S.

2005-01-01

Previous studies in animals and humans have shown that selenium compounds can prevent cancer development. In this work we studied the tumor preventive effect of selenium supplementation, administrated as selenite, in the initiation, promotion and progression phases in a synchronized rat model for...

Ameliorative effects of selenium and zinc

African Journals Online (AJOL)

Methidathion-induced hematological, biochemical and hepatohistological alterations in rat: Ameliorative effects of selenium and zinc. L Barkat, A Boumendjel, C Abdennour, MS Boulakoud, A El Feki, M Messarah ...

Low selenium status affects arsenic metabolites in an arsenic exposed population with skin lesions.

Science.gov (United States)

Huang, Zhi; Pei, Qiuling; Sun, Guifan; Zhang, Sichum; Liang, Jiang; Gao, Yi; Zhang, Xinrong

2008-01-01

The antagonistic effects between selenium (Se) and arsenic (As) suggest that low selenium status plays important roles in arsenism development. However, no study has been reported for humans suffering from chronic arsenic exposure with low selenium status. Sixty-three subjects were divided into 2 experimental groups by skin lesions (including hyperkeratosis, depigmentation, and hyperpigmentation). Total urine and serum concentrations of arsenic and selenium were determined by ICP-MS with collision/reaction cell. Arsenic species were analysed by ICP-MS coupled with HPLC. The mean concentration of As in the drinking waters was 41.5 microg/l. The selenium dietary intake for the studied population was 31.7 microg Se/d, and which for the cases and controls were 25.9 and 36.3 microg Se/d, respectively. Compared with the controls, the skin lesions cases had lower selenium concentrations in serum and urine (41.4 vs 49.6 microg/l and 71.0 vs 78.8 microg/l, respectively), higher inorganic arsenic (iAs) in serum (5.2 vs 3.4 microg/l, PiAs in serum and urine (20.2) vs 16.9% and 18.3 vs 14.5%, respectively, PiAs and its inhibition to be biotransformed to DMA occurred in human due to chronic exposure of low selenium status.