WorldWideScience

Sample records for synthetic studies leading

  1. In vitro and in vivo studies of lead immobilization by synthetic hydroxyapatite

    International Nuclear Information System (INIS)

    Arnich, Nathalie; Lanhers, Marie-Claire; Laurensot, Franck; Podor, Renaud; Montiel, Antoine; Burnel, Daniel

    2003-01-01

    Lead immobilization by solid hydroxyapatite significantly reduces lead concentration and bioavailability in water. - Apatite appears a useful compound for removing lead from water, due to its ability to immobilize the metal by precipitation. In dilute solution, dissolved hydroxyapatite [HA, Ca 10 (PO 4 ) 6 (OH) 2 ] provided phosphates that were reactive with aqueous lead (molar ratio HA/Pb=1/10) forming precipitates at around pH 6. These dissolved at a more acidic pH (3). Solid HA in contact with Pb 2+ ions, led to the formation of pyromorphite [Pb 10 (PO 4 ) 6 (OH) 2 ], identified by X-ray diffraction and insoluble at pH tested (3-8). The amount of pyromorphite increased with the weight ratio of HA/Pb. When this one increased from 1 to 1000, lead precipitated as pyromorphite rose from 19 to 99%. In vivo experiments on rats confirmed the in vitro results. In fact, lead bioavailability assessed by intestinal perfusion was unchanged in the presence of dissolved HA, whereas it was significantly lower in the presence of solid HA, evaluated by gastric intubation, at a weight ratio equal to 10 (amount of lead absorbed decreased by 60%). Apatite could be an effective means of immobilizing lead in drinking or sewage, since accidental pyromorphite ingestion does not yield bioavailable lead

  2. Synthetic α-Conotoxin Mutants as Probes for Studying Nicotinic Acetylcholine Receptors and in the Development of Novel Drug Leads

    Directory of Open Access Journals (Sweden)

    Christopher J. Armishaw

    2010-06-01

    Full Text Available α-Conotoxins are peptide neurotoxins isolated from venomous marine cone snails that are potent and selective antagonists for different subtypes of nicotinic acetylcholine receptors (nAChRs. As such, they are valuable probes for dissecting the role that nAChRs play in nervous system function. In recent years, extensive insight into the binding mechanisms of α-conotoxins with nAChRs at the molecular level has aided in the design of synthetic analogs with improved pharmacological properties. This review examines the structure-activity relationship studies involving α-conotoxins as research tools for studying nAChRs in the central and peripheral nervous systems and their use towards the development of novel therapeutics.

  3. News: Synthetic biology leading to specialty chemicals

    Science.gov (United States)

    Synthetic biology can combine the disciplines of biology, engineering, and chemistry productively to form molecules of great scientific and commercial value. Recent advances in the new field are explored for their connection to new tools that have been used to elucidate productio...

  4. News: Synthetic biology leading to specialty chemicals ...

    Science.gov (United States)

    Synthetic biology can combine the disciplines of biology, engineering, and chemistry productively to form molecules of great scientific and commercial value. Recent advances in the new field are explored for their connection to new tools that have been used to elucidate production pathways to a wide variety of chemicals generated by microorganisms. The selection and enhancement of microbiological strains through the practice of strain engineering enables targets of design, construction, and optimization. This news column aspires to cover recent literature relating to the development and understanding of clean technology.

  5. Treating Lead Toxicity: Possibilities beyond Synthetic Chelation

    Directory of Open Access Journals (Sweden)

    Shambhavi Tannir

    2013-01-01

    Full Text Available Lead, a ubiquitous metal, is one of the most abundant elements present on earth. Its easy availability and cost effectiveness made it an extremely popular component in the industrial revolution. However, its hazardous health effects were not considered at the time. Over the last few decades, with the adverse effects of lead coming to the forefront, nations across the world have started to recognize and treat lead toxicity. The most reliable and used method until now has been chelation therapy. Recent research has suggested the use of natural products and sources to treat lead poisoning with minimal or no side effects. This review has tried to summarize a few of the natural products/sources being investigated by various groups.

  6. Removal of Lead from Synthetic Solutions by Protonated Teleosts Biomass

    Directory of Open Access Journals (Sweden)

    Muhammad Aqeel Ashraf

    2012-01-01

    Full Text Available Lead is considered as a general protoplasmic poison which is cumulative and slow acting. It is used in different industrial processes. Its contamination in water may cause serious environmental problems. So removal of lead from environment is very necessary. For its removal the most suitable and cheapest process is biosorption. It is a process of passive metal binding by biomass. The biosorbent used in this study is teleosts biomass (fish scales collected from local market. The purpose of this study is to search the effect of acid treatment on biosorbent and to optimize conditions for the uptake capacity of biosorbent. The optimal conditions for the Pb2+ biosorption capacity of teleosts biomass (fish scales as waste of white meat was investigated. For this purposes, the biomass was subjected to chemical treatments with mono, di and tri-protic acids such as hydrochloric acid, sulphuric acid and phosphoric acid. Among the treatment methods used, the highest Pb2+ uptake was obtained with hydrochloric acid treatment of biomass. The effect of pH, biomass granular size, biomass concentration and initial Pb2+ ion concentration was studied. The highest Pb2+ removal (65.39% was obtained at pH 4.0 for 50 mg L−1 initial lead ion concentration with biomass granular size 80 micron and concentration of 0.05 g. The uptake was 75.70 mg g−1. The equilibrium data were analyzed using the Langmuir and Freundlich adsorption isotherm. The characteristic parameters for each isotherm were determined. Both the isotherms provided the best correlation for Pb2+ on to the biomass. These results showed that teleosts biomass (fish scales is a potential biomass to remove Pb2+ ions from synthetic solutions so also with lead contaminated water. These values can be compared with those observed for other biosorbents and it is considerably higher than the value obtained with the majority of the biosorbent.

  7. IN SITU LEAD STABILIZATION USING NATURAL AND SYNTHETIC APATITE

    Directory of Open Access Journals (Sweden)

    T. Kaluđerović Radoičić

    2008-11-01

    Full Text Available In this work, mineral apatite was investigated for the remediation of lead contamination. Two different apatite minerals were used: synthetic apatite, Ca10(PO46(OH2 (hereafter denoted as HAP and natural apatite from Lisina, near Bosilegrad, Serbia (hereafter denoted as LA. Phosphate ore from Lisina deposit consists of 43.3 % apatite in the form of fluorapatite, Ca10(PO46(F2. Sorption properties of HAP and LA were investigated. The results show that both of these minerals are effective in lead removal from the water solution. Sorption capacity of HAP obtained in this experiment is 0.216 mmol Pb/g HAP, while the value for LA is 0.162 mmol Pb/g LA. Modeling of these systems was conducted using Visual Minteq computer program. The values obtained from the computer simulation were compared to experimental values.

  8. Optimization of Lead Removal via Napier Grass in Synthetic Brackish Water using Response Surface Model

    Science.gov (United States)

    Hongsawat, P.; Suttiarporn, P.; Wutsanthia, K.; Kongsiri, G.

    2018-03-01

    The efficiency of the lead (Pb) phytoremediation by Napier grass was studied on the plant’s growth and plant’s tolerance on the Pb toxicity in synthetic brackish water. It was found that the plant was high tolerance to high level of Pb concentration (10 mg/l) in synthetic brackish water. Which revealed on the possibilities of plant’s growth under the presence of Pb contaminated condition. According to the Pb removal efficiency, the highest one (88.63±4.9%) was found at 10 ppm Pb concentration, 0.3 g/l NaCl concentration during the period 45 day. However, this study investigated the optimum condition for lead (Pb) removal from synthetic brackish water using phytoremediation treatment with Napier grass through a Box-Behnken Design. Three operational variables, i.e. Pb concentration (1, 5.5, 10 mg/l), NaCl (0.1, 0.3, 0.5 g/l) and period time (7, 26, 45 day), were determined. The results were provided evidence that the highest Pb removal efficiency (93.56%) from synthetic brackish water via Napier grass was Pb and NaCl concentration at 10 mg/l and 0.5 g/l during 45 day.

  9. Lead (Pb2+ Removal from Synthetic Aqueous Solution Using Food Waste Ash

    Directory of Open Access Journals (Sweden)

    M Afsharnia

    2016-11-01

    Full Text Available Lead (Pb2+ Removal from Synthetic Aqueous Solution Using Food Waste Ash AfsharniaM (Ph.D1, Shams M (M.Sc2, Sajjadi SA (Ph.D1, Qasemi  M (M.Sc3 1. Assistant Professor, Department of Environmental Health Engineering, ,Gonabad University of Medical Sciences, Gonabad, Iran. 2. Instructor, Department of Environmental Health Engineering, Gonabad University of Medical Sciences, Gonabad, Iran. 3. Corresponding Author: M.Sc Student in Environmental Health Engineering, Gonabad University of Medical Sciences, Gonabad, Iran Abstract Introduction: Lead is a toxic heavy metal in some industrial wastewater that can pose hazards to the environment and human health. Adsorption is a promising technology for decontamination of water. The present study evaluated the efficiency of food waste ash as a cheap, environmental compatible and available adsorbent, in lead removal from synthetic aqueous solution. Methods: In the presentexperimental study, lead removal by  using food waste ash in series of batch experiments were investigated. The influence of different parameters on adsorption such as adsorbent dose, contact time, pH, lead concentrationand adsorption temperature also studied. The experimental data finally were analyzed using excel and the adsorption behavior was fitted  to isotherm and kinetic models. Results: The study showed that lead removal decreased with increasing lead concentration. In addition, it was found that lead adsorption increased by increasing pH and temperature. comparing adsorption capacity of food waste ash with the adsorbents used by scientist also showed the former have a remarkable higher capacity toward lead adsorption. The adsorption process also showed a good conformity to Freundlich model. Conclusion: Current study endorsed the use of food waste ash in real adsorption systems, as a cheap and available adsorbent with high capacity toward lead.

  10. Evaluation of dum palm kernel activated carbon in chromium and lead adsorption from synthetic waste water

    Directory of Open Access Journals (Sweden)

    HI Mohammed

    2016-09-01

    Full Text Available This study aimed at the co-current removal of chromium and lead ions from synthetic waste water using dum palm kernel activated carbon. The adsorption experiment was conducted by varying time, pH and concentrations of the simulated solution. The data obtained were analyzed, and the best conditions for the uptake were at pH of 6, equilibrium time of 40 minutes. The two best isotherms models for the adsorption system were Sip, and Dubinin–Radushkevich, models respectively. Based on the Temkin adsorption energy calculated as 9.5793 and 0.4997 J/mol, the uptake of lead and chromium were chemisorption and physico-sorption, respectively. The maximum uptake calculated from Dubinin–Radushkevich plots were 14.1696 and 7.7191 mg/g, for lead and chromium, respectively.International Journal of Environment Vol.5(3 2016, pp.104-118

  11. Evaluation of natural clay Brasgel as adsorbent in removal of lead in synthetic waste water

    International Nuclear Information System (INIS)

    Lima, W.S.; Rodrigues, M.G.F.; Mota, M.F.; Patricio, A.C.L.; Silva, M.M.

    2012-01-01

    The smectite clays have high adsorption capacity and cation exchange. Due to its chemical and physical characteristics, they can be effectively used as adsorbent of pollutants (such as metal ions). The initial objective of this study was to characterize the clay Brasgel through the techniques of X-Ray Diffraction (XRD), X-Ray Spectrometry by Energy Dispersive (EDX) and nitrogen adsorption (BET method), seeking its use in removing lead (Pb 2+ ) from synthetic effluents. System was used in finite bath to assess the potential removal of lead (Pb 2+ ), following a 2 2 factorial experimental design with three center point experiments, taking as input variables: pH and initial concentrations of lead (Pb 2+ ). The clay has Brasgel clay in its composition that characterize it as a smectite clay. By having a large surface area, this clay showed great potential on the adsorption of metal ions. (author)

  12. A comparative study of the defluoridation efficiency of synthetic ...

    African Journals Online (AJOL)

    A comparative study of the defluoridation efficiency of synthetic dicalcium phosphate dihydrate (DCPD) and lacunar hydroxyapatite (L-HAp): An application of synthetic solution and Koundoumawa field water.

  13. Mammalian synthetic biology for studying the cell.

    Science.gov (United States)

    Mathur, Melina; Xiang, Joy S; Smolke, Christina D

    2017-01-02

    Synthetic biology is advancing the design of genetic devices that enable the study of cellular and molecular biology in mammalian cells. These genetic devices use diverse regulatory mechanisms to both examine cellular processes and achieve precise and dynamic control of cellular phenotype. Synthetic biology tools provide novel functionality to complement the examination of natural cell systems, including engineered molecules with specific activities and model systems that mimic complex regulatory processes. Continued development of quantitative standards and computational tools will expand capacities to probe cellular mechanisms with genetic devices to achieve a more comprehensive understanding of the cell. In this study, we review synthetic biology tools that are being applied to effectively investigate diverse cellular processes, regulatory networks, and multicellular interactions. We also discuss current challenges and future developments in the field that may transform the types of investigation possible in cell biology. © 2017 Mathur et al.

  14. Removal of Lead from Wastewater Contaminated with Chemical Synthetic Dye by Aspergillus terreus

    Directory of Open Access Journals (Sweden)

    Lamyai Neeratanaphan

    2015-07-01

    Full Text Available Novel isolated microorganisms have been demonstrated to efficiently remove lead from wastewater contaminated with chemical synthetic dye. In this study, the physical and chemical parameters of wastewater samples (including Pb concentrations were analyzed before and after treatment with microorganisms. The highest Pb concentration detected in wastewater was 0.788 mg/l. Investigations of the Pb tolerance and removal capacities of microorganism strains isolated from the wastewater sediment resulted in the selection of three fungal isolates (F102, F203 and F302. Interestingly, isolate F203 had a Pb tolerance of up to 100 mg/l. Using DNA barcoding and morphological characteristics, fungal isolate F203 was identified as Aspergillus terreus. Wastewater characteristics before treatment included a grayish black color with pH, TDS, BOD, COD and Pb concentrations higher than the Thailand standard values. Wastewater qualities after treatment with A. terreus showed definite improvement; however, the values of certain parameters were still higher than the allowed values based on the Thailand standard. The only improvement that fell within the allowed standard was the Pb concentration. Next, A. terreus was used for Pb adsorption in wastewater with an initial Pb concentration of 0.788 mg/l at time points corresponding to 0, 24, 48, 72, 96, 120, 144 and 168 h of incubation. The results showed that A. terreus could adsorb and remove higher amounts of Pb from wastewater than the other fungal isolates. Time course adsorption analysis showed the remaining Pb concentrations as 0.788, 0.213, 0.162, 0.117, 0.100, 0.066, 0.042 and 0.032 mg/l, respectively; the percentage of Pb removal could be estimated as 0, 72.97, 79.44, 85.15, 87.31, 91.62, 94.67 and 95.94%, respectively. In conclusion, A. terreus possessed the ability to adsorb up to 96% of Pb from chemical synthetic dye within 168 h. Thus, A. terreus might be suitable for adaptation and use in Pb treatment.

  15. Development and Application of a Synthetically-Derived Lead Biosensor Construct for Use in Gram-Negative Bacteria

    Directory of Open Access Journals (Sweden)

    Lara Bereza-Malcolm

    2016-12-01

    Full Text Available The use of lead in manufacturing has decreased significantly over the last few decades. However, previous widespread use of lead-containing products and their incorrect disposal has resulted in environmental contamination. Accumulation of harmful quantities of lead pose a threat to all living organisms, through inhalation, ingestion, or direct contact, resulting in lead poisoning. This study utilized synthetic biology principles to develop plasmid-based whole-cell bacterial biosensors for detection of lead. The genetic element of the lead biosensor construct consists of pbrR, which encodes the regulatory protein, together with its divergent promoter region and a promoterless gfp. GFP expression is controlled by PbrR in response to the presence of lead. The lead biosensor genetic element was cloned onto a low-copy number broad host range plasmid, which can stably exist in a range of laboratory and environmental isolates, including Pseudomonas, Shewanella, and Enterobacter. The biosensors constructed were found to be sensitive, rapid, and specific and could, as such, serve as monitoring tools for lead-contaminated water.

  16. Synthetic Medicinal Chemistry in Chagas' Disease: Compounds at The Final Stage of "Hit-To-Lead" Phase.

    Science.gov (United States)

    Cerecetto, Hugo; González, Mercedes

    2010-03-25

    Chagas' disease, or American trypanosomosiasis, has been the most relevant illness produced by protozoa in Latin America. Synthetic medicinal chemistry efforts have provided an extensive number of chemodiverse hits at the "active-to-hit" stage. However, only a more limited number of these have been studied in vivo in models of Chagas' disease. Herein, we survey some of the cantidates able to surpass the "hit-to-lead" stage discussing their limitations or merit to enter in clinical trials in the short term.

  17. Dissolution studies of synthetic soddyite and uranophane

    International Nuclear Information System (INIS)

    Casas, I.; Perez, I.; Torrero, E.; Bruno, J.; Cera, E.; Duro, L.

    1997-09-01

    The dissolution of synthetically obtained soddyite and uranophane has been studied in solutions of low ionic strength. These are the likely final phases of the oxidative alternation pathway of uranium dioxide. The thermodynamic and kinetic dissolution properties of these phases have been determined at different bicarbonate concentrations. The solubilities determined in the experiments with soddyite correspond fairly well to the theoretical model calculated with a log K 0 s0 =3.9±0.7. For uranophane, the best fitting was obtained for a log K 0 s0 =11.7±0.6. The dissolution rate in the presence of bicarbonate gave for soddyite an average value of 6.8(±4.4) 10 -10 mol m -2 s -1 . For uranophane, under the same experimental conditions, the following dissolution rate equation has been derived: r 0 (mol m -2 s -1 )=10 -9±2. [HCO 3 - ] 0.69±0.09 2

  18. Synthetic

    Directory of Open Access Journals (Sweden)

    Anna Maria Manferdini

    2010-06-01

    Full Text Available Traditionally materials have been associated with a series of physical properties that can be used as inputs to production and manufacturing. Recently we witnessed an interest in materials considered not only as ‘true matter’, but also as new breeds where geometry, texture, tooling and finish are able to provoke new sensations when they are applied to a substance. These artificial materials can be described as synthetic because they are the outcome of various qualities that are not necessarily true to the original matter, but they are the combination of two or more parts, whether by design or by natural processes. The aim of this paper is to investigate the potential of architectural surfaces to produce effects through the invention of new breeds of artificial matter, using micro-scale details derived from Nature as an inspiration.

  19. Synthetic studies on heterocyclic natural products.

    Science.gov (United States)

    Ciufolini, Marco A

    2005-08-01

    This article reviews past and ongoing research in the author's laboratory directed toward the synthesis of natural products displaying an azaspirocyclic framework, or incorporating a medium-ring nitrogen heterocycle. New synthetic technologies were devised in order to address the synthetic problems posed by the target molecules. Thus, efforts in the area of azaspirocyclic substances have relied on an oxidative amidation of phenols promoted by iodobenzene diacetate, whereas access to medium-ring nitrogen heterocycles has been secured by means of a ring expansion sequence that relies on the fragmentation of an aziridine triggered by a homo-Brook transposition. Details of the development of these technologies are presented, together with applications to the total synthesis of FR-901483, TAN-1251C, cylindricines, and mitomycinoids.

  20. Visualization study of hybrid synthetic jets

    Czech Academy of Sciences Publication Activity Database

    Broučková, Zuzana; Trávníček, Zdeněk

    2015-01-01

    Roč. 18, č. 4 (2015), s. 581-593 ISSN 1343-8875 R&D Projects: GA ČR GA14-08888S Institutional support: RVO:61388998 Keywords : synthetic jet * efficiency * flow visualization Subject RIV: JU - Aeronautics, Aerodynamics, Aircrafts Impact factor: 0.720, year: 2015 http://link.springer.com/article/10.1007/s12650-014-0256-8

  1. Synthetic strategies for studying embryonic development.

    Science.gov (United States)

    Ouyang, Xiaohu; Chen, James K

    2010-06-25

    Developmental biology has evolved from a descriptive science to one based on genetic principles and molecular mechanisms. Although molecular biology and genetic technologies have been the primary drivers of this transformation, synthetic strategies have been increasingly utilized to interrogate the mechanisms of embryonic patterning with spatial and temporal precision. In this review, we survey how chemical tools and engineered proteins have been used to perturb developmental processes at the DNA, RNA, protein, and cellular levels. We discuss the design principles, experimental capabilities, and limitations of each method, as well as future challenges for the chemical and developmental biology communities.

  2. A comparative study of the defluoridation efficiency of synthetic ...

    African Journals Online (AJOL)

    user

    synthetic solution of sodium fluoride (NaF) and natural waters of Koudoumawa are studied. The fluoride removal capacity is as follows: ... to avoid health effects of fluoride water poisoning (WHO,. 1996). In over a total of 211 studied ... bicarbonate concentration of about 167.7 to 216.08 mg/l. A study carried out by UNICEF in ...

  3. Comparative study of the electronic structure of natural and synthetic ...

    Indian Academy of Sciences (India)

    ... have studied the Cr–K-edge XANES and EXAFS in natural Indian rubies from two sources and a synthetic ruby at ESRF. Weight % of various constituents in them is determined using EDAX measurements. Taking the results from the three techniques together we are able to demonstrate their feasibility in quantitative study ...

  4. A Preliminary Trypanocidal Study of Natural and Synthetic ...

    African Journals Online (AJOL)

    Eighty healthy Wistar albino rats were used to investigate the trypanocidal effect of natural and synthetic supplements of zinc and magnesium in combination with diminazene aceturate in Trypanosoma congolense-inoculated rats. The rats were randomly divided into eight groups in study '1' (involving the natural ...

  5. Comparative study of the electronic structure of natural and synthetic ...

    Indian Academy of Sciences (India)

    Comparative study of the electronic structure of natural and synthetic rubies using XAFS and EDAX analyses ... Electronics and Engineering Research Institute, Pilani 333 031, India; Dipartimento di Fisica, Universita di Roma, “La Sapienza”, 00185 P,le A.Moro, Roma, Italy; Gem Testing Laboratory, Jaipur 302 003, India ...

  6. Comparative study of the electronic structure of natural and synthetic ...

    Indian Academy of Sciences (India)

    Unknown

    , Roma, Italy. MS received 2 May 2002. Abstract. We have studied the Cr–K-edge XANES and EXAFS in natural Indian rubies from two sources and a synthetic ruby at ESRF. Weight % of various constituents in them is determined using EDAX ...

  7. Norbadione A: synthetic approach and cesium complexation studies

    International Nuclear Information System (INIS)

    Desage - El Murr, M.

    2003-10-01

    This work was dedicated to the study of the synthesis and complexation studies of norbadione A: a pigment originating from a mushroom. A synthetic approach, based on a double Suzuki-Miyaura coupling, was developed. This strategy was applied with high yields to the synthesis of various norbadione A analogues, as well as to the synthesis of simple pulvinic acids. Access to functionalized precursors of the molecule was also studied and the final coupling remains to be done. Besides, a speciation study based on electro-spray ionization mass spectrometry was conducted with norbadione A and one of the analogues. This study allowed the assessment of the cesium complexation abilities of each molecule. Structural data was also obtained and complexation constants were calculated. Finally, norbadione A and various synthetic products have been tested via high-throughput screening methods and strong antioxidant properties were observed. Other biological results are also reported. (author)

  8. Exploratory comparative study on the diffusion of synthetic cannabinoids and synthetic cathinones.

    Science.gov (United States)

    Arfken, Cynthia L; Owens, Darlene; Madeja, Cheryl; DeAngelis, Christina

    2014-01-01

    The use of synthetic cannabinoids and cathinones in southeastern Michigan was explored using Roger's Diffusion of Innovation theory. A mixed methods approach after specific synthetic cannabinoids and cathinone compounds were scheduled was used that included analysis of treatment admissions for two years, surveys of 15 substance abuse treatment providers, and qualitative interviews with a purposive sample of 24 participants. The participant system norm supported trying new drugs, and both drugs were confirmed to have been easier to access than traditional drugs. The participants had negative views of synthetic cathinones due to one sensational news story without counterbalancing positive experiences in their social environment. Although synthetic cannabinoids were also linked to a sensational news story, it was counterbalanced by positive personal experiences. These differences contributed to greater use of synthetic cannabinoids compared to synthetic cathinones as evidenced by admissions, providers' reports, and participants' reports. All participants expressed a preference for traditional drugs, indicating that novel drugs had no relative advantage over other drugs of abuse. Diffusion of Innovation theory can provide a framework for understanding the differential use of novel drugs.

  9. First studies of lead pollution in Guanabara

    International Nuclear Information System (INIS)

    Silveira Branquinho, C.L. da.

    1973-01-01

    The main sources of direct lead intake are studied, and metal concentrations in several medium are examined. Lead was extracted by dithizone in C Cl 4 , being determined by optical spectrophotometry. 2 1 2 Pb was used as a radioactive tracer in low concentration measurements of the metal, and analysis of its 239 KeV peak was done by a Ge-Li detector. In blood samples, the metal was complexed and extracted with APDC in MIBK, being measured by flame less atomic absorption spectrophotometry. Air samples were also collected for periods of 24 hours and 90 minutes. Representative street dust samples were examined, showing a strict correlation with lead in air. It was also estimated the amount of lead in some human blood samples. (author)

  10. Structural and Functional Studies of Experimental HIV Synthetic Peptide Immunogens

    Science.gov (United States)

    1997-10-01

    Work performed in this grant continues to address 2 major problems in HIV synthetic peptide vaccine development: (1) the ability of synthetic...In technical aim #1, intranasal immunization with HIV synthetic peptide immunogens was found to be effective for the induction of serum anti-peptide

  11. Synthetic studies toward to the first totalsynthesis of Floribundane B

    Directory of Open Access Journals (Sweden)

    João V. S. Silva

    2012-06-01

    Full Text Available Floribundane B is an iridoid recently isolated by D. I. M. de  Mendonça and coworkers from the leaves and the bark of the trunk of Hymenodictyon floribundum B. L. Rob, a plant used in Angola folk medicine to treat fever. Our retrosynthetic analysis to Floribundane B has the Hydroxylactone 1 as key intermediate, which was obtained in  moderated overall yield from the Baylis-Hillman adduct 2. Synthetic studies are on going to afford the first total synthesis of Floribundane B and to confirm the planar structure proposed by D. I. M. de Mendonça and coworkers.

  12. Synthetic strategies for plant signalling studies: molecular toolbox and orthogonal platforms.

    Science.gov (United States)

    Braguy, Justine; Zurbriggen, Matias D

    2016-07-01

    Plants deploy a wide array of signalling networks integrating environmental cues with growth, defence and developmental responses. The high level of complexity, redundancy and connection between several pathways hampers a comprehensive understanding of involved functional and regulatory mechanisms. The implementation of synthetic biology approaches is revolutionizing experimental biology in prokaryotes, yeasts and animal systems and can likewise contribute to a new era in plant biology. This review gives an overview on synthetic biology approaches for the development and implementation of synthetic molecular tools and techniques to interrogate, understand and control signalling events in plants, ranging from strategies for the targeted manipulation of plant genomes up to the spatiotemporally resolved control of gene expression using optogenetic approaches. We also describe strategies based on the partial reconstruction of signalling pathways in orthogonal platforms, like yeast, animal and in vitro systems. This allows a targeted analysis of individual signalling hubs devoid of interconnectivity with endogenous interacting components. Implementation of the interdisciplinary synthetic biology tools and strategies is not exempt of challenges and hardships but simultaneously most rewarding in terms of the advances in basic and applied research. As witnessed in other areas, these original theoretical-experimental avenues will lead to a breakthrough in the ability to study and comprehend plant signalling networks. © 2016 The Authors The Plant Journal © 2016 John Wiley & Sons Ltd.

  13. Synthetic strategies for plant signalling studies: molecular toolbox and orthogonal platforms

    KAUST Repository

    Braguy, Justine

    2016-05-26

    Plants deploy a wide array of signalling networks integrating environmental cues with growth, defence and developmental responses. The high level of complexity, redundancy and connection between several pathways hampers a comprehensive understanding of involved functional and regulatory mechanisms. The implementation of synthetic biology approaches is revolutionizing experimental biology in prokaryotes, yeasts and animal systems and can likewise contribute to a new era in plant biology. This review gives an overview on synthetic biology approaches for the development and implementation of synthetic molecular tools and techniques to interrogate, understand and control signalling events in plants, ranging from strategies for the targeted manipulation of plant genomes up to the spatiotemporally resolved control of gene expression using optogenetic approaches. We also describe strategies based on the partial reconstruction of signalling pathways in orthogonal platforms, like yeast, animal and in vitro systems. This allows a targeted analysis of individual signalling hubs devoid of inter-connectivity with endogenous interacting components. Implementation of the interdisciplinary synthetic biology tools and strategies is not exempt of challenges and hardships but simultaneously most rewarding in terms of the advances in basic and applied research. As witnessed in other areas, these original theoretical-experimental avenues will lead to a breakthrough in the ability to study and comprehend plant signalling networks. This article is protected by copyright. All rights reserved.

  14. Autonomy and Fear of Synthetic Biology: How Can Patients' Autonomy Be Enhanced in the Field of Synthetic Biology? A Qualitative Study with Stable Patients.

    OpenAIRE

    Rakic Milenko; Wienand Isabelle; Shaw David; Nast Rebecca; Elger Bernice S

    2017-01-01

    We analyzed stable patients' views regarding synthetic biology in general the medical application of synthetic biology and their potential participation in trials of synthetic biology in particular. The aim of the study was to find out whether patients' views and preferences change after receiving more detailed information about synthetic biology and its clinical applications. The qualitative study was carried out with a purposive sample of 36 stable patients who suffered from diabetes or gou...

  15. Random chromosome elimination in synthetic Triticum-Aegilops amphiploids leads to development of a stable partial amphiploid with high grain micro- and macronutrient content and powdery mildew resistance.

    Science.gov (United States)

    Tiwari, Vijay K; Rawat, Nidhi; Neelam, Kumari; Kumar, Sundip; Randhawa, Gursharn S; Dhaliwal, Harcharan S

    2010-12-01

    Synthetic amphiploids are the immortal sources for studies on crop evolution, genome dissection, and introgression of useful variability from related species. Cytological analysis of synthetic decaploid wheat (Triticum aestivum L.) - Aegilops kotschyi Boiss. amphiploids (AABBDDUkUkSkSk) showed some univalents from the C1 generation onward followed by chromosome elimination. Most of the univalents came to metaphase I plate after the reductional division of paired chromosomes and underwent equational division leading to their elimination through laggards and micronuclei. Substantial variation in the chromosome number of pollen mother cells from different tillers, spikelets, and anthers of some plants also indicated somatic chromosome elimination. Genomic in situ hybridization, fluorescence in situ hybridization, and simple sequence repeat markers analysis of two amphiploids with reduced chromosomes indicated random chromosome elimination of various genomes with higher sensitivity of D followed by the Sk and Uk genomes to elimination, whereas 1D chromosome was preferentially eliminated in both the amphiploids investigated. One of the partial amphiploids, C4 T. aestivum 'Chinese Spring' - Ae. kotschyi 396 (2n = 58), with 34 T. aestivum, 14 Uk, and 10 Sk had stable meiosis and high fertility. The partial amphiploids with white glumes, bold seeds, and tough rachis with high grain macro- and micronutrients and resistance to powdery mildew could be used for T. aestivum biofortification and transfer of powdery mildew resistance.

  16. Microstructural study of synthetic spinel from natural raw materials

    Energy Technology Data Exchange (ETDEWEB)

    Chao, Y.; Hagni, R.D. (Univ. of Missouri, Rolla, MO (United States). Dept. of Geology and Geophysics); Caballero, A. (Inst. de Ceramica y Vidrio, Madrid (Spain)); Moore, R.E. (Univ. of Missouri, Rolla, MO (United States). Dept. of Ceramic Engineering)

    1993-03-01

    Alumina-magnesia spinel is being used increasingly as a high quality refractory in furnace and cement rotary kiln applications, but the costs of synthetic powders and grains limit its application. Different sources of bauxite from Guyana and China and diaspore from Missouri have been utilized to synthesize spinel for refractories in order to reduce the cost. The purpose of this research is to examine extent and character or spinel formation under different firing conditions and varying Al[sub 2]O[sub 3]:MgO ratios. Finely ground raw materials were mixed with hardburned magnesia in certain ratios to form spinel. X-ray analysis has been completed and shows that spinel readily occurs, after heating at 1,550 C, together with some impurity minerals such as mullite, rutile, corundum and some glassy phases. In order to study the microstructure, quantitative analysis, reflected light microscopy, scanning electron microscopy (SEM) and automatic image analysis are currently being utilized to determine the amount and distribution of each phase present in 39 samples prepared at different firing temperatures and with different chemical compositions. The results of this investigation provide a better understanding of the character of the microstructures of synthetic spinels.

  17. Leading with integrity: a qualitative research study.

    Science.gov (United States)

    Storr, Loma

    2004-01-01

    This research paper gives an account of a study into the relationship between leadership and integrity. There is a critical analysis of the current literature for effective, successful and ethical leadership particularly, integrity. The purpose and aim of this paper is to build on the current notions of leadership within the literature, debate contemporary approaches, focussing specifically on practices within the UK National Health Service in the early 21st century. This leads to a discussion of the literature on ethical leadership theory, which includes public service values, ethical relationships and leading with integrity. A small study was undertaken consisting of 18 interviews with leaders and managers within a District General HospitaL Using the Repertory Grid technique and analysis 15 themes emerged from the constructs elicited, which were compared to the literature for leadership and integrity and other studies. As well as finding areas of overlap, a number of additional constructs were elicited which suggested that effective leadership correlates with integrity and the presence of integrity will improve organisational effectiveness. The study identified that perceptions of leadership character and behaviour are used to judge the effectiveness and integrity of a leader. However, the ethical implications and consequences of leaders' scope of power and influence such as policy and strategy are somewhat neglected and lacking in debate. The findings suggest that leaders are not judged according to the ethical nature of decision making, and leading and managing complex change but that the importance of integrity and ethical leadership correlated with higher levels of hierarchical status and that it is assumed by virtue of status and success that leaders lead with integrity. Finally, the findings of this study seem to suggest that nurse leadership capability is developing as a consequence of recent national investment.

  18. Study of chemical and physical properties of synthetic carbonaceous materials

    Energy Technology Data Exchange (ETDEWEB)

    Kaloc, M.; Lesko, J.; Martineg, P.; Rojak, A.; Roubicek, V.; Weiss, Z.

    1980-01-01

    Results are presented of studying the chemical and physical properties of 17 samples of synthetic carbonaceous materials (''carbons'') of different origin and with different degree of thermal treatment, and for comparison two samples of natural graphite were tested. For all the samples an analysis was made of the element composition and they were studied by the methods DTA, TGA, IR-spectrometry, x-ray analysis and electron screen microscopy. The studies indicated that proper combination of these methods can provide a high quality evaluation of the initial materials and the processes of their processing, and also the attained carbonaceous materials from the viewpoint of using them in the modern sectors of technology: electrical metallurgy, electrical chemistry and electrothermal production, nuclear technology, production of semiconductor materials, etc.

  19. Synthetic Studies of Curved Heptagon-embedded Polycyclic Arenes

    Science.gov (United States)

    Cheung, Kwan Yin

    Polycyclic aromatic hydrocarbons (PAHs) are a class of compounds which is an area of intense research for its application in organic electronics. PAHs are usually flat molecules. However, when non-hexagonal rings are embedded into PAHs, curvature may be introduced to the PAHs backbone. In this thesis, synthetic studies of curved PAHs embedded with seven-membered rings are presented, in which saddle-shaped molecules are made. Chapter 1 contains two major parts. The first part reviews polycyclic arenes containing seven-membered carbocycles. A seven-membered ring in polycyclic arenes can stabilize cations by forming the aromatic tropylium ion and may also induce negative curvature to the pi-backbone depending on fusion mode of the heptagon. The synthesis, properties and application of these carbocycles are reviewed. The second part reviews the synthetic studies of conjugated carbon nano-rings with radially oriented pi orbitals. Chapter 2 presents the synthesis of soluble derivatives of C70H 26 and C70H30, two new saddle-shaped polycyclic arenes containing two heptagons. The common precursor of these two aromatic saddles is a saddle-shaped diketone, which embedded two heptagons into the well-known hexa-peri-hexabenzocoronene (HBC), and whose carbonyl groups are the key in the reactions to extend the polycyclic pi-framework. These compounds are characterized by X-ray crystallography and are shown to be saddle-shaped. On the basis of crystal structures, local aromaticity and nonplanarity of individual rings in the saddle-shaped pi-backbone are analyzed, and are found to follow Clar's rule in general. It is found that two of these compounds behave as p-type semiconductors in solution-processed thin film transistors. Chapter 3 presents the synthetic studies towards heptagon-embedded carbon nano-ring. Carbon nano-rings such as cycloparaphenylenes are of great interest as they are segments of carbon nanotubes. Theoretical studies suggest that toroidal carbon nanotubes can

  20. WETTABILITY STUDIES OF LEAD-FREE SOLDERS

    African Journals Online (AJOL)

    2012-03-01

    . Lead-bearing sol- ders are no longer used in the fabrication of food- processing equipment and the use of lead pipes for drinking water is now discouraged due to the possibility of lead poisoning from drinking water. [1].

  1. Spectroscopic studies on the photochemical decarboxylation mechanisms of synthetic pyrethroids.

    Science.gov (United States)

    Suzuki, Yusuke; Ishizaka, Shoji; Kitamura, Noboru

    2012-12-01

    A novel radical trapping technique combined with a fluorescence spectroscopic analysis has been employed to investigate the radical intermediates produced by photodecarboxylation of four synthetic pyrethroids: fenvalerate (SMD), fenpropathrin (DTL), cyphenothrin (GKL), and cypermethrin (AGT). Under photoirradiation at >290 nm, all pyrethroids underwent direct photolysis via homolytic cleavage of the carbon-oxygen bonds in the ester groups. The consumed amount of a nitroxide free radical, as a trapping agent for the intermediate radical of a pyrethroid, was determined by ESR, which was the measure of the reaction yield of a photochemically generated α-cyano-3-phenoxybenzyl radical common to all pyrethroids. The reactivities of the pyrethroids studied was in the sequence of SMD > DTL > GKL > AGT. Furthermore, nanosecond transient absorption spectroscopy demonstrated that geminate recombination of the radical pair within a solvent cage is the main deactivation route of the photochemically generated α-cyano-3-phenoxybenzyl radical common for all pyrethroids studied.

  2. Vectoring of parallel synthetic jets: A parametric study

    Science.gov (United States)

    Berk, Tim; Gomit, Guillaume; Ganapathisubramani, Bharathram

    2016-11-01

    The vectoring of a pair of parallel synthetic jets can be described using five dimensionless parameters: the aspect ratio of the slots, the Strouhal number, the Reynolds number, the phase difference between the jets and the spacing between the slots. In the present study, the influence of the latter four on the vectoring behaviour of the jets is examined experimentally using particle image velocimetry. Time-averaged velocity maps are used to study the variations in vectoring behaviour for a parametric sweep of each of the four parameters independently. A topological map is constructed for the full four-dimensional parameter space. The vectoring behaviour is described both qualitatively and quantitatively. A vectoring mechanism is proposed, based on measured vortex positions. We acknowledge the financial support from the European Research Council (ERC Grant Agreement No. 277472).

  3. Synthetic fibre reinforcement of absorptive glass-mat separators for valve-regulated lead-acid batteries

    Science.gov (United States)

    Simarro, R.

    The contribution of synthetic fibres to the puncture resistance of absorptive glass-mat (AGM) battery separators when they are combined with glass microfibres is presented. Other mechanical characteristics necessary for the automated manufacture of batteries are also improved by the addition of well-chosen synthetic fibres. The selection of these synthetic fibres is of paramount importance given that specific physical parameters such as wicking, porosity or wettability have to be taken into account to design a useful and long-life AGM battery separator.

  4. Comparative study of the electronic structure of natural and synthetic ...

    Indian Academy of Sciences (India)

    Unknown

    Kenya, etc. Synthetic ruby due to the low cost mass pro- duction is also available. Therefore, there is a commer- cial demand to distinguish a precious natural ruby from the artificial (synthetic) ruby. Some of the known methods for identification of gemstones utilize the knowledge of refractive index (RI), specific gravity (SG), ...

  5. Structural and Functional Studies of Experimental HIV Synthetic Peptides Immunogens.

    Science.gov (United States)

    1998-09-01

    Work performed in this grant continues to address major hurdles in the development of an effective synthetic peptide HIV vaccine: 1) the ability of...isolates and 2) the design of synthetic peptide immunogens capable of being recognized by MHC Class I and II molecules in outbred populations. In

  6. Synthetic Peptides as Receptors in Affinity Sensors: A Feasibility Study

    NARCIS (Netherlands)

    van den Heuvel, D.J.; van den Heuvel, Dave J.; Kooyman, R.P.H.; Drijfhout, Jan Wouter; Welling, Gjalt W.

    1993-01-01

    A relatively simple method for immobilizing synthetic peptides as a receptor onto a gold surface using the self-assembling monolayer (SAM) technique has been investigated. A synthetic peptide with an amino acid sequence similar to the 9-21 gD sequence of herpes simplex virus type 1 was modified with

  7. Lead

    Science.gov (United States)

    ... about the health effects of lead in drinking water The law mandates no-lead products for drinking water after ... Waste, and Cleanup Lead Mold Pesticides Radon Science Water A-Z Index Laws & Regulations By Business Sector By Topic Compliance Enforcement ...

  8. WETTABILITY STUDIES OF LEAD-FREE SOLDERS

    African Journals Online (AJOL)

    2012-03-01

    Mar 1, 2012 ... produced and characterized for possible replacement of Tin-Lead solders. The solder alloys produced are: 91Sn–9Zn, 60Sn–40Zn, 42Sn–58Bi, and 90Sn–10Bi. Tin-lead ... processing equipment and the use of lead pipes for drinking water is now discouraged due to the possibility of lead poisoning from ...

  9. The relevance of polymeric synthetic membranes in topical formulation assessment and drug diffusion study.

    Science.gov (United States)

    Ng, Shiow-Fern; Rouse, Jennifer J; Sanderson, Francis D; Eccleston, Gillian M

    2012-03-01

    Synthetic membranes are composed of thin sheets of polymeric macromolecules that can control the passage of components through them. Generally, synthetic membranes used in drug diffusion studies have one of two functions: skin simulation or quality control. Synthetic membranes for skin simulation, such as the silicone-based membranes polydimethylsiloxane and Carbosil, are generally hydrophobic and rate limiting, imitating the stratum corneum. In contrast, synthetic membranes for quality control, such as cellulose esters and polysulfone, are required to act as a support rather than a barrier. These synthetic membranes also often contain pores; hence, they are called porous membranes. The significance of Franz diffusion studies and synthetic membranes in quality control studies involves an understanding of the fundamentals of synthetic membranes. This article provides a general overview of synthetic membranes, including a brief background of the history and the common applications of synthetic membranes. This review then explores the types of synthetic membranes, the transport mechanisms across them, and their relevance in choosing a synthetic membrane in Franz diffusion cell studies for formulation assessment purposes.

  10. Jewellery: alloy composition and release of nickel, cobalt and lead assessed with the EU synthetic sweat method.

    Science.gov (United States)

    Hamann, Dathan; Thyssen, Jacob P; Hamann, Carsten R; Hamann, Curtis; Menné, Torkil; Johansen, Jeanne D; Spiewak, Radoslaw; Maibach, Howard; Lundgren, Lennart; Lidén, Carola

    2015-10-01

    Several studies have shown nickel and cobalt release from jewellery by using spot tests, but the metal composition of jewellery is largely unknown. To evaluate the metal composition of a large worldwide sample of mainly inexpensive jewellery items, and investigate the release of nickel, cobalt and lead from a subsample by using EN 1811:1998-required methods. A total of 956 metallic jewellery components were examined with X-ray fluorescence spectroscopy. A subsample of 96 jewellery items purchased in the United States were investigated for nickel, cobalt and lead release by the use of artificial sweat immersion and plasma optical emission spectroscopy. Eighteen elements were detected. The 10 most frequently occurring were, in order of frequency, copper, iron, zinc, nickel, silver, chromium, tin, manganese, lead, and cobalt. Release of nickel was noted from 79 of the 96 US samples (0.01-98 µg/cm(2) /week), release of cobalt from 35 samples (0.02-0.5 µg/cm(2) /week), and release of lead from 37 samples (0.03-2718 µg/cm(2) /week). We present here a comprehensive list of the most frequently encountered metals in jewellery and fashion accessories. Different allergenic and non-allergenic metals are utilized. We also report the frequent release of nickel, cobalt and lead from these objects, despite legislative restrictions. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  11. Autonomy and Fear of Synthetic Biology: How Can Patients' Autonomy Be Enhanced in the Field of Synthetic Biology? A Qualitative Study with Stable Patients.

    Science.gov (United States)

    Rakic, Milenko; Wienand, Isabelle; Shaw, David; Nast, Rebecca; Elger, Bernice S

    2017-04-01

    We analyzed stable patients' views regarding synthetic biology in general, the medical application of synthetic biology, and their potential participation in trials of synthetic biology in particular. The aim of the study was to find out whether patients' views and preferences change after receiving more detailed information about synthetic biology and its clinical applications. The qualitative study was carried out with a purposive sample of 36 stable patients, who suffered from diabetes or gout. Interviews were transcribed verbatim, translated and fully anonymized. Thematic analysis was applied in order to examine stable patients' attitudes towards synthetic biology, its medical application, and their participation in trials. When patients were asked about synthetic biology in general, most of them were anxious that something uncontrollable could be created. After a concrete example of possible future treatment options, patients started to see synthetic biology in a more positive way. Our study constitutes an important first empirical insight into stable patients' views on synthetic biology and into the kind of fears triggered by the term "synthetic biology." Our results show that clear and concrete information can change patients' initial negative feelings towards synthetic biology. Information should thus be transmitted with great accuracy and transparency in order to reduce irrational fears of patients and to minimize the risk that researchers present facts too positively for the purposes of persuading patients to participate in clinical trials. Potential participants need to be adequately informed in order to be able to autonomously decide whether to participate in human subject research involving synthetic biology.

  12. Moessbauer Study of Discoloration of Synthetic Resin Covered Electric Switches

    International Nuclear Information System (INIS)

    Kuzmann, E.; Muzsay, I.; Homonnay, Z.; Vertes, A.

    2002-01-01

    57 Fe Moessbauer spectroscopy and X-ray diffractometry were used to investigate brown discoloration and sediments formed on the surface of synthetic resin product covered electronic switches. The Moessbauer measurement revealed that alloyed steels and iron-containing corrosion products are associated with the discolored layers. Iron, and iron corrosion products were shown by both MS and XRD in the sediments formed eventually during the finishing of the synthetic resin products after machining and washing with water solution.

  13. Spectroscopy Study of Synthetic Forsterite Obtained from Zeolite Precursors

    Directory of Open Access Journals (Sweden)

    Subotić, B.

    2008-02-01

    Full Text Available Important ceramics materials are prepared from aluminosilicate based precursors using novel methods, offering at the same time a better control over many important properties. Forsterite, due to its good refractoriness with melting point at 2163 K, excellent electrical insulation properties even at high temperatures, low dielectric permittivity, thermal expansion and chemical stability, is a material of interest to engineers and designers especially as an active medium for tuneable laser and is also a material of interest to SOFC (Solid oxide fuel cells manufacturers. The aim of this study is to investigate the synthesis of crystalline forsterite using different zeolite precursors previously activated by ball milling. Synthetic forsterite was synthesized from different zeolite precursors and MgO combining highenergy ball milling and thermal treatment of the mixture under determined conditions of time and temperature for each operation. In this research are studied the solid-state phase transformations taking place at temperatures below 1273 K. The obtained products were characterized using different spectroscopy techniques in comparison with surface analysis method and X-ray diffraction.

  14. The relationship between environmental lead and blood lead in children : a study in environmental epidemiology

    OpenAIRE

    Brunekreef, B.

    1985-01-01

    This study deals with the relationship between environmental lead and blood lead in children.
    Chapter 1 provides a summary of the environmental health aspects of lead. The occurrence of lead in the environment and in man is described; children are discussed as a population at risk for undue lead absorption, and the exposure-response system is briefly outlined.
    Chapter 2 discusses a number of methodological issues in studies on the relationship between environment...

  15. The relationship between environmental lead and blood lead in children : a study in environmental epidemiology

    NARCIS (Netherlands)

    Brunekreef, B.

    1985-01-01

    This study deals with the relationship between environmental lead and blood lead in children.
    Chapter 1 provides a summary of the environmental health aspects of lead. The occurrence of lead in the environment and in man is described; children are discussed as a population at

  16. Problem Definition Study: Lead Beta-Resorcylate

    Science.gov (United States)

    1979-02-01

    Cornell, R.P. and Filkins, J.P. (1974) "Depression of Hepatic Gluconeogenesis * by Acute Lead Administration," Proc. Soc. Exp. Biol. lied., 147(2...Klaassen, CD. and Shoeman, D.W. (1974), "Biliary Excretion of Lead in Cats, Rabbits, and Dogs ," toxicol. Arpl. Pharmacol., 29(3), 434-446. -48

  17. A study of porosity of synthetic polymer nanoparticles using PALS

    Energy Technology Data Exchange (ETDEWEB)

    Pham, B; Smith, S V [Centre for Antimatter-Matter Studies, Australian Nuclear Science and Technology Organisation (ANSTO) NSW 2232 (Australia); Guagliardo, P; Williams, J; Samarin, S, E-mail: binh.pham@ansto.gov.au, E-mail: svs@ansto.gov.au [Centre for Antimatter-Matter Studies, School of Physics, University of Western Australia, WA 6009 (Australia)

    2011-01-01

    Positron annihilation lifetime spectroscopy (PALS) has been used to study the free volume in dry synthetic polymer nanoparticles of various sizes. A series of poly(styrene/divinyl benzene) particles with diameters in the range of 100 to 500 nm were synthesized and then carefully chemically treated using the sulfonation process, to increase their porosity. The particles were characterised by Scanning Electron Microscopy (SEM), light scattering and PALS. Light scattering gave larger size for the treated particles, reflecting the hydration effect and therefore the increase in porosity. PALS spectra of untreated and treated particles gave four and three life-time components, respectively. Analysis by PAScual version 1.3.0 program indicated there was a reduction in the intensity and the type of the micropores in the treated particles. The data suggest PALS is a sensitive tool for detecting changes in microporosity in particles. The conflicting results obtained for light scattering compared to PALS for chemically treated particles is difficult to resolve and suggests sample preparation of polymeric materials for PALS is the critical factor.

  18. Optically stimulated luminescence (OSL) study of synthetic stishovite

    International Nuclear Information System (INIS)

    Tani, A.; Yamanaka, C.; Ikeya, M.; Ohtaka, O.; Takada, M.; Katsura, T.

    2000-01-01

    Optically stimulated luminescence (OSL) of synthetic stishovite was investigated for a future dating technique of meteor impact craters. Luminescence around 330 nm was measured on the γ-ray irradiated stishovite under two stimulating light sources of infrared laser (830 nm) and blue light emitting diode set (470 nm). Thermoluminescence (TL) studies before and after the OSL measurements showed the intensities around 100-200 deg. C and 220-350 deg. C to increase and those around 350-450 deg. C to decrease. This indicates that a part of deep-trapped charges excited during the OSL measurements were retrapped by shallower traps. The infrared stimulated luminescence (IRSL) after the TL measurement up to 450 deg. C could not be detected, while the blue light stimulated luminescence (BLSL) after TL had about one-tenth of the intensity before TL. This indicates that a part of the charges in shallower traps were detrapped thermally and returned to the deeper traps which were related to BLSL. The result implies that some of the BLSL-related traps are quite stable at room temperature and could be used for geological dating. In addition, two paramagnetic centers produced by sudden release of high pressure in synthesis process were found in the unirradiated stishovite by electron spin resonance (ESR). Their g-factors are g parallel =2.00181 and g perpendicular =2.00062 for an axial signal and g=2.00305 for the other isotropic signal. These signals could be used for an evidence of impacts if those signals could be stored in geological time

  19. Spectroscopic study of synthetic hydrothermal Fe3+-bearing beryl

    Science.gov (United States)

    Taran, Michail N.; Dyar, M. Darby; Khomenko, Vladimir M.

    2017-12-01

    A synthetic hydrothermal beryl Fe-4-51, investigated previously by Taran and Rossman (Am Miner 86:973-980, 2001), was additionally studied by microprobe, Mössbauer, optical absorption, Raman and IR spectroscopy. For comparison, polarized spectra of natural blue aquamarine and Cr3+, Fe3+-bearing alexandrite, both from Brazil, are also presented. Fe-4-51 is a nearly pure Fe3+-bearing beryl, with a homogeneous composition as shown by electron microprobe. Averaging over 22 points gives a formula of Be3.07(Al1.94,{Fe}_{{{0.07}}}^{{{3}+}} )Σ=2.01Si5.95O18, with Fe3+ replacing Al3+ in the octahedral site of the structure. The Mössbauer spectrum is dominated by a broad disordered pattern with beryl-suitable parameters; for Fe2+, IS = 1.21 mm/s, QS = 2.71 mm/s, area ≈ 5% and for Fe3+, IS = 0.34 mm/s, QS = 0.71 mm/s, and area ≈ 67%—are distinguished overlying a broad disordered continuum. The optical absorption spectrum is typical of octahedral Fe3+. From it, the crystal field strength Dq is derived as 1520 cm-1 and the values of Racah parameters of interelectronic repulsion B and C are found to be 665 and 3415 cm-1, respectively. This rather low B value, compared with that of a free Fe3+ ion, 814 cm-1, suggests a comparatively high degree of covalency in the octahedral Fe3+-O bond. Infrared spectra show the presence of channel H2O of both I and II structural type in comparable quantities, about 0.5 and 1 mass%, respectively. Raman data show the expected five bands in the energy range from 300 to 1200 cm-1.

  20. Improving Order Lead Time: A Case Study

    Science.gov (United States)

    Villarreal, Bernardo; Salido, Lucy

    2009-01-01

    A fundamental challenge of globally competing companies is to increase their level of customer satisfaction, by devising and implementing strategies aimed at providing better price, quality, and service. This paper describes the efforts of a Mexican company to achieve this goal, and in particular, with the need to decrease order lead time…

  1. Synthetic food colourings and 'hyperactivity': a double-blind crossover study.

    Science.gov (United States)

    Rowe, K S

    1988-04-01

    Of 220 children referred for suspected 'hyperactivity', 55 were subjected to a 6 week trial of the Feingold diet. Forty (72.7%) demonstrated improved behaviour and 26 (47.3%) remained improved following liberalization of the diet over a period of 3-6 months. The parents of 14 children claimed that a particular cluster of behaviours was associated with the ingestion of foods containing synthetic colourings. A double-blind crossover study, employing a single-subject repeated measures design was conducted, using eight of these children. Subjects were maintained on a diet free from synthetic additives and were challenged daily for 18 weeks with either placebo (during lead-in and washout periods) or 50 mg of either tartrazine or carmoisine, each for 2 separate weeks. Two significant reactors were identified whose behavioural pattern featured extreme irritability, restlessness and sleep disturbance. One of the reactors did not have inattention as a feature. The findings raise the issue of whether the strict criteria for inclusion in studies concerned with 'hyperactivity' based on 'attention deficit disorder' may miss children who indicate behavioural changes associated with the ingestion of food colourings. Moreover, for further studies, the need to construct a behavioural rating instrument specifically validated for dye challenge is suggested.

  2. Morphology and thermal degradation study of poly(lactic acid)/synthetic mica composites

    International Nuclear Information System (INIS)

    Souza, D.H.S.; Dias, M.L.

    2010-01-01

    Poly(lactic acid) (PLA)/synthetic mica composites has been little studied in the literature. In this work, an organophilic synthetic mica was used to prepare PLA nanocomposites. The composites were obtained at an internal mixer containing 3, 5, 7 and 10 wt% of mica. The materials were analyzed by x-ray diffraction, thermogravimetric analysis and gel permeation chromatography. (author)

  3. DROP AMALGAM VOLTAMMETRIC STUDY OF LEAD ...

    African Journals Online (AJOL)

    a

    Lake, sea and river waters contain trace metals such as copper, zinc, cadmium and lead whose ... methods [11, 12]. The equation. I = ½∑CiZi. 2. (1) was used to calculate the ionic strength (I) of the lake water. Ci is the concentration of the ion I while Zi is its charge, the value obtained for the ionic strength was 7.35 M.

  4. Modulation of synthetic parameters of cobalt nanoparticles: TEM, EDS, spectral and thermal studies

    Science.gov (United States)

    Chandra, Sulekh; Kumar, Avdhesh

    2012-12-01

    The study focuses on the modulation of synthetic parameters in order to influence the size, structure, composition and arrangement of nanoparticles of cobalt. Cobalt nanoparticles were synthesized by ethanolic solution of benzildiethylenetriamine in cobalt nitrate solution at 60 °C with stirring and refluxing leads to nanoparticles of cobalt. The morphology and structure of the synthesized nanoparticles of cobalt were characterized by Transmission Electron Microscopy (TEM), Powder X-ray Diffraction (XRD), Thermal Gravimetric Analysis (TGA), QELS Data and Infrared Spectroscopy (IR). Crystalline size was 20 nm determined from the sharp peak at 2θ = 25 °C from the powder XRD. TEM images of cobalt nanoparticles without reducing agent having the diameter 20 nm with spherical shape and black color.

  5. Study of Wide Swath Synthetic Aperture Ladar Imaging Techology

    Directory of Open Access Journals (Sweden)

    Zhang Keshu

    2017-02-01

    Full Text Available Combining synthetic-aperture imaging and coherent-light detection technology, the weak signal identification capacity of Synthetic Aperture Ladar (SAL reaches the photo level, and the image resolution exceeds the diffraction limit of the telescope to obtain high-resolution images irrespective to ranges. This paper introduces SAL, including the development path, technology characteristics, and the restriction of imaging swath. On the basis of this, we propose to integrate the SAL technology for extending its swath. By analyzing the scanning-operation mode and the signal model, the paper explicitly proposes that the former mode will be the developmental trend of the SAL technology. This paper also introduces the flight demonstrations of the SAL and the imaging results of remote targets, showing the potential of the SAL in long-range, high-resolution, and scanning-imaging applications. The technology and the theory of the scanning mode of SAL compensates for the defects related to the swath and operation efficiency of the current SAL. It provides scientific foundation for the SAL system applied in wide swath, high resolution earth observation, and the ISAL system applied in space-targets imaging.

  6. [Study on lead absorption in pumpkin by atomic absorption spectrophotometry].

    Science.gov (United States)

    Li, Zhen-Xia; Sun, Yong-Dong; Chen, Bi-Hua; Li, Xin-Zheng

    2008-07-01

    A study was carried out on the characteristic of lead absorption in pumpkin via atomic absorption spectrophotometer. The results showed that lead absorption amount in pumpkin increased with time, but the absorption rate decreased with time; And the lead absorption amount reached the peak in pH 7. Lead and cadmium have similar characteristic of absorption in pumpkin.

  7. Synthetic Cannabinoids

    Directory of Open Access Journals (Sweden)

    Aslihan Okan Ibiloglu

    2017-09-01

    Full Text Available Synthetic cannabinoids which is a subgroup of cannabinoids are commonly used for recreational drug use throughout the whole world. Although both marijuana and synthetic cannabinoids stimulate the same receptors, cannabinoid receptor 1 (CB1 and cannabinoid receptor 2 (CB2, studies have shown that synthetic cannabinoids are much more potent than marijuana. The longer use of synthetic cannabinoids can cause severe physical and psychological symptoms that might even result in death, similar to many known illicit drugs. Main treatment options mostly involve symptom management and supportive care. The aim of this article is to discuss clinical and pharmacological properties of the increasingly used synthetic cannabinoids. [Psikiyatride Guncel Yaklasimlar - Current Approaches in Psychiatry 2017; 9(3.000: 317-328

  8. Elastic FWI for VTI media: A synthetic parameterization study

    KAUST Repository

    Kamath, Nishant

    2016-09-06

    A major challenge for multiparameter full-waveform inversion (FWI) is the inherent trade-offs (or cross-talk) between model parameters. Here, we perform FWI of multicomponent data generated for a synthetic VTI (transversely isotropic with a vertical symmetry axis) model based on a geologic section of the Valhall field. A horizontal displacement source, which excites intensive shear waves in the conventional offset range, helps provide more accurate updates to the SV-wave vertical velocity. We test three model parameterizations, which exhibit different radiation patterns and, therefore, create different parameter trade-offs. The results show that the choice of parameterization for FWI depends on the availability of long-offset data, the quality of the initial model for the anisotropy coefficients, and the parameter that needs to be resolved with the highest accuracy.

  9. Fixation of tibial plateau fractures with synthetic bone graft versus natural bone graft: a comparison study.

    LENUS (Irish Health Repository)

    Ong, J C Y

    2012-06-01

    The goal of this study was to determine differences in fracture stability and functional outcome between synthetic bone graft and natural bone graft with internal fixation of tibia plateau metaphyseal defects.

  10. A Theoretical Study of Leading Edge Noise

    Science.gov (United States)

    2008-05-01

    measurements of the noise radiated from a number of different airfoils made as -part of a companion study at Virginia lech . It was concluded that the...giving, at a distance r from the blade, and at an angle 9 to the direction of the unsteady loading, the sound spectrum as Spp(co)=( cocos &4itrcc) 2SLL

  11. Studies on the specificity of immunological reactions of synthetic and natural Thomsen-Friedenreich antigens

    International Nuclear Information System (INIS)

    Hoeppner, W.

    1982-01-01

    A number of derivatives of disaccharide β-D-Gal-(1,3)-D-GalNAc, the carbohydrate component of T-antigen, and four different synthetic antigens having this disaccharide structure have been investigated. The immunological reactions with native human antibodies and rabbit immune antibodies have been studied in the haemagglutination inhibition test and in RIA. The findings are relevant to the use of synthetic carbohydrate antigens as model substances for immunological studies. (orig./MG) [de

  12. Using XAFS, EDAX and AFM in comparative study of various natural and synthetic emeralds

    International Nuclear Information System (INIS)

    Parikh, P.; Saini, N.L.; Dalela, S.; Bhardwaj, D.M.; Fernandes, S.; Gupta, R.P.; Garg, K.B.

    2003-01-01

    We have performed XAFS, EDAX and AFM studies on some natural and synthetic emeralds. While the XAFS results yield information on changes in the valence of the Cr ion and the n-n distance the AFM is used to determine the areal atomic density on surface of the crystals. It is a pilot study to explore if the three techniques can offer a possible way of distinguishing between the natural and synthetic emeralds and the results are promising

  13. A follow-up study of women in the synthetic rubber industry: study methods.

    Science.gov (United States)

    Sathiakumar, Nalini; Delzell, Elizabeth

    2007-03-20

    Concerns about the possible toxic effects of workplace exposures in the synthetic rubber industry have centered on 1,3-butadiene (BD), styrene and dimethyldithiocarbamate (DMDTC). Our previous mortality studies of over 17,000 male synthetic rubber workers found an excess of leukemia that may be due to BD or BD plus other chemicals. Experimental studies have shown that BD produces mammary tumors in female mice and rats and ovarian tumors in female mice. This paper presents the methods of a follow-up study that evaluates the mortality experience of women employed in the North American synthetic rubber industry. Women employed for at least 1 day at any of eight North American styrene-butadiene rubber plants were followed up from 1943 to 2002. Identifying and work history information were obtained from personnel records. Estimated quantitative exposure to BD, styrene and DMDTC, developed for our previous study of men, were used in this study. External analyses use the standardized mortality ratios (SMRs) to compare the cohort's cause-specific mortality rates to the rates of the female general population of the states or the province where the plants are located. Internal analyses use the Poisson regression and Cox proportional hazards models to examine specific cancer mortality rates in relation to BD, styrene and DMDTC exposure, by comparing an exposed cohort subgroup with the rate of unexposed cohort members.

  14. Systems studies of dual purpose electric/synthetic fuels fusion plants

    International Nuclear Information System (INIS)

    Beardsworth, E.; Powell, J.

    1975-02-01

    A reactor power plant is proposed that can meet base load electrical demand, while the remainder can generate synthetic fuels and meet intermittent electrical demands. Two principal objectives of this study are: (1) to examine how strongly various economic demand and resource factors affect the amount of installed CTR capacity, and (2) to examine what increase in CTR capacity can be expected with dual purpose electric/synthetic fuel fusion plants, and also the relative importance of the different production modes

  15. Lead preconcentration in synthetic samples with triton x-114 in the cloud point extraction and analysis by atomic absorption (EAAF)

    International Nuclear Information System (INIS)

    Zegarra Pisconti, Marixa; Cjuno Huanca, Jesus

    2015-01-01

    A methodology was developed about lead preconcentration in water samples that were added dithizone as complexing agent, previously dissolved in the nonionic surfactant Triton X-114, until the formation of the critical micelle concentration and the cloud point temperature. The centrifuged system gave a precipitate with high concentrations of Pb (II) that was measured by atomic absorption spectroscopy with flame (EAAF). The method has proved feasible to be implemented as a method of preconcentration and analysis of Pb in aqueous samples with concentrations less than 1 ppm. Several parameters were evaluated to obtain a percentage recovery of 89.8%. (author)

  16. Full-thickness skin graft vs. synthetic mesh in the repair of giant incisional hernia: a randomized controlled multicenter study.

    Science.gov (United States)

    Clay, L; Stark, B; Gunnarsson, U; Strigård, K

    2018-04-01

    Repair of large incisional hernias includes the implantation of a synthetic mesh, but this may lead to pain, stiffness, infection and enterocutaneous fistulae. Autologous full-thickness skin graft as on-lay reinforcement has been tested in eight high-risk patients in a proof-of-concept study, with satisfactory results. In this multicenter randomized study, the use of skin graft was compared to synthetic mesh in giant ventral hernia repair. Non-smoking patients with a ventral hernia > 10 cm wide were randomized to repair using an on-lay autologous full-thickness skin graft or a synthetic mesh. The primary endpoint was surgical site complications during the first 3 months. A secondary endpoint was patient comfort. Fifty-three patients were included. Clinical evaluation was performed at a 3-month follow-up appointment. There were fewer patients in the skin graft group reporting discomfort: 3 (13%) vs. 12 (43%) (p = 0.016). Skin graft patients had less pain and a better general improvement. No difference was seen regarding seroma; 13 (54%) vs. 13 (46%), or subcutaneous wound infection; 5 (20%) vs. 7 (25%). One recurrence appeared in each group. Three patients in the skin graft group and two in the synthetic mesh group were admitted to the intensive care unit. No difference was seen for the primary endpoint short-term surgical complication. Full-thickness skin graft appears to be a reliable material for ventral hernia repair producing no more complications than when using synthetic mesh. Patients repaired with a skin graft have less subjective abdominal wall symptoms.

  17. [Study on the vibrational spectra characterization of synthetic jadeite jade made by General electric Company].

    Science.gov (United States)

    Cao, Shu-Min; Qi, Li-Jian; Guo, Qing-Hong; Zhong, Zeng-Qiu; Qiu, Zhi-Li; Li, Zhi-Gang

    2008-04-01

    The object of the present study is the synthetic jadeite jade produced by American General Electric Corporation. Fourier transform infrared spectroscopy (FTIR) and Laser Raman spectroscopy were used to test its spectral properties in order to examine the feature of this kind of synthetic jadeite jade by vibrational spectroscopy and to figure out the mark for discriminate synthetic jadeite jade from natural jadeite jade. The study shows that GE synthetic jadeite jade is identical with natural jadeite jade in the main on fingerprint region in FTIR; There are clearly differences in the 2 000 -4 000 cm(-1) functional region in FTIR: a group of frequencies at 3 375, 3 471 and 3 614 cm(-1) indicate vibration absorption of O-H. GE synthetic jadeite jade has proven consistent with natural jadeite jade in the laser Raman spectra by a group of sharp scattering peaks at 376, 700, 989 and 1 039 cm(-1). In addition these scattering peaks show an intact crystal shape. The FTIR peaks and Raman spectral peaks shift to higher frequencies showing GE synthetic jadeite jade lacking isomorphism of heavy positive ions.

  18. Experimental study on the use of synthetic jet actuators for lift control

    Science.gov (United States)

    Torres, Ricardo Benjamin

    An experimental study on the use of synthetic jet actuators for lift control is conducted. The synthetic jet actuator is placed on the pressure side towards the trailing edge on a NACA 65(2)-415 airfoil representative of the cross section of an Inlet Guide Vane (IGV) in an industrial gas compressor. By redirecting or vectoring the shear layer at the trailing edge, the synthetic jet actuator increases lift and decreases drag on the airfoil without a mechanical device or flap. A compressor map that defines upper and lower bounds on operating velocities and airfoil dimensions, is compared with operating conditions of the low-speed wind tunnel at San Diego State University, to match gas compressor conditions in the wind tunnel. Realistic test conditions can range from Mach=0.12 to Mach= 0.27 and an airfoil chord from c=0.1 m to c=0.3 m. Based on the operating conditions, a final airfoil model is fabricated with a chord of c=0.1m. Several synthetic jet actuator designs are considered. A initial synthetic jet is designed to house a piezoelectric element with a material frequency of 1200 hz in a cavity with a volume of 4.47 cm3, a slot width of 0.25 mm, and a slot depth of 1.5 mm. With these dimensions, the Helmholtz frequency of the design is 1800Hz. Particle Image Velocimetry (PIV) experiments show that the design has a jet with a peak centerline jet velocity of 26 m/s at 750 Hz. A modified slant face synthetic jet is designed so that the cavity fits flush within the NACA airfoil surface. The slanted synthetic jet has a cavity volume of 4.67 cm3, a slot width of 0.25 mm, and a slot depth of 3.45 mm resulting in a Helmholtz frequency of 1170 hz for this design. PIV experiments show that the jet is redirected along the slant face according to the Coanda effect. A final synthetic jet actuator is directly integrated into the trailing edge of an airfoil with a cavity volume of 4.6 cm3, a slot width of 0.2 mm, and a slot depth of 1.6 mm. The Helmholtz frequency is 1450 Hz and

  19. Atomic force microscopy analysis of synthetic membranes applied in release studies

    International Nuclear Information System (INIS)

    Olejnik, Anna; Nowak, Izabela

    2015-01-01

    Graphical abstract: - Highlights: • We compare eight synthetic membranes by atomic force microscopy. • We predict the behavior of membranes in the release experiments. • The polymeric synthetic membranes varied in shape and size. • We detect substructures in pores of cellulose esters and nylon membranes. • Substructures limit the release rate of active compound. - Abstract: Synthetic membranes are commonly used in drug release studies and are applied mostly in quality control. They contain pores through which the drug can be diffused directly into the receptor fluid. Investigation of synthetic membranes permits determination of their structure and characterization of their properties. We suggest that the preliminary characterization of the membranes can be relevant to the interpretation of the release results. The aim of this study was to compare eight synthetic membranes by using atomic force microscopy in order to predict and understand their behavior in the release experiments. The results proved that polytetrafluoroethylene membrane was not suitable for the release study of tetrapeptide due to its hydrophobic nature, thickness and the specific structure with high trapezoid shaped blocks. The additional substructures in pores of mixed cellulose esters and nylon membranes detected by AFM influenced the diffusion rate of the active compound. These findings indicate that the selection of the membrane for the release studies should be performed cautiously by taking into consideration the membrane properties and by analyzing them prior the experiment.

  20. A PLIF and PIV study of liquid mixing enhanced by a lateral synthetic jet pair

    International Nuclear Information System (INIS)

    Xia Qingfeng; Zhong Shan

    2012-01-01

    Highlights: ► Enhancement of mixing between two water streams in a planar channel by means of a lateral synthetic jet pair is studied using PLIF and PIV. ► The excellent mixing observed is largely caused by a strong interaction between the opposing vortex pairs produced by the lateral synthetic jets. ► The synthetic jet operating conditions, at which a nearly homogenous mixing is achieved, are also identified and they are expressed in terms of a functional relationship. - Abstract: In this paper, enhancement of mixing between two water streams of the same flow rate in a planar channel by means of a lateral synthetic jet pair is studied at a net flow Reynolds number of 83 using PLIF and PIV. The synthetic jet pair is operated 180° out-of-phase at a range of actuation frequencies and displacements, with the latter being characterized by the dimensionless stroke length. The extent of mixing is evaluated using PLIF data at a location further downstream in the mixing channel. It is found that at a fixed actuation frequency a higher dimensionless stroke length produces a better mixing, and as the actuation frequency increases a lower dimensionless stroke length is required to achieve a given mixing degree. At a sufficiently high frequency or dimensionless stroke length, a nearly homogenous mixing with a mixing degree greater than 0.9 can be obtained. A functional relationship between actuation frequency and dimensionless stroke length is also obtained by best fitting the experimental data, which can be used for selecting the synthetic jet operating conditions to ensure a good mixing. Furthermore, both PLIF and PIV results show that each synthetic jet actuation cycle produce two opposing vortex pairs, which play an important role in prompting mixing between the two fluid streams. The excellent mixing obtained at a high frequency or a high dimensionless stroke length is found to be largely caused by a strong interaction between these opposing vortex pairs.

  1. Study on bioremediation of Lead by exopolysaccharide producing metallophilic bacterium isolated from extreme habitat

    Directory of Open Access Journals (Sweden)

    Debajit Kalita

    2017-12-01

    Full Text Available Lead released from manufacturing factories, recycling plants, automobile company and landfill leachate is abundantly found in wastewater. An efficient bioremediating agent for lead removal from wastewater is expected to ease the ever increasing problem. The present study reports Pseudomonas sp. W6 isolated from extreme habitat of hot water spring of North–East India evaluated for its Lead biosorption property. The bacterium showed capacity to resist 1.0 mM lead in both solid and liquid minimal media. Epifluorescence microscopy reveal the viability of bacterial cells under metal stress condition. ICP-MS analysis revealed 65% and 61.2% removal of lead from the Synthetic Bangladesh Ground Water medium in batch culture and column study respectively which was higher when compared to biosorption capacity of P. aeruginosa MTCC2474, P. alcaligenes MJ7 from forest soil and P. ficuserectae PKRS11 from uranium rich soil. Exopolysaccharide released by the isolate which influenced biosorption revealed the presence of ligands assayed using microbial hydrophobicity and FTIR. The extremophilic isolate is proposed as a choice for efficient bioremediation of lead contaminated wastewater. Keywords: Extremophile, Pseudomonas, Lead bioremediation, Epifluorescence microscopy, ICP-MS, FTIR

  2. Drop amalgam voltammetric study of lead complexation by natural ...

    African Journals Online (AJOL)

    A study of inorganic complexation of lead using drop amalgam voltammetry is described. The study has been carried out in simulated salt lake water and at ionic strength of 7.35 M, the predetermined ionic strength of Lake Katwe. The complexation of lead with the simple ligands (Cl-, CO32-) created anodic waves and the ...

  3. [Comprehensive study of lead pollution in atmospheric aerosol of Shanghai].

    Science.gov (United States)

    Zhang, Gui-lin; Tan, Ming-guang; Li, Xiao-lin; Zhang, Yuan-xun; Yue, Wei-sheng; Chen, Jian-min; Wang, Yin-song; Li, Ai-guo; Li, Yan; Zhang, Yuan-mao; Shan, Zhu-ci

    2006-05-01

    The lead contamination, lead species and source assignment were studied by a combination of several analytical techniques such as Proton-induced X-ray emission analysis (PIXE), Proton microprobe (micro-PIXE), Inductively coupled plasma-mass spectrometry (ICP-MS) and extended X-ray absorption fine structure (EXAFS) techniques. The results indicate that the lead concentration in the air of Shanghai gradually decreased over the last years. The atmospheric lead concentration of PM10 in the winter of 2002 was 369 ng x m(-3), which had declined by 28% in 2001, and in the winter of 2003 it decreased further to 237 ng x m(-3). The main lead species in the samples collected in the winter of 2003 were probably PbCl2, PbSO4 and PbO. The source apportionment was calculated in terms of the combination of lead isotope ratios and lead mass balance method, assisted by single particle analysis with micro-PIXE and pattern recognition. The results suggest that the major contributors of atmospheric lead pollution in Shanghai are the coal combustion dust; the metallurgic dust and vehicle exhaust particles, with a contribution around 50%, 35% and 15%, respectively. It probably is the first time to give a city a quantitative estimation of lead pollution contribution from emission sources. The influence from leaded gasoline was still present in the atmosphere by four or five years after the phasing out of leaded gasoline.

  4. Imouraren mining exploitation : Complementary studies Synthetic report Volum B - Mines

    International Nuclear Information System (INIS)

    1980-01-01

    The object of the current study is to determine the main technical characteristics of the reference project of a mine that can supply the necessary ore quantity at a production of 3000 tonnes uranium per year, along 10 years. The project is one of the possible solutions for exploiting the mine. The current study permits to establish : investment and functioning cost estimation, overall project of the mining exploitation program, necessary strength estimation, average ore grades evaluation and variations of these grades, utilities needs, production vizing program, main exploitation methods and necessary materials. Reference project study of the mine serves as base to the economics studies and studies optimization [fr

  5. Water Availability for Synthetic Fuels: An Assessment of Current Studies

    Science.gov (United States)

    1982-10-01

    The objective of this study is to describe and analyze the hydrologic, : institutional, legal, and economic issues involved in assessing and interpreting : estimates of water availability for synfuels development in four major river : basins: (1) Upp...

  6. Influencing Gameplay in Support of Early Synthetic Prototyping Studies

    Science.gov (United States)

    2016-06-01

    actions of the participant and the performance of artificial intelligence (AI). The study attempted to control unwanted variability from study...Action Review AI Artificial Intelligence AR Army Regulation ARCIC Army Capabilities Integration Center ASA(ALT) Assistant Secretary of the Army...aid worker and are holding him for ransom. Intelligence reports that the hostage is being held in a rebel controlled village to the North of the

  7. Transvenous pacemaker leads in the dog: an experimental study.

    Science.gov (United States)

    Bellenger, C R; Ilkiw, J E; Nicholson, A I; Malik, R; Matthews, R

    1990-09-01

    Tined transvenous pacing leads were inserted into nine healthy large-breed dogs as part of an experimental study evaluating an implantable defibrillator. The pacing leads were used to induce ventricular fibrillation on the day of insertion, two and four weeks after insertion and then monthly. Despite daily running exercise on and off a leash, the tined leads remained firmly anchored to the right ventricular apex for the full experimental period of up to 12 months. Apart from mechanical endocarditis of the tricuspid valve, and partial penetration of the ventricular wall in one dog, problems associated with the pacing leads were not encountered. The use of tined leads and careful technique may minimise the likelihood of transvenous lead displacement.

  8. Six-lead electrocardiographic studies of the pigeon ( Columba livia ...

    African Journals Online (AJOL)

    In this study, the normal electrocardiogram of apparently normal, conscious pigeons was described. Standard bipolar and augmented unipolar limb leads were recorded in a total of apparently healthy 30 pigeons. Waveforms were analyzed in all the leads at 50 mm/s and 10 mm/mV. P-wave was monophasic and positive in ...

  9. Drop amalgam voltammetric study of lead complexation by natural ...

    African Journals Online (AJOL)

    Drop amalgam voltammetric study of lead complexation by natural inorganic ligands in a salt lake. ... Bulletin of the Chemical Society of Ethiopia ... The results obtained indicate that in Lake Katwe water (25 oC, carbonate alkalinity = 0.11 M, pH 11) approximately 0.00% of total inorganic lead exists as the free ion, and at ...

  10. Studies on the biodegradation of natural and synthetic polyethylene ...

    African Journals Online (AJOL)

    Michael Horsfall

    performed for the purpose of biodegradation. The natural or biodegradable polyethylene used in the study was disposable plastic bags containing 6% vegetable starch. The initial and final dry weights of plastic bags before and after incubation in the culture medium were compared and the percentage of degradation was ...

  11. Synthetic Study on the Geological and Hydrogeological Model around KURT

    International Nuclear Information System (INIS)

    Park, Kyung Woo; Kim, Kyung Su; Koh, Yong Kwon; Choi, Jong Won

    2011-01-01

    To characterize the site specific properties of a study area for high-level radioactive waste disposal research in KAERI, the several geological investigations such as surface geological surveys and borehole drillings were carried out since 1997. Especially, KURT (KAERI Underground Research Tunnel) was constructed to understand the further study of geological environments in 2006. As a result, the first geological model of a study area was constructed by using the results of geological investigation. The objective of this research is to construct a hydrogeological model around KURT area on the basis of the geological model. Hydrogeological data which were obtained from in-situ hydraulic tests in the 9 boreholes were estimated to accomplish the objective. And, the hydrogeological properties of the 4 geological elements in the geological model, which were the subsurface weathering zone, the log angle fracture zone, the fracture zones and the bedrock were suggested. The hydrogeological model suggested in this study will be used as input parameters to carry out the groundwater flow modeling as a next step of the site characterization around KURT area

  12. Optical characterization and x-ray diffraction studies of synthetic ...

    African Journals Online (AJOL)

    ... lime and the resulting calcium chloride solution was reacted with dilute sulphuric acid. Calcinations were done at a constant o temperature of 120 C for a period of four hours. The choice of the production parameters was guided by the findings of previous studies. Optical absorption spectra of the samples were measured ...

  13. Study on bioremediation of Lead by exopolysaccharide producing metallophilic bacterium isolated from extreme habitat.

    Science.gov (United States)

    Kalita, Debajit; Joshi, S R

    2017-12-01

    Lead released from manufacturing factories, recycling plants, automobile company and landfill leachate is abundantly found in wastewater. An efficient bioremediating agent for lead removal from wastewater is expected to ease the ever increasing problem. The present study reports Pseudomonas sp. W6 isolated from extreme habitat of hot water spring of North-East India evaluated for its Lead biosorption property. The bacterium showed capacity to resist 1.0 mM lead in both solid and liquid minimal media. Epifluorescence microscopy reveal the viability of bacterial cells under metal stress condition. ICP-MS analysis revealed 65% and 61.2% removal of lead from the Synthetic Bangladesh Ground Water medium in batch culture and column study respectively which was higher when compared to biosorption capacity of P. aeruginosa MTCC 2474, P. alcaligenes MJ7 from forest soil and P. ficuserectae PKRS11 from uranium rich soil. Exopolysaccharide released by the isolate which influenced biosorption revealed the presence of ligands assayed using microbial hydrophobicity and FTIR. The extremophilic isolate is proposed as a choice for efficient bioremediation of lead contaminated wastewater.

  14. Oral two-generation reproduction toxicity study with NM-200 synthetic amorphous silica in Wistar rats

    NARCIS (Netherlands)

    Wolterbeek, A.; Oosterwijk, T.; Schneider, S.; Landsiedel, R.; Groot, D. de; Ee, R. van; Wouters, M.; Sandt, H. van de

    2015-01-01

    Synthetic amorphous silica (SAS) like NM-200 is used in a wide variety of technological applications and consumer products. Although SAS has been widely investigated the available reproductive toxicity studies are old and do not cover all requirements of current OECD Guidelines. As part of a

  15. Pilot study dismantlement of 20 lead-lined shipping casks

    International Nuclear Information System (INIS)

    Thurmond, S.M.

    1995-08-01

    This report describes a pilot study conducted at the INEL to dismantle lead-lined casks and shielding devices, separate the radiologically contaminated and hazardous materials, and recycle resultant scrap lead. The facility areas where the work was performed, dismantlement methods, and process equipment are described. Issues and results associated with recycling the lead as a free-released scrap metal are presented and discussed. Data and results from the pilot study are summarized and presented. The study concluded that cask dismantlement at the INEL can be performed as a legitimate recycling activity for scrap lead. Ninety-one percent of the lead recovered passed free-release criteria. The value of the 50,375 lb of recovered lead is approximately $0.45/lb. Resultant waste streams can be satisfactorily treated and disposed. Only very low levels of bulk radiological contamination (47 picocuries/gram of 137 Cs and 3.2 picocuries/gram of 6O Co) were detected in the lead rejected for free release

  16. Synthetic activity of rat blood lymphocytes under acute and continuous gamma-irradiation - fluorescent microspectral study

    International Nuclear Information System (INIS)

    Karnaukhova, N.A.; Sergiyevich, L.A.; Aksenova, G.Y.; Karnaukhov, V.N.

    1999-01-01

    The effects of different doses of acute and continuous gamma-irradiation on the synthetic activity of rat blood lymphocytes stained with acridine orange were studied by fluorescent microspectrometry. Male rats were exposed to acute gamma-irradiation with doses of 7.5, 4 and 3 Gy, or to continuous irradiation with dose rates of 14.4, 2.1, 1.1 and 0.43 cGy/day, respectively. The changes of the synthetic activity of blood lymphocytes occurred in three main stages after acute gamma-irradiation and in four stages under continuous irradiation. The stages reflect the processes of depression and activation of the immune system under irradiation. Essential differences between the acute and continuous effects were observed in the first stage. After acute gamma-irradiation, the synthetic activity decreased sharply, indicating the predominant contribution of the damaging effect of irradiation, whereas under continuous irradiation, as a result of the stimulatory effect of low-dose irradiation, the synthetic activity increased during the first stage. (orig.)

  17. Spectroscopy study of silver nanoparticles fabrication using synthetic humic substances and their antimicrobial activity

    Science.gov (United States)

    Litvin, Valentina A.; Minaev, Boris F.

    2013-05-01

    In this present study, silver nanoparticles were synthesized using synthetic humic substances (HSs) as reducing and stabilizing agents. Preference of synthetic HSs over natural humic matter is determined by a standardization problem resolution of the product due to the strict control of conditions of the synthetic HSs formation. It allows to receive the silver nanoparticles with the standardized biologically-active protective shell that is very important for their use, mainly in medicine. The concentration of sodium hydroxide, synthetic HSs, silver nitrate and temperature employed in the synthesis process are optimized to attain better yield, controlled size and stability by means of UV-visible technique. In the optimal reaction conditions the concentrated silver colloids (55 mM) with 99.99% yield are obtained which were stable for more than 1 year under ambient conditions. The received silver nanoparticles are characterized by UV-visible spectroscopy, X-ray diffraction (XRD), FT-IR spectroscopy and transmission electron microscopy (TEM). The antimicrobial activity of silver nanoparticles against fungal and bacterial strains is also shown.

  18. CFD Studies on Multi Lead Rifled [MLR] Boiler Tubes

    OpenAIRE

    Dr T C Mohankumar

    2013-01-01

    This paper reports the merits of multi lead rifled [MLR] tubes in vertical water tube boiler using CFD tool. Heat transfer enhancement of MLR tubes was mainly taken in to consideration. Performance of multi lead rifled tube was studied by varying its influencing geometrical parameter like number of rifling, height of rifling, length of pitch of rifling for a particular length. The heat transfer analysis was done at operating conditions of an actual coal fired water tube boiler situated at Apo...

  19. Statistical analysis of lead isotope data in provenance studies

    International Nuclear Information System (INIS)

    Reedy, C.L.

    1991-01-01

    This paper reports on tracing artifacts to ore sources which is different from assigning ore samples to time epochs. Until now, archaeometrists working with lead isotopes have used the ratio methods developed by geochronologists. For provenance studies, however, the use of composition data (the fraction of each of the four isotopes) leads to fewer arbitrary choices, two standard types of plots (labelled ternary and canonical variable, and a consistent method of discriminant analysis for separating groups of samples from different sources

  20. Novel Synthetic Methods and Characterization Studies of Niobium-Disulfide in Multiple Geometries

    Science.gov (United States)

    Cooper, Brian C.

    Since the discovery of graphene, there has been a marked uptick in the rate of research conducted on layered 2D systems. Although much of this work has focused on understanding the properties of the semiconducting members of this group, earnest efforts towards gaining further insight into the physical properties of the non-semiconducting members has also been made. NbS 2, a member of the latter group, offers wide spectrum of physical behavior for study as it undergoes multiple phase transitions from a metal at room temperature to a dual-band superconductor a very. At room temperature this material exhibits metallic character, while at lower temperatures in the range of 30K it undergoes a phase transition to a charge density wave state. It , and that is a undergoes several state transitions within certain temperature regimes Though the effects that quantum constraints impose on Cooper pairs limited to planar transport have been a long established area of research, it has only been in recent years that strides have been made into understanding the nature of quantum confinement on dual-band superconductors. In the contents of this thesis, I provide a thorough account of the development for a novel technique for the synthesis of NbS2 and this technique's evolution through the careful characterization studies performed on the materials resulting from each successive trial. The thesis opens with a brief introduction and relevant historical account of the study of graphene and other 2D layered materials to provide the context from which the reader will understand the motivation for this work. Protocols and parameters developed from the first set of successful experiments, provided the backbone for a reliable synthetic technique for growth of polycrystalline NbS2. The 3R polytype of NbS2 was the overwhelmingly dominant phase within the resultant materials grown during the first trials, but the desire to produce results rich in the 2H-NbS2 polytype prompted a series of

  1. Towards a synthetic chloroplast.

    Directory of Open Access Journals (Sweden)

    Christina M Agapakis

    2011-04-01

    Full Text Available The evolution of eukaryotic cells is widely agreed to have proceeded through a series of endosymbiotic events between larger cells and proteobacteria or cyanobacteria, leading to the formation of mitochondria or chloroplasts, respectively. Engineered endosymbiotic relationships between different species of cells are a valuable tool for synthetic biology, where engineered pathways based on two species could take advantage of the unique abilities of each mutualistic partner.We explored the possibility of using the photosynthetic bacterium Synechococcus elongatus PCC 7942 as a platform for studying evolutionary dynamics and for designing two-species synthetic biological systems. We observed that the cyanobacteria were relatively harmless to eukaryotic host cells compared to Escherichia coli when injected into the embryos of zebrafish, Danio rerio, or taken up by mammalian macrophages. In addition, when engineered with invasin from Yersinia pestis and listeriolysin O from Listeria monocytogenes, S. elongatus was able to invade cultured mammalian cells and divide inside macrophages.Our results show that it is possible to engineer photosynthetic bacteria to invade the cytoplasm of mammalian cells for further engineering and applications in synthetic biology. Engineered invasive but non-pathogenic or immunogenic photosynthetic bacteria have great potential as synthetic biological devices.

  2. The Study of Oxidized Multi-Walled Carbon Nanotubes Efficiency in Lead Removing from Aqueous Solutions

    Directory of Open Access Journals (Sweden)

    M Malakootian

    2015-07-01

    Full Text Available Introduction: Carbon nano tubes are products which have the ability to remove some contaminants from aqueous solutions and wastewater. The efficiency of these products depends on different factors such as PH, concentration, contact, mixing time, etc. in this research the efficiency of oxidized multi- walled carbon nanotubes is studied. Methods: The study is Experimental. The multi-walled carbon nanotubes were oxidized and Three PH 4, 7 and 10 and contact times 5, 10 and 40 min, and the concentrations of 50, 100 and 125 mg of carbon nanotubes from aqueous Pb removal efficiency were examined.All of the tests were done according to the standard methods for the examination of water and wastewater book 21th edited..Real samples of drinking water was the village of Ebrahim Abad RazaviSirjan. Data analysis was done using SPSS statistical software version 16 Results: By Simultaneous changes in time and PH was changed the efficiency of lead removal by the oxidized multi- walled carbon nanotubes. The most important factor in increasing the efficiency of removal, using acidic PH (PH =4 is. With a Simultaneous increase in contact time and concentration of nanotubes, the removal efficiency increased. In optimal conditions, 125 mg of nanotube concentration, contact time of 10 minutes and PH=4 removal of lead in synthetic samples and real samples, respectively, 99.1 and 94% were achieved. In total there is little difference between the real conditions and the synthetic conditions of the removal efficiency that this difference arises from the interaction of cations, anions and heavy metals in real samples. Conclusion: Oxidized multi-walled Carbon nanotubes has a high capacity for the removal of lead from aqueous solutions.

  3. Atomic force microscopy analysis of synthetic membranes applied in release studies

    Science.gov (United States)

    Olejnik, Anna; Nowak, Izabela

    2015-11-01

    Synthetic membranes are commonly used in drug release studies and are applied mostly in quality control. They contain pores through which the drug can be diffused directly into the receptor fluid. Investigation of synthetic membranes permits determination of their structure and characterization of their properties. We suggest that the preliminary characterization of the membranes can be relevant to the interpretation of the release results. The aim of this study was to compare eight synthetic membranes by using atomic force microscopy in order to predict and understand their behavior in the release experiments. The results proved that polytetrafluoroethylene membrane was not suitable for the release study of tetrapeptide due to its hydrophobic nature, thickness and the specific structure with high trapezoid shaped blocks. The additional substructures in pores of mixed cellulose esters and nylon membranes detected by AFM influenced the diffusion rate of the active compound. These findings indicate that the selection of the membrane for the release studies should be performed cautiously by taking into consideration the membrane properties and by analyzing them prior the experiment.

  4. SANS and SAXS Study of Block and Graft Copolymers Containing Natural and Synthetic Rubbers

    Science.gov (United States)

    Hasegawa, H.

    2008-03-01

    Small-angle neutron scattering (SANS) and small-angle X-ray scattering (SAXS) are excellent techniques to study nano-scale concentration fluctuations in the two-component polymer systems such as block and graft copolymers and polymer blends. The miscibility, phase transitions, microphase-separated structures and interface thicknesses were investigated by SANS and SAXS for the block and graft copolymers, which at least contain natural or synthetic rubber as one component.

  5. Studies of Cell-Mediated Immunity Against Immune Disorders Using Synthetic Peptides and Rotating Bioreactor System

    Science.gov (United States)

    Sastry, Jagannadha K.

    1997-01-01

    Our proposed experiments included: (1) immunzing mice with synthetic peptides; (2) preparing spleen and lymph node cells; (3) growing them under conventional conditions as well as in the rotatory vessel in appropriate medium reconstituting with synthetic peptides and/or cytokines as needed; and (4) comparing at regular time intervals the specific CTL activity as well as helper T-cell activity (in terms of both proliferative responses and cytokine production) using established procedures in my laboratory. We further proposed that once we demonstrated the merit of rotatory vessel technology to achieve desired results, these studies would be expanded to include immune cells from non-human primates (rhesus monkeys and chimpanzees) and also humans. We conducted a number of experiments to determine CTL induction by the synthetic peptides corresponding to antigenic proteins in HIV and HPV in different mouse strains that express MHC haplotypes H-2b or H-2d. We immunized mice with 100 ug of the synthetic peptide, suspended in sterile water, and emulsified in CFA (1:1). The immune lymph node cells obtained after 7 days were restimulated by culturing in T25 flask, HARV-10, or STLV-50, in the presence of the peptide at 20 ug/ml. The results from the 5'Cr-release assay consistently revealed complete abrogation of CTL activity of cells grown in the bioreactors (both HARV and STLV), while significant antigen-specific CTL activity was observed with cells cultured in tissue culture flasks. Thus, overall the data we generated in this study proved the usefulness of the NASA-developed developed technology for understanding the known immune deficiency during space travel. Additionally, this ex vivo microgravity technology since it mimics effectively the in vivo situation, it is also useful in understanding immune disorders in general. Thus, our proposed studies in TMC-NASA contract round II application benefit from data generated in this TMC-NASA contract round I study.

  6. Learning through Leading: A Self-Study in District Administration

    Science.gov (United States)

    Collins, Christina

    2016-01-01

    There is little research in the area of understanding educational leaders' psychological processes. This lack of understanding leaves educational leaders to develop their own sense-making practices while in the complex and stressful act of leading. This self-study, conducted over more than half a school year in 2014-2015, was my own effort to do…

  7. A study on precursors leading to geomagnetic storms using artificial ...

    Indian Academy of Sciences (India)

    Space weather prediction involves advance forecasting of the magnitude and onset time of major geomagneticstorms on Earth. In this paper, we discuss the development of an artificial neural network-basedmodel to study the precursor leading to intense and moderate geomagnetic storms, following halo coronalmass ...

  8. Study of Leading Hadrons in Gluon and Quark Fragmentation

    CERN Document Server

    Abdallah, J; Adam, W; Adzic, P; Albrecht, T; Alderweireld, T; Alemany-Fernandez, R; Allmendinger, T; Allport, P P; Amaldi, Ugo; Amapane, N; Amato, S; Anashkin, E; Andreazza, A; Andringa, S; Anjos, N; Antilogus, P; Apel, W D; Arnoud, Y; Ask, S; Augustin, J E; Augustinus, A; Baillon, Paul; Ballestrero, A; Bambade, P; Barbier, R; Bardin, D; Barker, G J; Baroncelli, A; Battaglia, M; Baubillier, M; Becks, K H; Begalli, M; Behrmann, A; Ben-Haim, E; Benekos, N; Benvenuti, A C; Berggren, M; Berntzon, L; Bertrand, D; Besançon, M; Besson, N; Bloch, D; Blom, M; Bluj, M; Bonesini, M; Boonekamp, M; Booth, P S L; Borisov, G; Botner, O; Bouquet, B; Bowcock, T J V; Boyko, I; Bracko, M; Brenner, R; Brodet, E; Brunet, J M; Brückman, P; Buschbeck, B; Buschmann, P; Bérat, C; Calvi, M; Camporesi, T; Canale, V; Carena, F; Castro, N; Cavallo, F; Chapkin, M; Charpentier, P; Checchia, P; Chierici, R; Chudoba, J; Chung, S U; Cieslik, K; Collins, P; Contri, R; Cosme, G; Cossutti, F; Costa, M J; Crennell, D J; Cuevas-Maestro, J; D'Hondt, J; Da Silva, T; Da Silva, W; Dalmau, J; De Angelis, A; De Clercq, C; De Lotto, B; De Maria, N; De Min, A; De Paula, L; Della Ricca, G; Di Ciaccio, L; Di Simone, A; Doroba, K; Drees, J; Eigen, G; Ekelöf, T J C; Ellert, M; Elsing, M; Espirito-Santo, M C; Fanourakis, G K; Fassouliotis, D; Feindt, M; Fernández, J; Ferrer, A; Ferro, F; Flagmeyer, U; Fokitis, E; Fulda-Quenzer, F; Fuster, J; Föth, H; Gandelman, M; García, C; Gavillet, P; Gazis, E; Gokieli, R; Golob, B; Gonçalves, P; Graziani, E; Grosdidier, G; Grzelak, K; Guy, J; Gómez-Ceballos, G; Haag, C; Hallgren, A; Hamacher, K; Hamilton, K; Haug, S; Hauler, F; Hedberg, V; Hennecke, M; Herr, H; Hoffman, J; Holmgren, S O; Holt, P J; Houlden, M A; Jackson, J N; Jarlskog, G; Jarry, P; Jeans, D; Johansson, E K; Johansson, P D; Jonsson, P; Joram, C; Jungermann, L; Kapusta, F; Katsanevas, S; Katsoufis, E; Kernel, G; Kersevan, B P; Kerzel, U; King, B T; Kjaer, N J; Kluit, P; Kokkinias, P; Kourkoumelis, C; Krumshtein, Z; Kucharczyk, M; Kuznetsov, O; Lamsa, J; Leder, G; Ledroit, F; Leinonen, L; Leitner, R; Lemonne, J; Lepeltier, V; Lesiak, T; Liebig, W; Liko, D; Lipniacka, A; Lopes, J H; Loukas, D; Lutz, P; Lyons, L; López, J M; MacNaughton, J; Malek, A; Maltezos, S; Mandl, F; Marco, J; Marco, R; Margoni, M; Marin, J C; Mariotti, C; Markou, A; Martínez-Rivero, C; Maréchal, B; Masik, J; Mastroyiannopoulos, N; Matorras, F; Matteuzzi, C; Mazzucato, F; Mazzucato, M; McNulty, R; Meroni, C; Migliore, E; Mitaroff, W A; Mjörnmark, U; Moa, T; Moch, M; Monge, R; Montenegro, J; Moraes, D; Moreno, S; Morettini, P; Mulders, M; Mundim, L; Murray, W; Muryn, B; Myatt, G; Myklebust, T; Mönig, K; Müller, U; Münich, K; Nassiakou, M; Navarria, F; Nawrocki, K; Nicolaidou, R; Nikolenko, M; Oblakowska-Mucha, A; Obraztsov, V F; Olshevskii, A G; Onofre, A; Orava, R; Ouraou, A; Oyanguren, A; Paganoni, M; Paiano, S; Palacios, J P; Palka, H; Papadopoulou, T D; Pape, L; Parkes, C; Parodi, F; Parzefall, U; Passeri, A; Passon, O; Peralta, L; Perepelitsa, V F; Perrotta, A; Petrolini, A; Piedra, J; Pieri, L; Pierre, F; Pimenta, M; Piotto, E; Podobnik, T; Poireau, V; Pol, M E; Polok, G; Pozdnyakov, V; Pukhaeva, N; Pullia, A; Rames, J; Read, A; Rebecchi, P; Rehn, J; Reid, D; Reinhardt, R; Renton, P B; Richard, F; Rivero, M; Rodríguez, D; Romero, A; Ronchese, P; Roudeau, P; Rovelli, T; Ruhlmann-Kleider, V; Ryabtchikov, D; Rídky, J; Sadovskii, A; Salmi, L; Salt, J; Sander, C; Savoy-Navarro, A; Schwickerath, U; Sekulin, R L; Shlyapnikov, P; Siebel, M; Sisakian, A; Smadja, G; Smirnova, O; Sokolov, A; Sopczak, A; Sosnowski, R; Spassoff, Tz; Stanitzki, M; Stocchi, A; Strauss, J; Stugu, B; Szczekowski, M; Szeptycka, M; Szumlak, T; Tabarelli de Fatis, T; Taffard, A C; Tegenfeldt, F; Timmermans, J; Tkatchev, L G; Tobin, M; Todorovova, S; Tomé, B; Tonazzo, A; Tortosa, P; Travnicek, P; Treille, D; Tristram, G; Trochimczuk, M; Troncon, C; Turluer, M L; Tyapkin, I A; Tyapkin, P; Tzamarias, S; Uvarov, V; Valenti, G; Van Eldik, J; Van Remortel, N; Van Vulpen, I; Vegni, G; Veloso, F; Venus, W; Verdier, P; Verzi, V; Vilanova, D; Vitale, L; Vrba, V; Wahlen, H; Washbrook, A J; Weiser, C; Wicke, D; Wickens, J; Wilkinson, G; Winter, M; Witek, M; Yushchenko, O P; Zalewska-Bak, A; Zalewski, P; Zavrtanik, D; Zhuravlov, V; Zimin, N I; Zintchenko, A; Zupan, M; de Boer, Wim; van Dam, P; Åsman, B; Österberg, K

    2006-01-01

    The study of quark jets in e+e- reactions at LEP has demonstrated that the hadronisation process is reproduced well by the Lund string model. However, our understanding of gluon fragmentation is less complete. In this study enriched quark and gluon jet samples of different purities are selected in three-jet events from hadronic decays of the Z collected by the DELPHI experiment in the LEP runs during 1994 and 1995. The leading systems of the two kinds of jets are defined by requiring a rapidity gap and their sum of charges is studied. An excess of leading systems with total charge zero is found for gluon jets in all cases, when compared to Monte Carlo Simulations with JETSET (with and without Bose-Einstein correlations included) and ARIADNE. The corresponding leading systems of quark jets do not exhibit such an excess. The influence of the gap size and of the gluon purity on the effect is studied and a concentration of the excess of neutral leading systems at low invariant masses (<~ 2 GeV/c^2) is observed...

  9. histomorphormetric studies on lactational lead intoxication in testes ...

    African Journals Online (AJOL)

    2018-02-28

    Feb 28, 2018 ... The sedated animal was weighed on a weighing balance and figure recorded. The animal was then perfused to clear blood from the organs before the ... Odukoya AO. Histomorphormetric studies on lactational lead intoxication in testes of sprague dawley rats. Anatomy Journal of Africa. 7: 1141 – 1151.

  10. Micropipette Technique Study of Natural and Synthetic Lung Surfactants at the Air–Water Interface

    DEFF Research Database (Denmark)

    Ortiz, Elisa Parra; Kinoshita, K.; Needham, D.

    2016-01-01

    The present study is a microscopic interfacial characterization of a series of lung surfactant materials performed with the micropipette technique. The advantages of this technique include the measurement of equilibrium and dynamic surface tensions while acquiring structural and dynamic information...... at microscopic air-water interfaces in real time and upon compression. Here, we characterized a series of animal-derived and synthetic lung surfactant formulations, including native surfactant obtained from porcine lungs (NS); the commercial Curosurf, Infasurf, and Survanta; and a synthetic Super Mini-B (SMB...... but neither in the other clinical surfactants nor in protein-free preparations. Finally, the connection between this data and the observations from the lung surfactant literature concerning the widely reported "near-zero surface tension" for lung surfactant films and intact alveolar surfaces is also discussed...

  11. Custom-Made Synthetic Scaffolds for Bone Reconstruction: A Retrospective, Multicenter Clinical Study on 15 Patients

    Directory of Open Access Journals (Sweden)

    Fabrizia Luongo

    2016-01-01

    Full Text Available Purpose. To present a computer-assisted-design/computer-assisted-manufacturing (CAD/CAM technique for the design, fabrication, and clinical application of custom-made synthetic scaffolds, for alveolar ridge augmentation. Methods. The CAD/CAM procedure consisted of (1 virtual planning/design of the custom-made scaffold; (2 milling of the scaffold into the exact size/shape from a preformed synthetic bone block; (3 reconstructive surgery. The main clinical/radiographic outcomes were vertical/horizontal bone gain, any biological complication, and implant survival. Results. Fifteen patients were selected who had been treated with a custom-made synthetic scaffold for ridge augmentation. The scaffolds closely matched the shape of the defects: this reduced the operation time and contributed to good healing. A few patients experienced biological complications, such as pain/swelling (2/15: 13.3% and exposure of the scaffold (3/15: 20.0%; one of these had infection and complete graft loss. In all other patients, 8 months after reconstruction, a well-integrated newly formed bone was clinically available, and the radiographic evaluation revealed a mean vertical and horizontal bone gain of 2.1±0.9 mm and 3.0±1.0 mm, respectively. Fourteen implants were placed and restored with single crowns. The implant survival rate was 100%. Conclusions. Although positive outcomes have been found with custom-made synthetic scaffolds in alveolar ridge augmentation, further studies are needed to validate this technique.

  12. Synthetic Rock Analogue for Permeability Studies of Rock Salt with Mudstone

    Directory of Open Access Journals (Sweden)

    Hongwu Yin

    2017-09-01

    Full Text Available Knowledge about the permeability of surrounding rock (salt rock and mudstone interlayer is an important topic, which acts as a key parameter to characterize the tightness of gas storage. The goal of experiments that test the permeability of gas storage facilities in rock salt is to develop a synthetic analogue to use as a permeability model. To address the permeability of a mudstone/salt layered and mixed rock mass in Jintan, Jiangsu Province, synthetic mixed and layered specimens using the mudstone and the salt were fabricated for permeability testing. Because of the gas “slippage effect”, test results are corrected by the Klinkenberg method, and the permeability of specimens is obtained by regression fitting. The results show that the permeability of synthetic pure rock salt is 6.9 × 10−20 m2, and its porosity is 3.8%. The permeability of synthetic mudstone rock is 2.97 × 10−18 m2, with a porosity 17.8%. These results are close to those obtained from intact natural specimens. We also find that with the same mudstone content, the permeability of mixed specimens is about 40% higher than for the layered specimens, and with an increase in the mudstone content, the Klinkenberg permeability increases for both types of specimens. The permeability and mudstone content have a strong exponential relationship. When the mudstone content is below 40%, the permeability increases only slightly with mudstone content, whereas above this threshold, the permeability increases rapidly with mudstone content. The results of the study are of use in the assessment of the tightness of natural gas storage facilities in mudstone-rich rock salt formations in China.

  13. Comparative Study of Ashwagandha and Commercial Synthetic Compound on Performance of Broilers during Hot Weather

    Directory of Open Access Journals (Sweden)

    J. M. Shisodiya

    Full Text Available The trial was conducted for a period of six weeks on 225 day old broiler chicks, uniformly distributed into four groups of 75 chicks in each T1, T2 and T3 group. The chicks were fed with standard starter mash which contained crude protein 22.84% and metabolizable energy 2852.5 Kcal / kg (calculated value up to three weeks of age. For next 3 weeks i.e. from 4 to 6 weeks of age with finisher mash which contained crude protein 20% and metabolizable energy 2966 Kcal / kg (calculated value. Group T1 received standard broiler diet. Group T2 and T3 received standard broiler diet supplemented with Ashwagandha and commercial synthetic compound @ 0.05 % of feed respectively. The experimental birds were reared on deep litter system and rice husk was used as litter material.The supplementation of Aswagandha and commercial synthetic compound recorded significant improvement in all studied growth parameter i.e. live body weights, weekly gain in body weights and feed conversion ratio was observed in all the supplemented groups over the control group. However, feed consumption in control group was significantly higher than supplemented group. The economic returns of supplemented groups are more than the unsupplemented group. The net profit per bird was maximum in the commercial synthetic compound supplemented group followed by Ashwagandha supplemented group and lowest was recorded in control group (T1. [Veterinary World 2008; 1(10.000: 310-311

  14. Adherence to synthetic disease-modifying Antirheumatic Drugs in Rheumatoid Arthritis: Results of the OBSERVAR Study.

    Science.gov (United States)

    Juan Mas, Antonio; Castañeda, Santos; Cantero Santamaría, José I; Baquero, José L; Del Toro Santos, Francisco J

    2017-12-27

    Treatment compliance with disease-modifying antirheumatic drugs (DMARD) is essential to achieve the therapeutic goals in rheumatoid arthritis (RA). However, despite the need for good compliance, there is evidence that patients with RA frequently fail to use DMARD for the control of RA. Thus, the main objective of the OBSERVAR study is to evaluate the reasons for the lack of therapeutic adherence to synthetic DMARD in these patients. A Delphi process involving 18 randomly selected Spanish rheumatologists determined the level of agreement with 66 causes of noncompliance selected from the literature in relation to synthetic DMARD in RA. The reasons for noncompliance were consistent in 75.7%, although 3 reasons (4.5%) were highly consistent: 1) not knowing what to do in the case of an adverse event with DMARD; 2) not having undergone adherence screening by health personnel for early detection of "noncompliant patients"; and 3) not having undergone interventions or strategies that improve adherence. In order to improve adherence to RA treatment with synthetic DMARD, the patient should be adequately informed of each new treatment introduced, the patient's compliance profile should be incorporated into the clinical routine and the patient's motivation for therapeutic compliance be reinforced through the methods available to us. Copyright © 2017 Elsevier España, S.L.U. and Sociedad Española de Reumatología y Colegio Mexicano de Reumatología. All rights reserved.

  15. Lead isotope ratios as a tracer for lead contamination sources: A lake Andong case study

    Directory of Open Access Journals (Sweden)

    Kim Y. H

    2013-04-01

    Full Text Available The objective of this study was to evaluate stable Pb isotope signatures as a tracer for Pb contamination in Lake Andong. For Pb isotope analysis, we collected water and sediment from Lake Andong, particles in the air, soils, and stream water, mine tailings, sludge and wastewater from zinc smelting around lake Andong watershed. The results showed that Pb isotope ratios (206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb for zinc concentrate were 18.809 ± 0.322, 15.650 ± 0.062, and 38.728 ± 0.421, respectively. In wastewater, isotopic ratio values (206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb were 17.363 ± 0.133, 15.550 ± 0.025, and 37.217 ± 0.092, respectively. Additionally, isotopic ratio values (206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb for sludge were 17.515 ± 0.155, 15.537 ± 0.018, and 37.357 ± 0.173, respectively. These values were similar to those in zinc and lead concentrate originated from Canada and South America. In contrast, Pb isotope ratios of soil, tailings and sediment from Lake Andong were similar to those of Korean ore. Atmospheric particles showed different patterns of Pb isotope ratios from sediments, soils, and zinc smelting and this needs further investigation in order to identify atmospheric Pb sources.

  16. Synthetic hematocrit derived from the longitudinal relaxation of blood can lead to clinically significant errors in measurement of extracellular volume fraction in pediatric and young adult patients.

    Science.gov (United States)

    Raucci, Frank J; Parra, David A; Christensen, Jason T; Hernandez, Lazaro E; Markham, Larry W; Xu, Meng; Slaughter, James C; Soslow, Jonathan H

    2017-08-02

    Extracellular volume fraction (ECV) is altered in pathological cardiac remodeling and predicts death and arrhythmia. ECV can be quantified using cardiovascular magnetic resonance (CMR) T1 mapping but calculation requires a measured hematocrit (Hct). The longitudinal relaxation of blood has been used in adults to generate a synthetic Hct (estimate of true Hct) but has not been validated in pediatric populations. One hundred fourteen children and young adults underwent a total of 163 CMRs with T1 mapping. The majority of subjects had a measured Hct the same day (N = 146). Native and post-contrast T1 were determined in blood pool, septum, and free wall of mid-LV, avoiding areas of late gadolinium enhancement. Synthetic Hct and ECV were calculated and intraclass correlation coefficient (ICC) and linear regression were used to compare measured and synthetic values. The mean age was 16.4 ± 6.4 years and mean left ventricular ejection fraction was 59% ± 9%. The mean measured Hct was 41.8 ± 3.0% compared to the mean synthetic Hct of 43.2% ± 2.9% (p measured mid-free wall ECV was 30.5% ± 4.8% and mean synthetic mid-free wall ECV of local model was 29.7% ± 4.6% (p measured and synthetic ECV ranged from -8.4% to 4.3% in the septum and -12.6% to 15.8% in the free wall. Using our laboratory's normal cut-off of 28.5%, 59 patients (37%) were miscategorized (53 false negatives, 6 false positives) with published model ECV. The local model had 37 miscategorizations (20 false negatives, 17 false positives), significantly fewer but still a substantial number (23%). Our data suggest that use of synthetic Hct for the calculation of ECV results in miscategorization of individual patients. This difference may be less significant once synthetic ECV is calculated and averaged over a large research cohort, making it potentially useful as a research tool. However, we recommend formal measurement of Hct in children and young adults for clinical CMRs.

  17. Lead (Pb) isotopic fingerprinting and its applications in lead pollution studies in China: A review

    International Nuclear Information System (INIS)

    Cheng Hefa; Hu Yuanan

    2010-01-01

    As the most widely scattered toxic metal in the world, the sources of lead (Pb) observed in contamination investigation are often difficult to identify. This review presents an overview of the principles, analysis, and applications of Pb isotopic fingerprinting in tracing the origins and transport pathways of Pb in the environment. It also summarizes the history and current status of lead pollution in China, and illustrates the power of Pb isotopic fingerprinting with examples of its recent applications in investigating the effectiveness of leaded gasoline phase-out on atmospheric lead pollution, and the sources of Pb found in various environmental media (plants, sediments, and aquatic organisms) in China. The limitations of Pb isotopic fingerprinting technique are discussed and a perspective on its development is also presented. Further methodological developments and more widespread instrument availability are expected to make isotopic fingerprinting one of the key tools in lead pollution investigation. - This review presents an overview of the principles, applications, and limitations of Pb isotopic fingerprinting in lead pollution investigation, and provides a perspective on its future development.

  18. Lead (Pb) isotopic fingerprinting and its applications in lead pollution studies in China: A review

    Energy Technology Data Exchange (ETDEWEB)

    Cheng Hefa, E-mail: hefac@umich.ed [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Hu Yuanan [Education Program for Gifted Youth, Stanford University, Stanford, CA 94025 (United States)

    2010-05-15

    As the most widely scattered toxic metal in the world, the sources of lead (Pb) observed in contamination investigation are often difficult to identify. This review presents an overview of the principles, analysis, and applications of Pb isotopic fingerprinting in tracing the origins and transport pathways of Pb in the environment. It also summarizes the history and current status of lead pollution in China, and illustrates the power of Pb isotopic fingerprinting with examples of its recent applications in investigating the effectiveness of leaded gasoline phase-out on atmospheric lead pollution, and the sources of Pb found in various environmental media (plants, sediments, and aquatic organisms) in China. The limitations of Pb isotopic fingerprinting technique are discussed and a perspective on its development is also presented. Further methodological developments and more widespread instrument availability are expected to make isotopic fingerprinting one of the key tools in lead pollution investigation. - This review presents an overview of the principles, applications, and limitations of Pb isotopic fingerprinting in lead pollution investigation, and provides a perspective on its future development.

  19. Study of the discharge characteristics of lead-acid batteries

    Energy Technology Data Exchange (ETDEWEB)

    Horvath, P.; Jedlovszky, P.; Benedek, M.

    1982-07-01

    A theoretical analysis of the electrolyte concentration distribution and current distribution in the porous lead dioxide electrode has been made by application of Fick's second law which was combined with approximate mass balances. The macrohomogeneous model for porous electrodes was used. The parameters in the models were determined experimentally for the lead dioxide battery plates and the special experimental cylindrical electrodes investigated. Numerical solutions for special cases are discussed. Theoretical results are in good agreement with experimental determinations. According to laser interferometry analysis the assumption of convectionless diffusion is, in practice, a good approximation in most cases. Theoretical studies of the local overpotential show that the utilizable capacity is determined by the decreasing ionic concentration of the electrolyte because the electrode reaction takes place mainly in the outer layers of the electrode, if the discharge current has a high value, e.g. full discharge times is less than 10 min.

  20. ESR studies of high-energy phosphorus-ion implanted synthetic diamond crystals

    Energy Technology Data Exchange (ETDEWEB)

    Isoya, J. [University of Library and Information Science, Tsukuba, Ibaraki (Japan); Kanda, H.; Morita, Y.; Ohshima, T.

    1997-03-01

    Phosphorus is among potential n-type dopants in diamond. High pressure synthetic diamond crystals of type IIa implanted with high energy (9-18 MeV) phosphorus ions have been studied by using electron spin resonance (ESR) technique. The intensity and the linewidth of the ESR signal attributed to the dangling bond of the amorphous phase varied with the implantation dose, suggesting the nature of the amorphization varies with the dose. The ESR signals of point defects have been observed in the low dose as-implanted crystals and in the high dose crystals annealed at high temperature and at high pressure. (author)

  1. Bacteriophage-based synthetic biology for the study of infectious diseases

    Science.gov (United States)

    Lu, Timothy K.

    2014-01-01

    Since their discovery, bacteriophages have contributed enormously to our understanding of molecular biology as model systems. Furthermore, bacteriophages have provided many tools that have advanced the fields of genetic engineering and synthetic biology. Here, we discuss bacteriophage-based technologies and their application to the study of infectious diseases. New strategies for engineering genomes have the potential to accelerate the design of novel phages as therapies, diagnostics, and tools. Though almost a century has elapsed since their discovery, bacteriophages continue to have a major impact on modern biological sciences, especially with the growth of multidrug-resistant bacteria and interest in the microbiome. PMID:24997401

  2. Selectivity in ligand binding to uranyl compounds: A synthetic, structural, thermodynamic and computational study

    International Nuclear Information System (INIS)

    Arnold, John

    2015-01-01

    The uranyl cation (UO 2 2+ ) is the most abundant form of uranium on the planet. It is estimated that 4.5 billion tons of uranium in this form exist in sea water. The ability to bind and extract the uranyl cation from aqueous solution while separating it from other elements would provide a limitless source of nuclear fuel. A large body of research concerns the selective recognition and extraction of uranyl. A stable molecule, the cation has a linear O=U=O geometry. The short U-O bonds (1.78 Å) arise from the combination of uranium 5f/6d and oxygen 2p orbitals. Due to the oxygen moieties being multiply bonded, these sites were not thought to be basic enough for Lewis acidic coordination to be a viable approach to sequestration. The goal of this research is thus to broaden the coordination chemistry of the uranyl ion by studying new ligand systems via synthetic, structural, thermodynamic and computational methods. It is anticipated that this fundamental science will find use beyond actinide separation technologies in areas such as nuclear waste remediation and nuclear materials. The focus of this study is to synthesize uranyl complexes incorporating amidinate and guanidinate ligands. Both synthetic and computational methods are used to investigate novel equatorial ligand coordination and how this affects the basicity of the oxo ligands. Such an understanding will later apply to designing ligands incorporating functionalities that can bind uranyl both equatorially and axially for highly selective sequestration. Efficient and durable chromatography supports for lanthanide separation will be generated by (1) identifying robust peptoid-based ligands capable of binding different lanthanides with variable affinities, and (2) developing practical synthetic methods for the attachment of these ligands to Dowex ion exchange resins.

  3. Selectivity in ligand binding to uranyl compounds: A synthetic, structural, thermodynamic and computational study

    Energy Technology Data Exchange (ETDEWEB)

    Arnold, John [Univ. of California, Berkeley, CA (United States)

    2015-01-21

    The uranyl cation (UO₂²⁺) is the most abundant form of uranium on the planet. It is estimated that 4.5 billion tons of uranium in this form exist in sea water. The ability to bind and extract the uranyl cation from aqueous solution while separating it from other elements would provide a limitless source of nuclear fuel. A large body of research concerns the selective recognition and extraction of uranyl. A stable molecule, the cation has a linear O=U=O geometry. The short U-O bonds (1.78 Å) arise from the combination of uranium 5f/6d and oxygen 2p orbitals. Due to the oxygen moieties being multiply bonded, these sites were not thought to be basic enough for Lewis acidic coordination to be a viable approach to sequestration. The goal of this research is thus to broaden the coordination chemistry of the uranyl ion by studying new ligand systems via synthetic, structural, thermodynamic and computational methods. It is anticipated that this fundamental science will find use beyond actinide separation technologies in areas such as nuclear waste remediation and nuclear materials. The focus of this study is to synthesize uranyl complexes incorporating amidinate and guanidinate ligands. Both synthetic and computational methods are used to investigate novel equatorial ligand coordination and how this affects the basicity of the oxo ligands. Such an understanding will later apply to designing ligands incorporating functionalities that can bind uranyl both equatorially and axially for highly selective sequestration. Efficient and durable chromatography supports for lanthanide separation will be generated by (1) identifying robust peptoid-based ligands capable of binding different lanthanides with variable affinities, and (2) developing practical synthetic methods for the attachment of these ligands to Dowex ion exchange resins.

  4. Evaluation of synthetic hydrocarbons for mark-recapture studies on the red milkweed beetle.

    Science.gov (United States)

    Ginzel, Matthew D; Hanks, Lawrence M

    2002-05-01

    This study evaluates the potential for using blends of synthetic hydrocarbons in mark-recapture studies of insects. To test the durability of hydrocarbons, we applied a blend of five straight-chain hydrocarbons (C24, C21, C26. C28, C30) to detached elytra of the red milkweed beetle, Tetraopes tetrophthalmus (Forster) (Coleoptera: Cerambycidae), mounted the elytra on pins, and placed them in an exposed location outdoors. The amount of hydrocarbons on the elytra did not change over time, even after two months of exposure to sun and rain. Synthetic hydrocarbons applied to the elytra of living beetles did not significantly influence their longevity or mating success in a laboratory study. and the amounts of hydrocarbons did not change with age. The invariability of hydrocarbon ratios over time suggests that blends could provide a nearly infinite variety of ratios to mark individual insects uniquely and indelibly with a hydrocarbon "fingerprint." This technique offers a convenient, safe, and durable means of individually marking insects and may find application in field studies of larger bodied insects that are long-lived and sedentary.

  5. In-situ study of ferric iron distribution in synthetic spinels by electron microprobe analysis

    Science.gov (United States)

    Goncharov, Alexey; Olga, Sinelshikova; Rustam, Lukmanov

    2017-04-01

    The iron oxidation state in mantle minerals is a key value in oxygen fugacity calculation and the most widely used analytical approach for Fe3+/ΣFe determination is Mössbauer spectroscopy, which is a bulk method and there is a lack of information on Fe3+/ΣFe zonation in individual mineral grains and Fe3+/ΣFe in inclusions. Here we present application of the flank method using the electron microprobe by analysing the FeLα and FeLβ X-ray emission spectra to a suite of 20 synthetic MgAl2O2-Cr2O3-Fe2O3(FeO) spinels. Materials were done with 5 - 25 FeO wt.%, and 2-70 Cr2O3 wt.% and Fe3+/ΣFe = 0.10 to 0.80, where Fe3+/ΣFe was determined independently using Mössbauer spectroscopy on the same grains used for the flank method measurements. Synthesis of the samples produced using a pyrolysis method of organic salt compositions in MgAl2O2-Cr2O3-Fe2O3(FeO) system with following heating in corundum crucibles at 1300 ° C for 5 -10 hours under controlled oxygen fugacity. All synthetic materials were investigated by X-ray and Mössbauer spectroscopy to examine a phase and iron oxidation state features. In terms of chemical composition and Fe3+/ΣFe resulting synthetic material covers a whole range of spinels derived in mantle peridotites and pyroxenites. These synthetic products were used as a standard sample to investigate co-variations of ratios of intensities measured on the flanks of FeLα and Lβ peaks and Fe3+/ΣFe, FeO content and Cr#. The obtained correlations can be used to perform in-situ studies of ferric iron distribution in natural mantle spinels. The presented approach will allow investigating the difference in mantle spinel Fe3+/ΣFe at a microscale from core to rim in individual grain, inclusion, melting pocket and in intergrows with other mantle mineral assemblage. The reported study was funded by RFBR according to the research project № 16-35-60076 mol_a_dk.

  6. A randomised cross-over pharmacokinetic bioavailability study of synthetic versus kiwifruit-derived vitamin C.

    Science.gov (United States)

    Carr, Anitra C; Bozonet, Stephanie M; Vissers, Margreet C M

    2013-11-11

    Kiwifruit are a rich source of vitamin C and also contain numerous phytochemicals, such as flavonoids, which may influence the bioavailability of kiwifruit-derived vitamin C. The aim of this study was to compare the relative bioavailability of synthetic versus kiwifruit-derived vitamin C using a randomised cross-over pharmacokinetic study design. Nine non-smoking males (aged 18-35 years) received either a chewable tablet (200 mg vitamin C) or the equivalent dose from gold kiwifruit (Actinidia chinensis var. Sungold). Fasting blood and urine were collected half hourly to hourly over the eight hours following intervention. The ascorbate content of the plasma and urine was determined using HPLC with electrochemical detection. Plasma ascorbate levels increased from 0.5 h after the intervention (P = 0.008). No significant differences in the plasma time-concentration curves were observed between the two interventions (P = 0.645). An estimate of the total increase in plasma ascorbate indicated complete uptake of the ingested vitamin C tablet and kiwifruit-derived vitamin C. There was an increase in urinary ascorbate excretion, relative to urinary creatinine, from two hours post intervention (P vitamin C tablet and kiwifruit arms, respectively. Overall, our pharmacokinetic study has shown comparable relative bioavailability of kiwifruit-derived vitamin C and synthetic vitamin C.

  7. A scenario study of seismically induced landsliding in Seattle using broadband synthetic seismograms

    Science.gov (United States)

    Allstadt, Kate E.; Vidale, John E.; Frankel, Arthur D.

    2013-01-01

    We demonstrate the value of utilizing broadband synthetic seismograms to assess regional seismically induced landslide hazard. Focusing on a case study of an Mw 7.0 Seattle fault earthquake in Seattle, Washington, we computed broadband synthetic seismograms that account for rupture directivity and 3D basin amplification. We then adjusted the computed motions on a fine grid for 1D amplifications based on the site response of typical geologic profiles in Seattle and used these time‐series ground motions to trigger shallow landsliding using the Newmark method. The inclusion of these effects was critical in determining the extent of landsliding triggered. We found that for inertially triggered slope failures modeled by the Newmark method, the ground motions used to simulate landsliding must have broadband frequency content in order to capture the full slope displacement. We applied commonly used simpler methods based on ground‐motion prediction equations for the same scenario and found that they predicted far fewer landslides if only the mean values were used, but far more at the maximum range of the uncertainties, highlighting the danger of using just the mean values for such methods. Our results indicate that landsliding triggered by a large Seattle fault earthquake will be extensive and potentially devastating, causing direct losses and impeding recovery. The high impact of landsliding predicted by this simulation shows that this secondary effect of earthquakes should be studied with as much vigor as other earthquake effects.

  8. Geometric Studies of Shunt and Lead Orientation in EEC Devices

    Science.gov (United States)

    Werner, F. M.; Solin, S. A.

    2014-03-01

    Electric field sensors are ubiquitous in modern technology, from field effect transistors (FETs) in circuit boards to point-of-care testing (POCT) devices used in detecting the presence of specific protein markers in blood. The transport properties of these devices are limited by two general categories: intrinsic material properties and extrinsic geometric effects. Devices with a maximum electric field resolution of 3.05V/cm were previously reported. The metal semiconductor hybrid (MSH) devices are constructed by forming a Schottky interface between a mesa of nGaAs and Ti, while four ohmic leads surround the perimeter of the mesa and are used for four point resistance measurements. These devices exhibit extraordinary electroconductance (EEC) and make it possible to correlate measured four point resistance to changes in the local electric field. While maximizing the EEC response by optimizing the intrinsic material properties has been theoretically investigated, we present a phenomenological study of the impact of lead orientation and shunt geometry in the sensing capabilities of these devices. S.A.S. is a co-founder of and has a financial interest in PixelEXX, a start-up company whose mission is to market imaging arrays.

  9. Synthetic hydrogeological study on Beishan preselected area for high-level radioactive waste repository in China

    International Nuclear Information System (INIS)

    Guo Yonghai; Su Rui; Ji Ruili; Wang Hailong; Liu Shufen; Zong Zihua; Dong Jiannan; Zhang Ming

    2014-01-01

    On the basis of large scale field hydrogeological investigation, synthetic hydrogeological studies related to groundwater system characteristics, permeability of rock bodies, groundwater dynamic, hydrogeochemistry, isotopic hydrology, CFC's of groundwater and groundwater flow field simulation were carried out for Beishan area, Gansu province. According to analysis on a large amount of hydrogeological data, the characteristics of groundwater circulation, groundwater hydrodynamics and hydrgeochemistry were described and the suitability of Beishan area as the potential area of high-level radioactive waste disposal was evaluated in the paper. Through this study, the hydrogeological study and evaluation methods in the siting of China's high level radioactive waste repository were set up. Furthermore, the important hydrogeological scientific evidence was provided for optimal site filtration of China's high-level radioactive waste repository in Beishan area. (authors)

  10. Lead-Related Genetic Loci, Cumulative Lead Exposure and Incident Coronary Heart Disease: The Normative Aging Study.

    Science.gov (United States)

    Ding, Ning; Wang, Xin; Weisskopf, Marc G; Sparrow, David; Schwartz, Joel; Hu, Howard; Park, Sung Kyun

    2016-01-01

    Cumulative exposure to lead is associated with cardiovascular outcomes. Polymorphisms in the δ-aminolevulinic acid dehydratase (ALAD), hemochromatosis (HFE), heme oxygenase-1 (HMOX1), vitamin D receptor (VDR), glutathione S-transferase (GST) supergene family (GSTP1, GSTT1, GSTM1), apolipoprotein E (APOE),angiotensin II receptor-1 (AGTR1) and angiotensinogen (AGT) genes, are believed to alter toxicokinetics and/or toxicodynamics of lead. We assessed possible effect modification by genetic polymorphisms in ALAD, HFE, HMOX1, VDR, GSTP1, GSTT1, GSTM1, APOE, AGTR1 and AGT individually and as the genetic risk score (GRS) on the association between cumulative lead exposure and incident coronary heart disease (CHD) events. We used K-shell-X-ray fluorescence to measure bone lead levels. GRS was calculated on the basis of 22 lead-related loci. We constructed Cox proportional hazard models to compute adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for incident CHD. We applied inverse probability weighting to account for potential selection bias due to recruitment into the bone lead sub-study. Significant effect modification was found by VDR, HMOX1, GSTP1, APOE, and AGT genetic polymorphisms when evaluated individually. Further, the bone lead-CHD associations became larger as GRS increases. After adjusting for potential confounders, a HR of CHD was 2.27 (95%CI: 1.50-3.42) with 2-fold increase in patella lead levels, among participants in the top tertile of GRS. We also detected an increasing trend in HRs across tertiles of GRS (p-trend = 0.0063). Our findings suggest that lead-related loci as a whole may play an important role in susceptibility to lead-related CHD risk. These findings need to be validated in a separate cohort containing bone lead, lead-related genetic loci and incident CHD data.

  11. Lead-Related Genetic Loci, Cumulative Lead Exposure and Incident Coronary Heart Disease: The Normative Aging Study.

    Directory of Open Access Journals (Sweden)

    Ning Ding

    Full Text Available Cumulative exposure to lead is associated with cardiovascular outcomes. Polymorphisms in the δ-aminolevulinic acid dehydratase (ALAD, hemochromatosis (HFE, heme oxygenase-1 (HMOX1, vitamin D receptor (VDR, glutathione S-transferase (GST supergene family (GSTP1, GSTT1, GSTM1, apolipoprotein E (APOE,angiotensin II receptor-1 (AGTR1 and angiotensinogen (AGT genes, are believed to alter toxicokinetics and/or toxicodynamics of lead.We assessed possible effect modification by genetic polymorphisms in ALAD, HFE, HMOX1, VDR, GSTP1, GSTT1, GSTM1, APOE, AGTR1 and AGT individually and as the genetic risk score (GRS on the association between cumulative lead exposure and incident coronary heart disease (CHD events.We used K-shell-X-ray fluorescence to measure bone lead levels. GRS was calculated on the basis of 22 lead-related loci. We constructed Cox proportional hazard models to compute adjusted hazard ratios (HRs and 95% confidence intervals (CIs for incident CHD. We applied inverse probability weighting to account for potential selection bias due to recruitment into the bone lead sub-study.Significant effect modification was found by VDR, HMOX1, GSTP1, APOE, and AGT genetic polymorphisms when evaluated individually. Further, the bone lead-CHD associations became larger as GRS increases. After adjusting for potential confounders, a HR of CHD was 2.27 (95%CI: 1.50-3.42 with 2-fold increase in patella lead levels, among participants in the top tertile of GRS. We also detected an increasing trend in HRs across tertiles of GRS (p-trend = 0.0063.Our findings suggest that lead-related loci as a whole may play an important role in susceptibility to lead-related CHD risk. These findings need to be validated in a separate cohort containing bone lead, lead-related genetic loci and incident CHD data.

  12. Lead-Related Genetic Loci, Cumulative Lead Exposure and Incident Coronary Heart Disease: The Normative Aging Study

    Science.gov (United States)

    Weisskopf, Marc G.; Sparrow, David; Schwartz, Joel; Hu, Howard; Park, Sung Kyun

    2016-01-01

    Background Cumulative exposure to lead is associated with cardiovascular outcomes. Polymorphisms in the δ-aminolevulinic acid dehydratase (ALAD), hemochromatosis (HFE), heme oxygenase-1 (HMOX1), vitamin D receptor (VDR), glutathione S-transferase (GST) supergene family (GSTP1, GSTT1, GSTM1), apolipoprotein E (APOE),angiotensin II receptor-1 (AGTR1) and angiotensinogen (AGT) genes, are believed to alter toxicokinetics and/or toxicodynamics of lead. Objectives We assessed possible effect modification by genetic polymorphisms in ALAD, HFE, HMOX1, VDR, GSTP1, GSTT1, GSTM1, APOE, AGTR1 and AGT individually and as the genetic risk score (GRS) on the association between cumulative lead exposure and incident coronary heart disease (CHD) events. Methods We used K-shell-X-ray fluorescence to measure bone lead levels. GRS was calculated on the basis of 22 lead-related loci. We constructed Cox proportional hazard models to compute adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for incident CHD. We applied inverse probability weighting to account for potential selection bias due to recruitment into the bone lead sub-study. Results Significant effect modification was found by VDR, HMOX1, GSTP1, APOE, and AGT genetic polymorphisms when evaluated individually. Further, the bone lead-CHD associations became larger as GRS increases. After adjusting for potential confounders, a HR of CHD was 2.27 (95%CI: 1.50–3.42) with 2-fold increase in patella lead levels, among participants in the top tertile of GRS. We also detected an increasing trend in HRs across tertiles of GRS (p-trend = 0.0063). Conclusions Our findings suggest that lead-related loci as a whole may play an important role in susceptibility to lead-related CHD risk. These findings need to be validated in a separate cohort containing bone lead, lead-related genetic loci and incident CHD data. PMID:27584680

  13. Electrochemical Studies of Lead Telluride Behavior in Acidic Nitrate Solutions

    Directory of Open Access Journals (Sweden)

    Rudnik E.

    2015-04-01

    Full Text Available Electrochemistry of lead telluride stationary electrode was studied in nitric acid solutions of pH 1.5-3.0. E-pH diagram for Pb-Te-H2O system was calculated. Results of cyclic voltammetry of Pb, Te and PbTe were discussed in correlation with thermodynamic predictions. Anodic dissolution of PbTe electrode at potential approx. -100÷50 mV (SCE resulted in tellurium formation, while above 300 mV TeO2 was mainly produced. The latter could dissolve to HTeO+2 under acidic electrolyte, but it was inhibited by increased pH of the bath.

  14. Synthetic Cannabinoids.

    Science.gov (United States)

    Mills, Brooke; Yepes, Andres; Nugent, Kenneth

    2015-07-01

    Synthetic cannabinoids (SCBs), also known under the brand names of "Spice," "K2," "herbal incense," "Cloud 9," "Mojo" and many others, are becoming a large public health concern due not only to their increasing use but also to their unpredictable toxicity and abuse potential. There are many types of SCBs, each having a unique binding affinity for cannabinoid receptors. Although both Δ-tetrahydrocannabinol (THC) and SCBs stimulate the same receptors, cannabinoid receptor 1 (CB1) and cannabinoid receptor 2 (CB2), studies have shown that SCBs are associated with higher rates of toxicity and hospital admissions than is natural cannabis. This is likely due to SCBs being direct agonists of the cannabinoid receptors, whereas THC is a partial agonist. Furthermore, the different chemical structures of SCBs found in Spice or K2 may interact in unpredictable ways to elicit previously unknown, and the commercial products may have unknown contaminants. The largest group of users is men in their 20s who participate in polydrug use. The most common reported toxicities with SCB use based on studies using Texas Poison Control records are tachycardia, agitation and irritability, drowsiness, hallucinations, delusions, hypertension, nausea, confusion, dizziness, vertigo and chest pain. Acute kidney injury has also been strongly associated with SCB use. Treatment mostly involves symptom management and supportive care. More research is needed to identify which contaminants are typically found in synthetic marijuana and to understand the interactions between different SBCs to better predict adverse health outcomes.

  15. A study on expelling lead with a traditional Chinese medicine

    International Nuclear Information System (INIS)

    Sun Aizhen; Guo Ruixin; Zhou Jieyan; Wang Dongfeng; Wang Huifang

    1993-01-01

    The rat model poisoned by lead acetate was treated with either EDTA or a traditional Chinese medicine (TCM) with the ability of 'relieving toxin and strengthening spleen'. In EDTA group, lead contents in blood fell to normal; the other parameters apparently improved but did not return to normal(p 0.05). But in TCM group, all the parameters returned to normal (p > 0.05) and the contents of essential trace elements in urine did not obviously change (p < 0.05). The curative effect of TCM is therefore better than that of EDTA. The mechanism probably lies in following points: (1) TCM can expedite excretion of lead in feces and decrease the lead accumulation in liver; (2) FEP returns to normal, showing that the lead expelling effect of TCM is relatively complete; (3) TCM does not disturb the interior equilibrium of essential trace elements while expelling lead

  16. Modeling induced polarization effects in helicopter time domain electromagnetic data: Synthetic case studies

    DEFF Research Database (Denmark)

    Viezzoli, Andrea; Kaminskiy, Vladislav; Fiandaca, Gianluca

    2017-01-01

    We have developed a synthetic multiparametric modeling and inversion exercise undertaken to study the robustness of inverting airborne time-domain electromagnetic (TDEM) data to extract Cole-Cole parameters. The following issues were addressed: nonuniqueness, ill posedness, dependency on manual...... constrained multiparametric inversion was evaluated, including recovery of chargeability distributions from shallow and deep targets based on analysis of induced polarization (IP) effects, simulated in airborne TDEM data. Different scenarios were studied, including chargeable targets associated...... by a shallower chargeable target, became possible only when full Cole-Cole modeling was used in the inversion. Lateral constraints improved the recoverability of model parameters. Finally, modeling IP effects increased the accuracy of recovered electrical resistivity models....

  17. A Comparative Study of Defibrillator Leads at a Large-Volume Implanting Hospital: Results From the Pacemaker and Implantable Defibrillator Leads Survival Study ("PAIDLESS").

    Science.gov (United States)

    Cohen, Todd J; Asheld, Wilbur J; Germano, Joseph; Islam, Shahidul; Patel, Dhimesh

    2015-06-01

    The purpose of the study was to examine survival in the implantable defibrillator subset of implanted leads at a large-volume implanting hospital. Implantable lead survival has been the subject of many multicenter studies over the past decade. Fewer large implanting volume single-hospital studies have examined defibrillator lead failure as it relates to patient survival and lead construction. This investigator-initiated retrospective study examined defibrillator lead failure in those who underwent implantation of a defibrillator between February 1, 1996 and December 31, 2011. Lead failure was defined as: failure to capture/sense, abnormal pacing and/or defibrillator impedance, visual insulation defect or lead fracture, extracardiac stimulation, cardiac perforation, tricuspid valve entrapment, lead tip fracture and/or lead dislodgment. Patient characteristics, implant approach, lead manufacturers, lead models, recalled status, patient mortality, and core lead design elements were compared using methods that include Kaplan Meier analysis, univariate and multivariable Cox regression models. A total of 4078 defibrillator leads were implanted in 3802 patients (74% male; n = 2812) with a mean age of 70 ± 13 years at Winthrop University Hospital. Lead manufacturers included: Medtronic: [n = 1834; 801 recalled]; St. Jude Medical: [n = 1707; 703 recalled]; Boston Scientific: [n = 537; 0 recalled]. Kaplan-Meier analysis adjusted for multiple comparisons revealed that both Boston Scientific's and St. Jude Medical's leads had better survival than Medtronic's leads (Pdefibrillation coil, and recalled lead status all contributed to lead failure. This study demonstrated a significantly improved lead performance in the Boston Scientific and St. Jude leads as compared with Medtronic leads. Some lead construction variables (insulation and number of coils) also had a significant impact on lead failure, which was independent of the manufacturer. Recalled St. Jude leads performed

  18. Study of the Biological Activity of Novel Synthetic Compounds with Antiviral Properties against Human Rhinoviruses

    Directory of Open Access Journals (Sweden)

    Raffaello Pompei

    2011-04-01

    Full Text Available Picornaviridae represent a very large family of small RNA viruses, some of which are the cause of important human and animal diseases. Since no specific therapy against any of these viruses currently exists, palliative symptomatic treatments are employed. The early steps of the picornavirus replicative cycle seem to be privileged targets for some antiviral compounds like disoxaril and pirodavir. Pirodavir’s main weakness is its cytotoxicity on cell cultures at relatively low doses. In this work some original synthetic compounds were tested, in order to find less toxic compounds with an improved protection index (PI on infected cells. Using an amino group to substitute the oxygen atom in the central chain, such as that in the control molecule pirodavir, resulted in decreased activity against Rhinoviruses and Polioviruses. The presence of an -ethoxy-propoxy- group in the central chain (as in compound I-6602 resulted in decreased cell toxicity and in improved anti-Rhinovirus activity. This compound actually showed a PI >700 on HRV14, while pirodavir had a PI of 250. These results demonstrate that modification of pirodavir’s central hydrocarbon chain can lead to the production of novel derivatives with low cytotoxicity and improved PI against some strains of Rhinoviruses.

  19. Study of the biological activity of novel synthetic compounds with antiviral properties against human rhinoviruses.

    Science.gov (United States)

    Laconi, Samuela; Madeddu, Maria A; Pompei, Raffaello

    2011-04-26

    Picornaviridae represent a very large family of small RNA viruses, some of which are the cause of important human and animal diseases. Since no specific therapy against any of these viruses currently exists, palliative symptomatic treatments are employed. The early steps of the picornavirus replicative cycle seem to be privileged targets for some antiviral compounds like disoxaril and pirodavir. Pirodavir's main weakness is its cytotoxicity on cell cultures at relatively low doses. In this work some original synthetic compounds were tested, in order to find less toxic compounds with an improved protection index (PI) on infected cells. Using an amino group to substitute the oxygen atom in the central chain, such as that in the control molecule pirodavir, resulted in decreased activity against Rhinoviruses and Polioviruses. The presence of an -ethoxy-propoxy- group in the central chain (as in compound I-6602) resulted in decreased cell toxicity and in improved anti-Rhinovirus activity. This compound actually showed a PI >700 on HRV14, while pirodavir had a PI of 250. These results demonstrate that modification of pirodavir's central hydrocarbon chain can lead to the production of novel derivatives with low cytotoxicity and improved PI against some strains of Rhinoviruses.

  20. A chemometric study of ageing in lead-based paints.

    Science.gov (United States)

    Pallipurath, Anuradha; Skelton, Jonathan; Bucklow, Spike; Elliott, Stephen

    2015-11-01

    The development of non-invasive analytical methods is of widespread interest to the field of conservation science, providing chemical insight into the materials used to create painted works of art, which can, for example, inform decisions about their restoration and preservation, or help discern original works from forgeries. A key undertaking in this area is to develop practical methods for identifying and understanding the chemical processes that occur in paint films under ageing. Furthermore, whereas a number of scientific studies have focussed on model systems in which natural ageing processes are simulated in a short time by irradiation under ultraviolet (UV) light, it remains to be established to what extent natural and accelerated ageing induce similar chemical changes. In this work, we employ FT-Raman spectroscopy, together with a simple spectral-deconvolution algorithm, to study in detail the spectral changes accompanying the natural and UV-accelerated ageing of lead-based paint films. We find that the two processes differ significantly, and that spectroscopic signatures, principally in the fluorescence background, can thus be used to differentiate the two modes of ageing and hence possibly to identify attempted forgeries. Our studies also suggest that paints based on proteinaceous binders are more stable to ageing than lipid-bound ones. Finally, we investigate the possibility of using our chemometric deconvolution technique, in conjunction with multivariate analysis, for the semi-automated characterisation of the degree or extent of ageing in unknown samples. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. An exploratory study of lead recovery in lead-acid battery lifecycle in US market: An evidence-based approach

    International Nuclear Information System (INIS)

    Genaidy, A.M.; Sequeira, R.; Tolaymat, T.; Kohler, J.; Rinder, M.

    2008-01-01

    Background: This research examines lead recovery and recycling in lead-acid batteries (LAB) which account for 88% of US lead consumption. We explore strategies to maximize lead recovery and recycling in the LAB lifecycle. Currently, there is limited information on recycling rates for LAB in the published literature and is derived from a single source. Therefore, its recycling efforts in the US has been unclear so as to determine the maximum opportunities for metal recovery and recycling in the face of significant demands for LAB particularly in the auto industry. Objectives: The research utilizes an evidence-based approach to: (1) determine recycling rates for lead recovery in the LAB product lifecycle for the US market; and (2) quantify and identify opportunities where lead recovery and recycling can be improved. Methods: A comprehensive electronic search of the published literature was conducted to gather information on different LAB recycling models and actual data used to calculate recycling rates based on product lifecycle for the US market to identify strategies for increasing lead recovery and recycling. Results: The electronic search yielded five models for calculating LAB recycling rates. The description of evidence was documented for each model. Furthermore, an integrated model was developed to identify and quantify the maximum opportunities for lead recovery and recycling. Results showed that recycling rates declined during the period spanning from 1999 to 2006. Opportunities were identified for recovery and recycling of lead in the LAB product lifecycle. Concluding remarks: One can deduce the following from the analyses undertaken in this report: (1) lead recovery and recycling has been stable between 1999 and 2006; (2) lead consumption has increased at an annual rate of 2.25%, thus, the values derived in this study for opportunities dealing with lead recovery and recycling underestimate the amount of lead in scrap and waste generated; and (3) the

  2. Numerical study of nozzle design for the hybrid synthetic jet actuator

    Czech Academy of Sciences Publication Activity Database

    Hsu, S.-S.; Chou, Y.-J.; Trávníček, Zdeněk; Lin, C.-F.; Wang, A. B.; Yen, R.H.

    2015-01-01

    Roč. 232, August (2015), s. 172-182 ISSN 0924-4247 R&D Projects: GA ČR GA14-08888S Institutional support: RVO:61388998 Keywords : synthetic jet * hybrid synthetic jet * numerical simulation Subject RIV: JU - Aeronautics, Aerodynamics, Aircrafts Impact factor: 2.201, year: 2015 http://www.sciencedirect.com/science/article/pii/S0924424715300091

  3. Dynamic light scattering study of the effect of Mg2+ and ATP on synthetic myosin filaments

    Science.gov (United States)

    Fujime, Satoru; Takayama, Sei-ichi

    1995-01-01

    The dynamic light scattering (DLS) method provides us with information about the apparent diffusion coefficient, Dapp, as well as the static scattering intensity, Is. For long but thin rods with length L and diameter d (i.e., KL >> 1 but Kd different from that of Is. By means of DLS were studied synthetic myosin filaments of vertebrate skeletal muscle in solution at pH 8.3. It appeared that Mg2+ ions induced lengthening and thickening of the filaments whereas ATP (and ADP) induced shortening (depolymerization) of the filaments. When ATP was added to the filament preparation in the presence of Mg2+ ions, thinning of the filaments (or splitting into subfilaments) occurred prior to shortening (depolymerization).

  4. Gamma-resonance study of the reaction of iron ions with synthetic L-dopa melanin

    Energy Technology Data Exchange (ETDEWEB)

    Bagirov, R.M.; Stukan, R.A.; Lapina, V.A.; Dontsov, A.E.; Ostrovskii, M.A.

    1986-07-01

    The reaction of Fe/sup 3 +/ and Fe/sup 2 +/ ions with synthetic L-dopa melanin, which is a model compound of natural melanin (the melanoprotein granules in the pigment epithelial cells in vertebrate and human eyes), has been studied by gamma-resonance spectroscopy. The investigations showed that L-dopa melanin is capable of effectively binding iron ions and that it displays oxidative or reducing properties with respect to Fe, depending on the composition of the subsystem of the Fe ions and the ambient pH. Trivalent Fe/sup 3 +/ ions form stronger complexes with L-dopa melanin than do Fe/sup 2 +/ ions. The coordination takes place mainly with the carboxyl groups and the amino and imino groups of the polymer. The conformational state of the polymer apparently changes as the pH is varied.

  5. NATO Advanced Study Institute on Synthetic Membranes : Science, Engineering and Applications

    CERN Document Server

    Lonsdale, H; Pinho, M

    1986-01-01

    The chapters in this book are based upon lectures given at the NATO Advanced Study Institute on Synthetic Membranes (June 26-July 8, 1983, Alcabideche, Portugal), which provided an integrated presentation of syn­ thetic membrane science and technology in three broad areas. Currently available membrane formation mechanisms are reviewed, as well as the manner in which synthesis conditions can be controlled to achieve desired membrane structures. Membrane performance in a specific separa­ tionprocess involves complex phenomena, the understanding of which re­ quires a multidisciplinary approach encompassing polymer chemistry, phys­ ical chemistry, and chemical engineering. Progress toward a global understanding of membrane phenomena is described in chapters on the principles of membrane transport. The chapters on membrane processes and applications highlight both established and emerging membrane processes, and elucidate their myriad applications. It is our hope that this book will be an enduring, comprehensi...

  6. Pneumatically Powered Drilling of Carbon Fibre Composites Using Synthetic Biodegradable Lubricating Oil: An Experimental Study

    Directory of Open Access Journals (Sweden)

    Corydon M. J. Morrell

    2018-01-01

    Full Text Available Carbon fibre composites are a key component of aircraft structures because of their enhanced material properties such as favourable strength to weight ratios when compared to metal alloys. During the assembly process of an aircraft, carbon fibre components are joined to other structures using rivets, bolts, and fasteners, and as part of the joining process, the components will need to be machined or drilled. Unlike metal alloys, composites are sensitive to heat and are vulnerable to internal structural damage from machining tools. They are also susceptible to a reduction in strength when fibres are exposed to moisture. In the machining process, carbon fibre composites may be drilled using oils to lubricate carbide machining tools. In this study, a description of the experimental apparatus is provided along with an investigation to determine the influence synthetic biodegradable lubricating oil has on drill rotational speed, drilling load, and drilling temperature when using a pneumatic drill to machine carbon fibre composite material.

  7. Study of lead pollution from automobile emissions in Khartoum

    International Nuclear Information System (INIS)

    Ibrahim, A.S.

    2002-07-01

    Aerosol and soil samples were collected from places near the main roads in Khartoum area. The samples were analyzed by energy Dispersive x-ray fluorescence (EDXRF) technique, to study the lead (Pb) concentration in air and soil near roadsides due to automobile emissions. The aim of the study was also to make a comparison with the results of previous measurements made in the same field (Ahmed, 1983) . Thee aerosol samples were taken from three sites in Khartoum area. Tuti island taken as a control area, central Khartoum as a commercial area and south of Khartoum as a residential area. Soil samples were taken from a place near Al Gurashi Park and another near Abu Hamama traffic junction in Khartoum area. The data obtained of (Pb) concentrations in the roadside air were statistically analyzed. Comparisons were made between the concentrations at the various times of the day and correlation were made with meteorological parameters. The (Pb) concentrations in the roadside soil were observed to be inversely proportional to the distance from the road and the depth from the layer of the earth. Finally, the results obtained are discussed and some recommendations are suggested. (Author)

  8. Impact of different synthetic bone fillers on healing of extraction sockets: an experimental study in dogs.

    Science.gov (United States)

    Hong, Ji-Youn; Lee, Jung-Seok; Pang, Eun-Kyoung; Jung, Ui-Won; Choi, Seong-Ho; Kim, Chong-Kwan

    2014-02-01

    The objective of this study was to elucidate the socket healing process and biodegradation of incorporating synthetic bone fillers followed by grafting of the fresh extraction socket. Third premolars in four quadrants of eight beagle dogs were extracted and randomly treated with either one of hydroxyapatite (HA), biphasic calcium phosphate (BCP), β-tricalcium phosphate (β-TCP), or no graft (C). Histologic observations and histomorphometric analysis at three zones (apical, middle, and coronal) of the socket were performed. Socket area (S) and the proportions of newly formed bone (%NB), residual biomaterials (%RB), and fibrovascular connective tissue (%FCT) at 2, 4, and 8 weeks were measured. The numbers of osteoclast-like multinucleated cells (No.OC) were also determined at the three zones. %NB was significantly higher in control group compared with the grafted groups at all healing periods. %NB of HA and BCP increased with time, whereas %RB showed different patterns that decreased in BCP, unlike the minimal change observed in HA. %NB of β-TCP showed smallest portion compared with other grafted groups at 2 and 4 weeks, however, significantly increased at 8 weeks. %RB of β-TCP was less than HA and BCP at all healing periods. Numbers of multinucleated cells were greater in BCP and β-TCP, followed by HA and smallest in control group. Within the limit of this study, bone formation of the extraction socket was delayed in the sockets grafted with synthetic bone fillers and showed different healing process according to the biodegradation patterns. © 2012 John Wiley & Sons A/S.

  9. Synthetical bone-like and biological hydroxyapatites: a comparative study of crystal structure and morphology.

    Science.gov (United States)

    Marković, Smilja; Veselinović, Ljiljana; Lukić, Miodrag J; Karanović, Ljiljana; Bračko, Ines; Ignjatović, Nenad; Uskoković, Dragan

    2011-08-01

    Phase composition, crystal structure and morphology of biological hydroxyapatite (BHAp) extracted from human mandible bone, and carbonated hydroxyapatite (CHAp), synthesized by the chemical precipitation method, were studied by x-ray powder diffraction (XRD), Fourier transform infrared (FTIR) and Raman (R) spectroscopy techniques, combined with transmission electron microscopy (TEM). Structural and microstructural parameters were determined through Rietveld refinement of recorded XRD data, performed using the FullProf computing program, and TEM. Microstructural analysis shows anisotropic extension along the [00l] crystallographic direction (i.e. elongated crystallites shape) of both investigated samples. The average crystallite sizes of 10 and 8 nm were estimated for BHAp and CHAp, respectively. The FTIR and R spectroscopy studies show that carbonate ions substitute both phosphate and hydroxyl ions in the crystal structure of BHAp as well as in CHAp, indicating that both of them are mixed AB-type of CHAp. The thermal behaviour and carbonate content were analysed using thermogravimetric and differential thermal analysis. The carbonate content of about 1 wt.% and phase transition, at near 790 °C, from HAp to β-tricalcium phosphate were determined in both samples. The quality of synthesized CHAp powder, particularly, the particle size distribution and uniformity of morphology, was analysed by a particle size analyser based on laser diffraction and field emission scanning electron microscopy, respectively. These data were used to discuss similarity between natural and synthetic CHAp. Good correlation between the unit cell parameters, average crystallite size, morphology, carbonate content and crystallographic positions of carbonate ions in natural and synthetic HAp samples was found. © 2011 IOP Publishing Ltd

  10. A synthetic study on constaining a 2D density-dependent saltwater intrusion model using electrical imaging data

    DEFF Research Database (Denmark)

    Antonsson, Arni Valur; Nguyen, Frederic; Engesgaard, Peter Knudegaard

    different hydrological conditions. The results of this synthetic study demonstrated some of the (potential) benefits of applying the electrical imaging data for calibration of seawater intrusion models. Furthermore, it also shows some of the limits this method has as well as the associated uncertainties....... Compared to conventional methods, which only give (few) point information, electrical images can give data over large spatial distances but that can be of great value for groundwater modeling purposes. The aim of this study is to investigate in a synthetic way, the applicability of using electrical images....... This study was conducted as a part of the European project ALERT (GOCE-CT-2004-505329)....

  11. A synthetic dataset for spatio-temporal scaling studies in microwave remote sensing

    Science.gov (United States)

    Ebrahimi, H.; Liu, P. W.; Chakrabarti, S.; Judge, J.

    2017-12-01

    Passive microwave missions such as the SMAP and SMOS provide Soil Moisture (SM) information on a global basis at spatial resolution of 10s of km. These products have to be downscaled to field scales of 200 m-1 km for applications in hydrology and agriculture. Unfortunately, a dense network of field measurements is typically unavailable under the satellite footprint to evaluate the spatial scaling algorithms. An effective alternative is to develop a synthetic experiment for simulating SM observations at both satellite and field scales. In this study, we develop a simulation dataset for the state of Iowa based upon our previous methodology used to conduct synthetic experiments for heterogeneous landscapes with dynamic vegetation in north central Florida. Such a dataset will allow developing and evaluating spatio-temporal scaling algorithms. The dataset is developed for 162 SMAP pixels (320km X 560km) for corn, soybean, and bare soil land covers in Iowa, during two years, 2012 and 2015, where 2012 was a drier year than 2015. The crop growth and development will be simulated with the Decision Support for Agrotechnology Transfer (DSSAT) suite of crop models. The LSP-DSSAT-MB model have been calibrated with data from the Soil Moisture Active Passive Validation Experiment-2016. During the experiment, the University of Florida observed active and passive microwave signatures and concurrent soil and vegetation conditions for growing corn and soybean from May-September (SMAPVEX16-MicroWEX). The dataset has been generated at 200m, 1km, 5km, 10km, 25km, and 36km. The results show variability of soil moisture across the region for the two years.

  12. Lead macro-encapsulation conceptual and experimental studies

    International Nuclear Information System (INIS)

    Orebaugh, E.G.

    1993-01-01

    Macro-encapsulation, the regulatory treatment for radioactively contaminated lead (mixed) waste has been conceptually and experimentally evaluated for practical application. Epoxy encapsulants molded around lead billets have proven to be exceptionally rugged, easily applied, have high radiation and chemical stability, and minimize required process equipment and production of secondary wastes. This technology can now be considered developed, and can be applied as discussed in this report

  13. Synthetic cannabis and respiratory depression.

    Science.gov (United States)

    Jinwala, Felecia N; Gupta, Mayank

    2012-12-01

    In recent years, synthetic cannabis use has been increasing in appeal among adolescents, and its use is now at a 30 year peak among high school seniors. The constituents of synthetic cannabis are difficult to monitor, given the drug's easy accessibility. Currently, 40 U.S. states have banned the distribution and use of some known synthetic cannabinoids, and have included these drugs in the Schedule I category. The depressive respiratory effect in humans caused by synthetic cannabis inhalation has not been thoroughly investigated in the medical literature. We are the first to report, to our knowledge, two cases of self-reported synthetic cannabis use leading to respiratory depression and necessary intubation.

  14. Electron microscopic and physico-chemical studies of DNA complexes with synthetic oligopeptides: binding specificity and DNA compact structures.

    Science.gov (United States)

    Vengerov, Y Y; Semenov, T E; Surovaya, A N; Sidorova NYu; Streltsov, S A; Khorlin, A A; Zhuze, A L; Gursky, G V

    1988-10-01

    Binding to DNA of two synthetic peptides, Val-Thr-Thr-Val-Val-NH-NH-Dns and Thr-Val-Thr-Lys-Val-Gly-Thr-Lsy-Val-Gly-Thr-Val-Val-NH-NH-Dns (where Dns is a residue of 5-dimethylaminonaphthalene-1-sulfonic acid), has been studied by circular dichroism, electron microscopy and fluorescence methods. It has been found that these two peptides can self-associate in aqueous solution as follows from the fact that concentration-dependent changes are observed in the UV absorbance and fluorescence spectra. The two peptides can bind to DNA both in self-associated and monomeric forms. The pentapeptide in the beta-associated form binds more strongly to poly(dG).poly(dC) than to poly[d(A-C)].poly[d(G-T)] and poly(dA).poly(dT) whereas the tridecapeptide exhibits an opposite order of preferences binding more strongly to poly[d(A-C)].poly[d(G-T)] and poly(dA).poly(dT) than to poly(dG).poly(dC). Binding is a cooperative process which is accompanied by the DNA compaction at peptide/DNA base pair ratios greater than 1. At the initial stage of the compaction process, the coalescence of DNA segments covered by bound peptide molecules leads to the formation of DNA loops stabilized by the interaction between peptide molecules bound to different DNA segments. Further increase in the peptide/DNA ratio leads to the formation of rod-like structures each consisting of two or more double-stranded DNA segments. The final stage of the compaction process involves folding of fibrillar macromolecular complexes into a globular structure containing only one DNA molecule.

  15. Feasibility study of thermal energy harvesting using lead free pyroelectrics

    Science.gov (United States)

    Karim, Hasanul; Sarker, Md Rashedul H.; Shahriar, Shaimum; Arif Ishtiaque Shuvo, Mohammad; Delfin, Diego; Hodges, Deidra; (Bill Tseng, Tzu-Liang; Roberson, David; Love, Norman; Lin, Yirong

    2016-05-01

    Energy harvesting has significant potential for applications in energizing wireless sensors and charging energy storage devices. To date, one of the most widely investigated materials for mechanical and thermal energy harvesting is lead zirconate titanate (PZT). However, lead has detrimental effects on the environment and on health. Hence, alternative materials are required for this purpose. In this paper, a lead free material, lithium niobate (LNB) is investigated as a potential material for pyroelectric energy harvesting. Although its theoretical pyroelectric properties are lower compared to PZT, it has better properties than other lead free alternatives such as ZnO. In addition, LNB has a high Curie temperature of about 1142 °C, which makes it applicable for high temperature energy harvesting, where other pyroelectric ceramics are not suitable. Herein, an energy harvesting and storage system composed of a single crystal LNB and a porous carbon-based super-capacitor was investigated. It is found that with controlled heating and cooling, a single wafer of LNB (75 mm diameter and 0.5 mm thickness) could generate 437.72 nW cm-3 of power and it could be used to charge a super-capacitor with a charging rate of 2.63 mV (h cm3)-1.

  16. Rubidium-strontium and uranium-lead isotopic age studies

    International Nuclear Information System (INIS)

    Loveridge, W.D.

    1980-01-01

    Rubidium-strontium whole rock isochron ages and initial 87 Sr/ 86 Sr ratios and uranium-lead ages on zircon from suites of samples selected from localities across Canada are presented. Descriptions of the geological probelms and interpretations of the measured ages are included. Laboratory age determination methods and techniques are described or referenced. (auth)

  17. Childhood lead poisoning on the US-Mexico border: a case study in environmental health nursing lead poisoning.

    Science.gov (United States)

    Alvarez Amaya, M; Ackall, G; Pingitore, N; Quiroga, M; Terrazas-Ponce, B

    1997-12-01

    Human exposure to environmental hazards is a major public health problem along the US-Mexico border due to socioeconomic, cultural and political factors. Childhood lead exposure is endemic in areas of extreme poverty and substandard housing. Hispanic children of indigent, poorly-educated, disenfranchised families are at disproportionate risk. Risk management is contingent upon consideration of the interrelationships between socioeconomics, politics, and culture. This case study explains childhood lead poisoning in a colonia family living at subsistence level from such a perspective. The purpose of the study was to identify, explain, and ameliorate lead exposure pathways. Case study methodology was used to support or refute the proposition that these children were exposed to occupational lead. The children were the study sampling unit and the family a subunit. An embedded single case explanatory design was appropriate. Data were collected from exposure surveys, environmental and blood specimens, and review of medical records. Pattern-matching and explanation-building techniques were used to analyze data. The study illustrated how extreme poverty, lack of access to health services, social isolation, language and legal barriers, and hazardous occupations may be singularly common risk factors for Hispanic children on the US-Mexico border. The study is pertinent to public health nurses who work with this population.

  18. Natural vs synthetic auxin: studies on the interactions between plant hormones and biological membrane lipids.

    Science.gov (United States)

    Flasiński, Michał; Hąc-Wydro, Katarzyna

    2014-08-01

    Analysis of the interactions between two representatives of plant hormones: synthetic (1-naphthaleneacetic acid, NAA) as well as natural (indole-3-acetic acid, IAA) and phospholipids occurring in biological membrane of both plant and animal cells was the subject of present studies. The aim of undertaken experiments was to elucidate the problem of direct influence of these plant growth regulators on phosphatidylcholines (PCs) and phosphatidylethanolamines (PEs) in monolayers at the air/water solution interface. The studied phospholipids differ not only as regards the structure of polar head-groups but also in the length of hydrophobic chains as well as their saturation degree. These differences result also in the main properties and functions of these phospholipids in biomembranes. The analysis of the results was based on the characteristics of the surface pressure (π)--area (A) isotherms registered for monolayers spread on the subphase containing plant hormone and as a reference on the surface of pure water. Moreover, as a complementary technique, Brewster angle microscopy was applied for the direct visualization of the investigated surface films. The obtained results revealed that auxins effectively influence phospholipids monolayers, regardless of the lipid structure, at the concentration of 10(-4)M. It was found that for this concentration, the influence of auxins was visibly larger in the case of PCs as compared to PEs. On the other hand, in the case of auxins solution of ≤ 10(-5)M, the observed trend was opposite. Generally, our studies showed that the natural plant hormone (IAA) interacts with the investigated lipid monolayers stronger than its synthetic derivative (NAA). The reason of these differences connects with the steric properties of both auxins; namely, the naphthalene ring of NAA molecule occupies larger space than the indole system of IAA. Therefore molecules of the latter compound penetrate easier into the region of phospholipids׳ polar head

  19. Oral two-generation reproduction toxicity study with NM-200 synthetic amorphous silica in Wistar rats.

    Science.gov (United States)

    Wolterbeek, André; Oosterwijk, Thies; Schneider, Steffen; Landsiedel, Robert; de Groot, Didima; van Ee, Renz; Wouters, Mariëlle; van de Sandt, Han

    2015-08-15

    Synthetic amorphous silica (SAS) like NM-200 is used in a wide variety of technological applications and consumer products. Although SAS has been widely investigated the available reproductive toxicity studies are old and do not cover all requirements of current OECD Guidelines. As part of a CEFIC-LRI project, NM-200 was tested in a two-generation reproduction toxicity study according to OECD guideline 416. Male and female rats were treated by oral gavage with NM-200 at dose levels of 0, 100, 300 and 1000mg/kg bw/day for two generations. Body weight and food consumption were measured throughout the study. Reproductive and developmental parameters were measured and at sacrifice (reproductive) organs and tissues were sampled for histopathological analysis. Oral administration of NM-200 up to 1000mg/kg bw/day had no adverse effects on the reproductive performance of rats or on the growth and development of the offspring into adulthood for two consecutive generations. The NOAEL was 1000mg/kg body weight per day. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Experimental study on the adsorptive-distillation for dehydration of ethanol-water mixture using natural and synthetic zeolites

    Science.gov (United States)

    Megawati, Wicaksono, D.; Abdullah, M. S.

    2017-03-01

    This research studied adsorptive-distillation (AD) for dehydration of ethanol-water mixture using natural and synthetic zeolites as adsorbent for ethanol purification. Especially, the effect of purification time is recorded and studied to evaluate performance of designed AD equipment. This AD was performed in a batch condition using boiling flask covered with heating mantle and it was maintained at 78°C temperature and 1 atm pressure. The initial ethanol volume was 300 mL with 93.8% v/v concentration. The synthetic zeolite type used was zeolite 3A. The flowed vapour was condensed using water as a cooling medium. Every 5 minutes of time duration the samples were collected until the vapour could not be condensed in that condition and then be analyzed its concentration using Gas-Chromatography. Experiment shows that the designed AD equipment could increase ethanol concentration at first 5 minutes with highest ethanol concentration achieved using synthetic zeolite (97.47% v/v). However, ethanol concentration from AD process using natural zeolite only reached 96.5% v/v. Thus, synthetic zeolite as adsorbent could pass azeotropic point, but natural zeolite fail. The ratio of adsorbed water per adsorbent for natural and synthetic zeolites are about 0.023 and 0.056 gwater/gads, respectively, at 50 minutes of time. Finally, synthetic zeolite (at 55 minutes the value of C/C0 is about 0.85 and the average outlet water concentration is 4.70 mole/L) as adsorbent for AD of ethanol water is better than natural zeolite (at 55 minutes the value of C/C0 is about 0.63 and the average outlet water concentration is 6.43 mole/L).

  1. The Effect of Loading Rate on Hydraulic Fracturing in Synthetic Granite - a Discrete Element Study

    Science.gov (United States)

    Tomac, I.; Gutierrez, M.

    2015-12-01

    Hydraulic fracture initiation and propagation from a borehole in hard synthetic rock is modeled using the two dimensional Discrete Element Method (DEM). DEM uses previously established procedure for modeling the strength and deformation parameters of quasi-brittle rocks with the Bonded Particle Model (Itasca, 2004). A series of simulations of laboratory tests on granite in DEM serve as a reference for synthetic rock behavior. Fracturing is enabled by breaking parallel bonds between DEM particles as a result of the local stress state. Subsequent bond breakage induces fracture propagation during a time-stepping procedure. Hydraulic fracturing occurs when pressurized fluid induces hoop stresses around the wellbore which cause rock fracturing and serves for geo-reservoir permeability enhancement in oil, gas and geothermal industries. In DEM, a network of fluid pipes and reservoirs is used for mathematical calculation of fluid flow through narrow channels between DEM particles, where the hydro-mechanical coupling is fully enabled. The fluid flow calculation is superimposed with DEM stress-strain calculation at each time step. As a result, the fluid pressures during borehole pressurization in hydraulic fracturing, as well as, during the fracture propagation from the borehole, can be simulated. The objective of this study is to investigate numerically a hypothesis that fluid pressurization rate, or the fluid flow rate, influences upon character, shape and velocity of fracture propagation in rock. The second objective is to better understand and define constraints which are important for successful fracture propagation in quasi-brittle rock from the perspective of flow rate, fluid density, viscosity and compressibility relative to the rock physical properties. Results from this study indicate that not only too high fluid flow rates cause fracture arrest and multiple fracture branching from the borehole, but also that the relative compressibility of fracturing fluid and

  2. Struvite Precipitation and Phosphorous Removal from Urine Synthetic Solution: Reaction Kinetic Study

    Directory of Open Access Journals (Sweden)

    Marwa Saied Shalaby

    2015-03-01

    Full Text Available Phosphorus, like oil, is a non-renewable resource that must be harvested from finite resources in the earth’s crust. An essential element for life, phosphorus is becoming increasingly scarce, contaminated, and difficult to extract. Struvite or magnesium ammonium phosphate (MgNH4PO4.6H2O is a white, crystalline phosphate mineral that can be used as a bio-available fertilizer. The main objective of this research is to indicate the most important operating parameters affecting struvite precipitation by means of chemical reaction kinetics. The present study explores struvite precipitation by chemical method under different starting molar ratios, pH and SSR. It is shown that an increase of starting Mg: PO4: NH4 with respect to magnesium (1.6:1:1 strongly influences the growth rate of struvite and so the efficiency of the phosphate removal. This was attributed to the effect of magnesium on the struvite solubility product and on the reached supersaturation Super Saturation Ratio at optimum starting molar ratio and pH. It was also shown, by using chemical precipitation method that the determined Super Saturation Ratio (SSR values of struvite, at 8, 8.5, 9, 9.5 and 10 are 1.314, 4.29, 8.89, 9.87 and 14.89 respectively are close to those presented in the literature for different origins of wastewater streams. The results show that SSR , pH, and starting molar ratio strongly influences the kinetics of precipitation and so phosphorous removal to reach 93% removal percent , 5.95 mg/lit as a minimum PO4 remained in solution, and 7.9 gm precipitated struvite from feed synthetic solution of 750 ml . The product was subjected to chemical analysis by means of EDIX-FTIR, SEM and XRD showing conformity with published literature. First-order kinetics was found to be sufficient to describe the rate data. The rates increased with increasing pH and so SSR and the apparent rate constants for the reaction were determined. © 2015 BCREC UNDIP. All rights reserved

  3. Orientation modulation of a synthetic polypeptide in self-assembled monolayers: a TOF-SIMS study.

    Science.gov (United States)

    Leufgen, Kirsten; Mutter, Manfred; Vogel, Horst; Szymczak, Wilfried

    2003-07-23

    Structure and orientation of molecules are key properties of functionalized surfaces. Using time-of-flight secondary ion mass spectrometry (TOF-SIMS), here we investigate how to modulate these parameters upon the immobilization process varying the conditions of self-assembly. The molecule of interest, a template-assembled synthetic protein (TASP), consists of a central peptide ring with orthogonally arranged residues. Thioalkane chains allow the directed self-assembly of the molecule on a gold surface; four serine residues on the opposite side of the ring can be used as anchoring sites for various functional sensing molecules. The TASP conformation and its orientation in self-assembled monolayers (SAMs) play a central role for the accessibility of these serine residues. To study the influence of the self-assembly conditions, two series of samples were prepared. Pure TASP monolayers of different surface densities are compared to mixed TASP/alkanethiol monolayers prepared by sequential adsorption varying sequence and particular incubation times as well as by coadsorption modifying incubation times and TASP/alkanethiol mass ratios. Switching the TASP orientation from a state where the molecules are lying flat on the surface to an upright orientation turned out to be possible by inserting the TASP into a preformed alkanethiol monolayer of an appropriate surface density. This study demonstrates that TOF-SIMS is an excellent tool not only to investigate the surface composition, but also the molecular structure of functionalized surfaces.

  4. Multidimensional approaches for studying plant defence against insects: from ecology to omics and synthetic biology.

    Science.gov (United States)

    Barah, Pankaj; Bones, Atle M

    2015-02-01

    The biggest challenge for modern biology is to integrate multidisciplinary approaches towards understanding the organizational and functional complexity of biological systems at different hierarchies, starting from the subcellular molecular mechanisms (microscopic) to the functional interactions of ecological communities (macroscopic). The plant-insect interaction is a good model for this purpose with the availability of an enormous amount of information at the molecular and the ecosystem levels. Changing global climatic conditions are abruptly resetting plant-insect interactions. Integration of discretely located heterogeneous information from the ecosystem to genes and pathways will be an advantage to understand the complexity of plant-insect interactions. This review will present the recent developments in omics-based high-throughput experimental approaches, with particular emphasis on studying plant defence responses against insect attack. The review highlights the importance of using integrative systems approaches to study plant-insect interactions from the macroscopic to the microscopic level. We analyse the current efforts in generating, integrating and modelling multiomics data to understand plant-insect interaction at a systems level. As a future prospect, we highlight the growing interest in utilizing the synthetic biology platform for engineering insect-resistant plants. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  5. Study of the antibacterial and antifungal activities of synthetic benzyl bromides, ketones, and corresponding chalcone derivatives.

    Science.gov (United States)

    Shakhatreh, Muhamad Ali K; Al-Smadi, Mousa L; Khabour, Omar F; Shuaibu, Fatima A; Hussein, Emad I; Alzoubi, Karem H

    2016-01-01

    Several applications of chalcones and their derivatives encouraged researchers to increase their synthesis as an alternative for the treatment of pathogenic bacterial and fungal infections. In the present study, chalcone derivatives were synthesized through cross aldol condensation reaction between 4-( N , N -dimethylamino)benzaldehyde and multiarm aromatic ketones. The multiarm aromatic ketones were synthesized through nucleophilic substitution reaction between 4-hydroxy acetophenone and benzyl bromides. The benzyl bromides, multiarm aromatic ketones, and corresponding chalcone derivatives were evaluated for their activities against eleven clinical pathogenic Gram-positive, Gram-negative bacteria, and three pathogenic fungi by the disk diffusion method. The minimum inhibitory concentration was determined by the microbroth dilution technique. The results of the present study demonstrated that benzyl bromide derivatives have strong antibacterial and antifungal properties as compared to synthetic chalcone derivatives and ketones. Benzyl bromides (1a and 1c) showed high ester activity against Gram-positive bacteria and fungi but moderate activity against Gram-negative bacteria. Therefore, these compounds may be considered as good antibacterial and antifungal drug discovery. However, substituted ketones (2a-b) as well as chalcone derivatives (3a-c) showed no activity against all the tested strains except for ketone (2c), which showed moderate activity against Candida albicans .

  6. Cross-Sectional Study on Nonmalignant Respiratory Morbidity due to Exposure to Synthetic Amorphous Silica.

    Science.gov (United States)

    Taeger, Dirk; McCunney, Robert; Bailer, Ursula; Barthel, Kai; Küpper, Ulrich; Brüning, Thomas; Morfeld, Peter; Merget, Rolf

    2016-04-01

    The aim of this study was to assess the health impact of chronic exposure to synthetic amorphous silica (SAS) on nonmalignant respiratory morbidity. We used multiple linear and logistic regression models and Monte Carlo multimodel analyses of two exposure scenarios to evaluate the effect of cumulative exposure to inhalable SAS dust on symptoms, spirometry, and chest films in 462 male workers from five German SAS-producing plants. Exposure to SAS was associated with a reduction in forced vital capacity (FVC) in one of the two exposure scenarios but had no effect on forced expiratory volume in 1 second (FEV1) or FEV1/FVC in either exposure scenario. Monte Carlo analysis indicated a decline in FVC of -11 mL per 10 mg/m-years exposure (-6 to -0.4). Chest films showed no evidence of pneumoconiosis. This study provides limited evidence of minor dose-related effects of chronic exposure to SAS on lung function.

  7. Feasibility Study of Synthetic Aperture Radar - Adaptability of the Payload to KOMPSAT Platform

    Directory of Open Access Journals (Sweden)

    Young-Soo Kim

    2002-09-01

    Full Text Available Synthetic Aperture Radar (SAR has been used for mapping the surface geomorphology of cloudy planets like Venus as well as the Earth. The cloud-free Mars is also going to be scanned by SAR in order to detect buried water channels and other features under the very shallow subsurface of the ground. According to the 'Mid and Long-term National Space Development Plan' of Korea, SAR satellites, in addition to the EO (Electro-Optical satellites, are supposed to be developed in the frame of the KOMPSAT (Korean Multi-Purpose Satellite program. Feasibility of utilizing a SAR payload on KOMPSAT platform has been studied by KARI in collaboration with Astrium U.K. The purpose of the SAR program is Scientific and Civil applications on the Earth. The study showed that KOMPSAT-2 platform can accommodate a small SAR like Astrium's MicroSAR. In this paper, system aspects of the satellite design are presented, such as mission scenario, operation concept, and capabilities. The spacecraft design is also discussed and conclusion is followed.

  8. Metal corrosion in polychrome baroque lead sculptures: a case study

    OpenAIRE

    Faria,Dalva L. A. de; Puglieri,Thiago S.; Souza,Luiz Antonio C.

    2013-01-01

    Polychrome lead sculptures from Oratory Museum in Ouro Preto (Minas Gerais, Brazil) kept inside a glass showcase were severely degraded. The formed corrosion products were analyzed by X-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy dispersive X-ray fluorescence (EDX) and Raman microscopy and proved to be mostly Pb carbonates and formates. Although carbonate is a very common finding in Pb atmospheric corrosion, Pb formates ...

  9. Study on the effect of lead and lead compounds as pollutants on traffic air and traffic policemen

    International Nuclear Information System (INIS)

    Abd Alrhman, Heba Elyas Khider

    2009-05-01

    This study was conducted in Khartoum state to determine the magnitude of air pollution, resulting from traffic density, due to lead and lead compounds which had been used as additives for gasoline in the form of tetra-ethyl and tetra methyl lead. The level of lead in ambient air and SPM was determined in 14 samples taken randomly at the intersections and entrances to the bridges using personal sampler (Cassella. UK). The mean concentration of suspended particulate matter (SPM) was found to be 5.77+4.04 mg/m 3 . with range between 0.85-12.50 mg/m 3 including three sites above the limit of 10 mg/m 3 allowed. The samples were analyzed with Atomic Absorption Spectrophotometer for their lead content. The average concentration of lead in the sites is found to be 0.1937±0.1768 mg/m 3 . With range between 0.000-0.5166 mg/m 3 . The concentrations in seven sites were above the limit of 0.15 mg/m 3 permitted internationally. The impact of lead pollution on traffic police men was measured by analyzing blood lead concentration of 30 members exposed to traffic air pollution, from the three cities and (10 samples) from non-exposed ( control). It was found to be 2.4601±1.4065μg/100 ml and 0.3944±1.2471 μg/ 100 ml respectively. The data analysis by used SPSS program. There is no significant difference between the two groups. A questionnaire was designed to find out some data about the exposed members including their knowledge of impact, range of age, duration of their service as traffic police, their previous work, and complaints from some of the health effects. The findings were: average age mean of 35.9 ±7.7 years, 47.48% worked for periods of more than 20 years, 74.19% did not work before joining the traffic police, 51.6% of them believe that there is a problem of high level of air pollution, 45.2% medium and 3.2%, pollution is low. As habits 38.71% are smokers. As for health complains, 61.29% have various complains of headaches, fatigue, abdominal, hypertension and anemia

  10. Subacute inhalation toxicity study of synthetic amorphous silica nanoparticles in Sprague-Dawley rats.

    Science.gov (United States)

    Shin, Jae Hoon; Jeon, KiSoo; Kim, Jin Kwon; Kim, Younghun; Jo, Mi Seong; Lee, Jong Seong; Baek, Jin Ee; Park, Hye Seon; An, Hyo Jin; Park, Jung Duck; Ahn, Kangho; Oh, Seung Min; Yu, Il Je

    Synthetic amorphous silica nanoparticles (SiNPs) are one of the most applied nanomaterials and are widely used in a broad variety of industrial and biomedical fields. However, no recent long-term inhalation studies evaluating the toxicity of SiNPs are available and results of acute studies are limited. Thus, we conducted a subacute inhalation toxicity study of SiNPs in Sprague-Dawley rats using a nose-only inhalation system. Rats were separated into four groups and target concentrations selected in this study were as follows: control (fresh air), low- (0.407 ± 0.066 mg/m 3 ), middle- (1.439 ± 0.177 mg/m 3 ) and high-concentration group (5.386 ± 0.729 mg/m 3 ), respectively. The rats were exposed to SiNPs for four consecutive weeks (6 hr/day, 5 days/week) except for control group of rats which received filtered fresh air. After 28-days of inhalation exposure to SiNPs, rats were sacrificed after recovery periods of one, seven and 28 days. Although there were minimal toxic changes such as temporary decrease of body weight after exposure, increased levels of red blood cells (RBCs) and hemoglobin (Hb) concentration, the lung histopathological findings and inflammatory markers in bronchoalveolar lavage (BAL) fluid including polymorphonuclear (PMN) leukocyte, lactate dehydrogenase (LDH), albumin and protein did not show significant changes at any recovery period. The results of this study suggest that the subacute inhalation of SiNPs had no toxic effects on the lung of rats at the concentrations and selected time points used in this study.

  11. Synthetic Cannabinoid Use in a Psychiatric Patient Population: A Pilot Study.

    Science.gov (United States)

    Welter, Stella; Lücke, Caroline; Lam, Alexandra Philomena; Custal, Christina; Moeller, Sebastian; Sörös, Peter; Thiel, Christiane M; Philipsen, Alexandra; Müller, Helge H O

    2017-01-01

    Consumption of natural cannabis (NC) and synthetic cannabinoids (SCs) has been associated with psychotic disorders. We compared the prevalence of use, consumer profiles, and psychosis-inducing potential of NC and SCs in a specific high-risk population. This prospective pilot study included 332 patients (18-64 years, mean 36.83, SD 13.33). Patients' sociodemographics and medical histories as well as illicit substance use and psychiatric symptom histories were collected using a drug consumption survey that assessed the use of new psychoactive substances and the Psychotic Symptoms Interview. In total, 7.2% of all patients, 10.6% of psychotic patients, and 4.5% of nonpsychotic patients reported SC consumption. Compared with SCs, NC was consumed much more frequently by its users (mean 222.73, SD 498.27). NC and SC use induced persistent psychosis. Psychotic symptoms were first experienced by patients with a history of NC or SC use during intoxication and persisted after cessation (>1 year) of drug use. Positive and negative symptoms tended to be more severe in SC and NC users, respectively. NC and SCs may cause different symptom clusters. These relationships should be further evaluated. © 2017 S. Karger AG, Basel.

  12. An Internet Study of User's Experiences of the Synthetic Cathinone 4-Methylethcathinone (4-MEC).

    Science.gov (United States)

    Van Hout, Marie Claire

    2014-01-01

    Abstract A synthetic cathinone called 4-methylethcathinone (4-MEC) emerged online in 2010, and was cyber-marketed to be a replacement for mephedrone. The study aimed to present user experiences of 4-MEC as reported on the Internet, with a focus on user profiles, sourcing and product characteristics, routes of administration, dosage, positive and undesirable effects, and comparisons to mephedrone. Twenty-three individual, anonymous trip reports of the sole use of 4-MEC, and 112 screenshots of general 4-MEC user discussion boards, were taken from a purposeful sample of public drug-related sites. A content textual analysis was conducted on extracted qualitative information and produced 41 categories compiled into five general themes: "Type of 4-MEC user"; "Sourcing, informed decision making, product characteristics, and quality assurance"; "Routes of administration, gauging of dosage, and consumption of other drugs"; "Time course effects and outcomes"; and "Comparisons with mephedrone." 4-MEC is sold as white beads, crystalline shards, or green balls. User motives centered on curiosity, pricing, and ease of web sourcing. Oral, nasal, injecting, eyeball, and rectal routes of administration were described. Testing for purity, "allergy testing," and gauging of dosage were common. Users described euphoric but short-lived effects, with little comedown. Continued research is vital to inform harm reduction.

  13. Full Polarimetric Synthetic Aperture Radar (SAR) Data for ionosphere observation - A comparative study

    Science.gov (United States)

    Mohanty, S.; Singh, G.

    2017-12-01

    Ionosphere, predominantly, govern the propagation of radio waves, especially at L-band and lower frequencies. Small-scale, rapid fluctuations in the electron density, termed as scintillation phenomenon, cause rapid variations in signal amplitude and phase. Scintillation studies have been done using ground-based radio transmitter and beacon GPS signals. In this work, attempt has been made to utilize full polarimetric synthetic aperture radar (SAR) satellite signal at L-band (1.27 GHz) to develop a new measurement index for SAR signal intensity fluctuation. Datasets acquired from Japan's latest Advanced Land Observation Satellite (ALOS)-2 over the Indian subcontinent on two different dates, with varying ionospheric activities, have been utilized to compare the index. A 20% increase in the index values for a scintillation-affected day has been observed. The result coincides with the nature of ionospheric scintillation pattern typically observed over the equatorial belt. Total electron content values, for the two dates of acquisition, obtained from freely available Ionosphere Exchange (IONEX) data have been used to validate the varying ionospheric activities as well as the trend in index results. Another interesting finding of the paper is the demarcation of the equatorial anomaly belt. The index values are comparatively higher at these latitudes on a scintillation-affected day. Furthermore, the SAR signal intensity fluctuation index has great potential in being used as a preliminary measurement index to identify low frequency SAR data affected by ionospheric scintillation.

  14. Study on sorption capacity and characterization of Sr2+ on synthetic zeolite

    International Nuclear Information System (INIS)

    Wang Jinming; Yi Facheng

    2010-01-01

    Sr 2+ adsorption capacity of synthetic zeolite(ZF) are studied with the intermittence method, and ZF adsorbed the Sr 2+ is characterized and analyzed by XRD, as a reference for the evaluation of the disposal effectiveness of low and medium radwastes. The results show that Sr 2+ adsorption capacity of ZF is good, and the equilibrium time for ZF to adsorb Sr 2+ is in range of 5-14 days. Sr 2+ concentration has the greatest effect on ZF adsorption capacity,and the medium,temperature and pH value of the solution also have effect on ZF adsorption capacity. With the augment of Sr 2+ concentration,the Sr 2+ equilibrium adsorption quantity of ZF increases,but the equilibrium adsorption rate and equilibrium adsorption ratio decreases. Sr 2+ adsorption capacity of ZF improves with the augment of pH value. Sr 2+ adsorption capacity of ZF is complicate and varies with the different ion, concentration and other components in the medium solution. Sr 2+ adsorption capacity of ZF increases with the augment of temperature. As a whole, when Sr 2+ concentration in the solution is 0.005mol/L, the pH value of the solution, and the temperature of medium and solution have less effect on the Sr 2+ adsorption capacity of ZF, and the unit cell parameter of ZF adsorbed Sr 2+ decreases. (authors)

  15. A molecular dynamics and circular dichroism study of a novel synthetic antimicrobial peptide

    International Nuclear Information System (INIS)

    Rodina, N P; Yudenko, A N; Terterov, I N; Eliseev, I E

    2013-01-01

    Antimicrobial peptides are a class of small, usually positively charged amphiphilic peptides that are used by the innate immune system to combat bacterial infection in multicellular eukaryotes. Antimicrobial peptides are known for their broad-spectrum antimicrobial activity and thus can be used as a basis for a development of new antibiotics against multidrug-resistant bacteria. The most challengeous task on the way to a therapeutic use of antimicrobial peptides is a rational design of new peptides with enhanced activity and reduced toxicity. Here we report a molecular dynamics and circular dichroism study of a novel synthetic antimicrobial peptide D51. This peptide was earlier designed by Loose et al. using a linguistic model of natural antimicrobial peptides. Molecular dynamics simulation of the peptide folding in explicit solvent shows fast formation of two antiparallel beta strands connected by a beta-turn that is confirmed by circular dichroism measurements. Obtained from simulation amphipatic conformation of the peptide is analysed and possible mechanism of it's interaction with bacterial membranes together with ways to enhance it's antibacterial activity are suggested

  16. Synthetic oils

    Science.gov (United States)

    Hatton, R. E.

    1973-01-01

    Synthetic lubricants are discussed by chemical class and their general strengths and weaknesses in terms of lubrication properties are analyzed. Comparative ratings are given for 14 chemical classes and are used as a guide for lubricant selection. The effects of chemical structure on the properties of the lubricant are described with special emphasis on thermal stability. The diversity of synthetic lubricants which is provided by the wide range of properties permits many applications, some of which are reported.

  17. Synthetic Brassica napus L.: Development and Studies on Morphological Characters, Yield Attributes, and Yield

    Directory of Open Access Journals (Sweden)

    M. A. Malek

    2012-01-01

    Full Text Available Brassica napus was synthesized by hybridization between its diploid progenitor species B. rapa and B. oleracea followed by chromosome doubling. Cross with B. rapa as a female parent was only successful. Among three colchicine treatments (0.10, 0.15, and 0.20%, 0.15% gave the highest success (86% of chromosome doubling in the hybrids (AC; 2=19. Synthetic B. napus (AACC, 2=38 was identified with bigger petals, fertile pollens and seed setting. Synthetic B. napus had increased growth over parents and exhibited wider ranges with higher coefficients of variations than parents for morphological and yield contributing characters, and yield per plant. Siliqua length as well as beak length in synthetic B. napus was longer than those of the parents. Number of seeds per siliqua, 1000-seed weight and seed yield per plant in synthetic B. napus were higher than those of the parents. Although flowering time in synthetic B. napus was earlier than both parents, however the days to maturity was little higher over early maturing B. rapa parent. The synthesized B. napus has great potential to produce higher seed yield. Further screening and evaluation is needed for selection of desirable genotypes having improved yield contributing characters and higher seed yield.

  18. Removal of phenol from synthetic wastewater using carbon-mineral composite: Batch mechanisms and composition study

    Science.gov (United States)

    Kamaruddin, Mohamad Anuar; Alrozi, Rasyidah; Aziz, Hamidi Abdul; Han, Tan Yong; Yusoff, Mohd Suffian

    2017-09-01

    This study investigates the treatability of composite adsorbent made from waste materials and minerals which is widely available in Malaysia. The composite adsorbent was prepared based on wet attrition method which focuses on the determination of optimum dosage of each of raw materials amount by conventional design of experiment work. Zeolite, activated carbon, rice husk and limestone were ground to obtained particle size of 150 µm. 45.94% zeolite, 15.31% limestone, 4.38% activated carbon, 4.38% rice husk carbon and 30% of ordinary Portland cement (OPC). The mixture was mixed together under pre-determined mixing time. About 60% (by weight) of water was added and the mixture paste was allowed to harden for 24 hours and then submersed in water for three days for curing. Batch experimental study was performed on synthetic dissolving a known amount of solid crystal phenol with distilled water into the volumetric flasks. From the batch experimental study, it was revealed that the optimum shaking speed for removal of phenol was 200 rpm. The removal efficiency was 65%. The optimum shaking time for removing phenol was 60 minutes; the percentage achieved was 55%. The removal efficiency increased with the increased of the amount of composite adsorbent. The removal efficiency for optimum adsorbent dosage achieved 86%. Furthermore, the influence of pH solution was studied. The optimum pH for removing phenol was pH 6, with the removal percentage of 95%. The results implies that carbon-mineral based composite adsorbent is promising replacement for commercial adsorbent that provides alternative source for industrial adsorption application in various types of effluent treatment system.

  19. Lead Exposure: A Summary of Global Studies and the Need for New Studies from Saudi Arabia

    Directory of Open Access Journals (Sweden)

    A. P. Shaik

    2014-01-01

    Full Text Available Lead poisoning (plumbism can cause irreversible genetic and reproductive toxicity, hematological effects, neurological damage, and cardiovascular effects. Despite many efforts to minimize lead poisoning, it continues to be a major health concern in many developing and developed countries. Despite efforts to control lead exposure and toxicity, serious cases of lead poisoning increasingly occur as a result of higher vehicular traffic and industrialization. The biomarkers for identification of genetic susceptibility to a particular disease are useful to identify individuals who are at risk for lead poisoning. Although many such studies have been taken up elsewhere, very few studies were performed in Saudi Arabia to assess susceptibility to lead poisoning. This indicates an urgent need for testing of susceptible individuals. The present paper was planned to understand the genetic susceptibility to lead toxicity in the various population studies conducted worldwide and also to correlate it with the current scenario in Saudi Arabia. Such studies are necessary for appropriate precautions in terms of diet and avoiding exposure to be used in order to prevent adverse health effects.

  20. A synthetic approach to compare the large truck crash causation study and naturalistic driving data.

    Science.gov (United States)

    Hickman, Jeffrey S; Hanowski, Richard J; Bocanegra, Joseph

    2018-03-01

    Truck crashes represent a significant problem on our nation's highways. There is a great opportunity to learn about crash causation by analyzing and comparing the Large Truck Crash Causation Study (LTCCS) and naturalistic driving (ND) data. These data sets provide in-depth information, but have contrasting strengths and weaknesses. The LTCCS contains information on high-severity crashes (crashes and fatal crashes), but relied on data collected during crash investigations. The LTCCS identified principal driver errors in the crash, such as the Critical Reason, but not detailed behaviors or scenario sequences. The ND data sets relate primarily to non-crashes that are detectable from dynamic vehicle events, such as hard braking, swerve, etc., provide direct video observations of the driver and the surrounding driving scene and precise information on driver inputs (kinematics) and captured events, and provide certain types of exposure data that cannot easily be obtained using crash reconstruction data. The ND data are collected continuously, thereby capturing both safety-critical events and normative driving (i.e., baseline). The current project evaluated large-truck crash data from the LTCCS and two large-truck ND data sets, the Naturalistic Truck Driving Study and the Drowsy Driver Warning System Field Operational Test. A synthetic risk ratio analysis on the associated factor, Following Too Closely, indicated that truck drivers in the LTCCS were 1.34 times more likely to be involved in a crash, than an ND crash-relevant conflict, if they were following too closely (i.e., tailgating). Given several caveats noted in the paper, this study suggests it's possible to use the ND data set to calculate the exposure of a given behavior and use the LTCCS data set to calculate the crash exposure to the same behavior. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Targeted expression of redesigned and codon optimised synthetic gene leads to recrystallisation inhibition and reduced electrolyte leakage in spring wheat at sub-zero temperatures.

    Science.gov (United States)

    Khanna, Harjeet K; Daggard, Grant E

    2006-12-01

    Antifreeze proteins (AFPs) adsorb to ice crystals and inhibit their growth, leading to non-colligative freezing point depression. Crops like spring wheat, that are highly susceptible to frost damage, can potentially be made frost tolerant by expressing AFPs in the cytoplasm and apoplast where ice recrystallisation leads to cellular damage. The protein sequence for HPLC-6 alpha-helical antifreeze protein from winter flounder was rationally redesigned after removing the prosequences in the native protein. Wheat nuclear gene preferred amino acid codons were used to synthesize a recombinant antifreeze gene, rAFPI. Antifreeze protein was targeted to the apoplast using a Murine leader peptide sequence from the mAb24 light chain or retained in the endoplasmic reticulum using C-terminus KDEL sequence. The coding sequences were placed downstream of the rice Actin promoter and Actin-1 intron and upstream of the nopaline synthase terminator in the plant expression vectors. Transgenic wheat lines were generated through micro projectile bombardment of immature embryos of spring wheat cultivar Seri 82. Levels of antifreeze protein in the transgenic lines without any targeting peptide were low (0.06-0.07%). The apoplast-targeted protein reached a level of 1.61% of total soluble protein, 90% of which was present in the apoplast. ER-retained protein accumulated in the cells at levels up to 0.65% of total soluble proteins. Transgenic wheat line T-8 with apoplast-targeted antifreeze protein exhibited the highest levels of antifreeze activity and provided significant freezing protection even at temperatures as low as -7 degrees C.

  2. Synthetic peptides for antibody production

    NARCIS (Netherlands)

    Zegers, N.D.

    1995-01-01

    Synthetic peptides are useful tools for the generation of antibodies. The use of antibodies as specific reagents in inununochemical assays is widely applied. In this chapter, the application of synthetic peptides for the generation of antibodies is described. The different steps that lead to the

  3. Selectivity in Ligand Binding to Uranyl Compounds: A Synthetic, Structural, Thermodynamic and Computational Study

    Energy Technology Data Exchange (ETDEWEB)

    Arnold, John [Univ. of California, Berkeley, CA (United States)

    2017-12-06

    The uranyl cation (UO22+) is the most abundant form of uranium on the planet. It is estimated that 4.5 billion tons of uranium in this form exist in sea water. The ability to bind and extract the uranyl cation from aqueous solution while separating it from other elements would provide a limitless source of nuclear fuel. A large body of research concerns the selective recognition and extraction of uranyl. A stable molecule, the cation has a linear O=U=O geometry. The short U-O bonds (1.78 Å) arise from the combination of uranium 5f/6d and oxygen 2p orbitals. Due to the oxygen moieties being multiply bonded, these sites were not thought to be basic enough for Lewis acidic coordination to be a viable approach to sequestration. We believe that the goal of developing a practical system for uranium separation from seawater will not be attained without new insights into our existing fundamental knowledge of actinide chemistry. We posit that detailed studies of the kinetic and thermodynamic factors that influence interactions between f-elements and ligands with a range of donor atoms is essential to any major advance in this important area. The goal of this research is thus to broaden the coordination chemistry of the uranyl ion by studying new ligand systems via synthetic, structural, thermodynamic and computational methods. We anticipate that this fundamental science will find use beyond actinide separation technologies in areas such as nuclear waste remediation and nuclear materials.

  4. Fate of conjugated natural and synthetic steroid estrogens in crude sewage and activated sludge batch studies.

    Science.gov (United States)

    Gomes, Rachel L; Scrimshaw, Mark D; Lester, John N

    2009-05-15

    Steroids are excreted from the human body in the conjugated form but are present in sewage influent and effluent as the free steroid, the major source of estrogenic activity observed in water courses. The fate of sulfate and glucuronide conjugated steroid estrogens was investigated in batch studies using activated sludge grown on synthetic sewage in a laboratory-scale Husmann simulation and crude sewage from the field. A clear distinction between the fate of sulfate and glucuronide conjugates was observed in both matrices, with sulfated conjugates proving more recalcitrant and glucuronide deconjugation preferential in crude sewage. For each conjugate, the free steroid was observed in the biotic samples. The degree of free steroid formation was dependent on the conjugate moiety, favoring the glucuronide. Subsequent degradation of the free steroid (and sorption to the activated sludge solid phase) was evaluated. Deconjugation followed the first order reaction rate with rate constants for 17alpha-ethinylestradiol 3-glucuronide, estriol l6alpha-glucuronide, and estrone 3-glucuronide determined as 0.32, 0.24, and 0.35 h respectively. The activated sludge solid retention time over the range of 3-9 days had 74 to 94% of sulfate conjugates remaining after 8 h. In contrast, a correlation between increasing temperature and decreasing 17alpha-ethinylestradiol 3-glucuronide concentrations in the activated sludge observed no conjugate present in the AS following 8 h at 22 degrees C Based on these batch studies and literature excretion profiles, a hypothesis is presented on which steroids and what form (glucuronide, sulfate, or free) will likely enter the sewage treatment plant.

  5. Synthetic environments

    Science.gov (United States)

    Lukes, George E.; Cain, Joel M.

    1996-02-01

    The Advanced Distributed Simulation (ADS) Synthetic Environments Program seeks to create robust virtual worlds from operational terrain and environmental data sources of sufficient fidelity and currency to interact with the real world. While some applications can be met by direct exploitation of standard digital terrain data, more demanding applications -- particularly those support operations 'close to the ground' -- are well-served by emerging capabilities for 'value-adding' by the user working with controlled imagery. For users to rigorously refine and exploit controlled imagery within functionally different workstations they must have a shared framework to allow interoperability within and between these environments in terms of passing image and object coordinates and other information using a variety of validated sensor models. The Synthetic Environments Program is now being expanded to address rapid construction of virtual worlds with research initiatives in digital mapping, softcopy workstations, and cartographic image understanding. The Synthetic Environments Program is also participating in a joint initiative for a sensor model applications programer's interface (API) to ensure that a common controlled imagery exploitation framework is available to all researchers, developers and users. This presentation provides an introduction to ADS and the associated requirements for synthetic environments to support synthetic theaters of war. It provides a technical rationale for exploring applications of image understanding technology to automated cartography in support of ADS and related programs benefitting from automated analysis of mapping, earth resources and reconnaissance imagery. And it provides an overview and status of the joint initiative for a sensor model API.

  6. An atlas of November 1978 synthetic aperture radar digitized imagery for oil spill studies

    Science.gov (United States)

    Maurer, H. E.; Oderman, W.; Crosswell, W. F.

    1982-01-01

    A data set is described which consists of digitized synthetic aperture radar (SAR) imagery plus correlative data and some preliminary analysis results. This data set should be of value to experimenters who are interested in the SAR instrument and its application to the detection and monitoring of oil on water and other distributed targets.

  7. What can science and technology studies learn from art and design? Reflections on 'Synthetic Aesthetics'.

    Science.gov (United States)

    Calvert, Jane; Schyfter, Pablo

    2017-04-01

    In this paper we reflect on a project called 'Synthetic Aesthetics', which brought together synthetic biologists with artists and designers in paired exchanges. We - the STS researchers on the project - were quickly struck by the similarities between our objectives and those of the artists and designers. We shared interests in forging new collaborations with synthetic biologists, 'opening up' the science by exploring implicit assumptions, and interrogating dominant research agendas. But there were also differences between us, the most important being that the artists and designers made tangible artefacts, which had an immediacy and an ability to travel, and which seemed to allow different types of discussions from those initiated by our academic texts. The artists and designers also appeared to have the freedom to be more playful, challenging and perhaps subversive in their interactions with synthetic biology. In this paper we reflect on what we learned from working with the artists and designers on the project, and we argue that engaging more closely with art and design can enrich STS work by enabling an emergent form of critique.

  8. Heating stage Raman and infrared emission spectroscopic study of the dehydroxylation of synthetic Mg-hydrotalcite

    International Nuclear Information System (INIS)

    Kloprogge, J.T.; Hickey, L.; Frost, R.L.

    1998-01-01

    Full text: Hydrotalcites, also described as anionic clays or layered double hydroxides (LDH), form an important group of compounds because of their catalytic (basic) activity, as a precursor for the preparation of oxidic catalysts as for other specific powder properties such as filler, UV-radiation stabiliser, chloride scavenger and thermal stabiliser (Titulaer, 1993). The structure of hydrotalcites can be visualised as positively charged hydroxide layers comparable to the hydroxide layers in brucite, Mg(OH) 2 , in which a part of the divalent metal is substituted by a trivalent metal separated by charge compensating mostly hydrated anions in a so-called interlayer between the hydroxide layers. In both naturally occurring and synthetic hydrotalcites a broad range of compositions are possible of the type [M 2+ 1-x M 3+ x (OH) 2 ][A n- ] x/n. yH 2 O, where M 2+ and M 3+ are the di- and trivalent cations in the octahedral positions within the hydroxide layers with x normally between 0.17 and 0.33. A n- is an exchangeable interlayer anion. The thermal behaviour of hydrotalcites is of importance for a number of applications indicated above. For example, when a hydrotalcite is used as a precursor for the preparation of mixed metal oxide catalysts the dehydration, decarbonisation and dehydroxylation reactions must be well known in order to control the final reaction product. The hydrotalcite Mg 6 Al 2 (OH) 16 CO 3 .nH 2 O was synthesised according to the method described before by Kloprogge and Frost (1999a,b). This method comprises the slow simultaneous addition of a mixed aluminium nitrate (0.25M)-magnesium nitrate (0.75M), aluminium nitrate (0.25M)-solutions and a mixed NaOH (2.00M)-Na 2 CO 3 (0.125M) solution under vigorous stirring buffering the pH at approximately 10. The product was washed to eliminate excess salt and dried at 60 deg C. The thermal behaviour of synthetic hydrotalcite, Mg 6 Al 2 (OH)O 16 CO 3 .nH 2 O, has been studied by Infrared Emission

  9. Pilot study on peptide purity—synthetic human C-peptide

    Science.gov (United States)

    Josephs, R. D.; Li, M.; Song, D.; Daireaux, A.; Choteau, T.; Stoppacher, N.; Westwood, S.; Wielgosz, R.; Xiao, P.; Liu, Y.; Gao, X.; Zhang, C.; Zhang, T.; Mi, W.; Quan, C.; Huang, T.; Li, H.; Melanson, J. E.; Ün, I.; Gören, A. C.; Quaglia, M.; Warren, J.

    2017-01-01

    Under the auspices of the Protein Analysis Working Group (PAWG) of the Comité Consultatif pour la Quantité de Matière (CCQM) a pilot study, CCQM-P55.2, was coordinated by the Bureau International des Poids et Mesures (BIPM) and the Chinese National Institute of Metrology (NIM). Four Metrology Institutes or Designated Institutes and the BIPM participated. Participants were required to assign the mass fraction of human C-peptide (hCP) present as the main component in the comparison sample for CCQM-P55.2. The comparison samples were prepared from synthetic human hCP purchased from a commercial supplier and used as provided without further treatment or purification. hCP was selected to be representative of the performance of a laboratory's measurement capability for the purity assignment of short (up to 5 kDa), non-cross-linked synthetic peptides/proteins. It was anticipated to provide an analytical measurement challenge representative for the value-assignment of compounds of broadly similar structural characteristics. The majority of participants used a quantitative nuclear magnetic resonance spectroscopy (qNMR) corrected for peptide impurities. Other participants provided results obtained by peptide impurity corrected amino acid analysis (PICAA) or elemental analysis (PICCHN). It was decided to assign reference values based on the KCRVs of CCQM-K115 for both the hCP mass fraction and the mass fraction of the peptide related impurities as indispensable contributor regardless of the use of PICAA, mass balance or any other approach to determine the hCP purity. This allowed participants to demonstrate the efficacy of their implementation of the approaches used to determine the hCP mass fraction. In particular it allows participants to demonstrate the efficacy of their implementation of peptide related impurity identification and quantification. The assessment of the mass fraction of peptide impurities is based on the assumption that only the most exhaustive and

  10. Rubidium-strontium and uranium-lead isotopic age studies

    International Nuclear Information System (INIS)

    Loveridge, W.D.

    1981-01-01

    The results of five Rb-Sr isotopic age studies predominantly on whole-rock samples, and six U-Pb studies on zircon monazite concentrates are presented. Descriptions of the geological problems and interpretations of the measured ages are included. Laboratory age determination methods and techniques are described or referenced

  11. Longitudinal study of habits leading to malocclusion development in childhood

    OpenAIRE

    Moimaz, Suzely Adas Saliba; Garbin, Artênio José Ísper; Lima, Arinilson Moreira Chaves; Lolli, Luiz Fernando; Saliba, Orlando; Garbin, Cléa Adas Saliba

    2014-01-01

    Background: The increased prevalence of malocclusions represents a secular trend attributed to the interaction of genetic and environmental factors. The analysis of factors related to the causes of these changes is essential for planning public health policies aimed at preventing and clinically intercepting malocclusion. This study investigated the sucking habits, nocturnal mouth breathing, as well as the relation of these factors with malocclusion.Methods: This is a longitudinal study in whi...

  12. New Synthetic Methods for Hypericum Natural Products

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Insik [Iowa State Univ., Ames, IA (United States)

    2006-01-01

    Organic chemistry has served as a solid foundation for interdisciplinary research areas, such as molecular biology and medicinal chemistry. An understanding of the biological activities and structural elucidations of natural products can lead to the development of clinically valuable therapeutic options. The advancements of modern synthetic methodologies allow for more elaborate and concise natural product syntheses. The theme of this study centers on the synthesis of natural products with particularly challenging structures and interesting biological activities. The synthetic expertise developed here will be applicable to analog syntheses and to other research problems.

  13. International Study Transitions: Creating and Leading a Reentry Workshop.

    Science.gov (United States)

    Lerstrom, Alan C.

    Many American colleges and universities have developed successful programs to help prepare students for the culture shock associated with living and studying overseas, but have been less effective in aiding students as they return home and experience "reverse culture shock" or the problems associated with reentry. Culture and reentry…

  14. KINETIC STUDIES ON THE SORPTION OF LEAD AND CADMIUM ...

    African Journals Online (AJOL)

    Kinetic investigations are necessary for determining the rate of reaction and mechanism. The kinetics of the sorption of Pb2+ and Cd2+ from aqueous solution on to the biomass of C. bicolor was studied by batch equilibrium technique. The removal of the two metal ions was found to be > 60% depending on the initial metal ...

  15. Synthetic Rutile

    International Nuclear Information System (INIS)

    Burastero, J.

    1975-01-01

    This work is about the laboratory scale investigation of the conditions in the rutile synthetic production from one me nita in Aguas Dulces reservoir. The iron mineral is chlorinated and volatilized selectively leaving a residue enriched in titanium dioxide which can be used as a substitute of rutile mineral

  16. Longitudinal study of habits leading to malocclusion development in childhood.

    Science.gov (United States)

    Moimaz, Suzely Adas Saliba; Garbin, Artênio José Ísper; Lima, Arinilson Moreira Chaves; Lolli, Luiz Fernando; Saliba, Orlando; Garbin, Cléa Adas Saliba

    2014-08-04

    The increased prevalence of malocclusions represents a secular trend attributed to the interaction of genetic and environmental factors. The analysis of factors related to the causes of these changes is essential for planning public health policies aimed at preventing and clinically intercepting malocclusion. This study investigated the sucking habits, nocturnal mouth breathing, as well as the relation of these factors with malocclusion. This is a longitudinal study in which 80 mother-child pairs were monitored from the beginning of pregnancy to the 30th month after childbirth. Home visits for interviews with the mothers were made on the 12th, 18th and 30th months of age. Finger sucking, pacifier sucking, bottle feeding, breastfeeding and nocturnal mouth breathing, were the variables studies. On the 30th month, clinical examinations were performed for overjet, overbite and posterior crossbite. A previously calibrated single examiner (Kappa coefficient = 0.92) was responsible for all examinations. Data were analyzed using the chi-squared or Fisher's exact tests, at a significance level of 5%. Bottle feeding was the most prevalent habit at 12, 18 and 30 months (87.5%; 90% and 96.25%, respectively). Breastfeeding was 40%, 25% and 12.50% at 12, 18 and 30 months, respectively. Nearly 70% of the children in this study had some sort of malocclusion. Pacifier sucking habit at 12, 18 and 30 months of age was associated with overjet and open bite; and at 30 months, an association with overbite was also observed. Finger sucking habit and breastfeeding at 12, 18 and 30 months were also associated with overjet and open bite. The posterior crossbite was associated with bottle feeding at 12 and 30 months, and nocturnal mouth breathers at 12 and 18 months. Sucking habits, low rates of breastfeeding, and nocturnal mouth breathing were risk factors for malocclusion.

  17. Longitudinal study of habits leading to malocclusion development in childhood

    Science.gov (United States)

    2014-01-01

    Background The increased prevalence of malocclusions represents a secular trend attributed to the interaction of genetic and environmental factors. The analysis of factors related to the causes of these changes is essential for planning public health policies aimed at preventing and clinically intercepting malocclusion. This study investigated the sucking habits, nocturnal mouth breathing, as well as the relation of these factors with malocclusion. Methods This is a longitudinal study in which 80 mother-child pairs were monitored from the beginning of pregnancy to the 30th month after childbirth. Home visits for interviews with the mothers were made on the 12th, 18th and 30th months of age. Finger sucking, pacifier sucking, bottle feeding, breastfeeding and nocturnal mouth breathing, were the variables studies. On the 30th month, clinical examinations were performed for overjet, overbite and posterior crossbite. A previously calibrated single examiner (Kappa coefficient = 0.92) was responsible for all examinations. Data were analyzed using the chi-squared or Fisher’s exact tests, at a significance level of 5%. Results Bottle feeding was the most prevalent habit at 12, 18 and 30 months (87.5%; 90% and 96.25%, respectively). Breastfeeding was 40%, 25% and 12.50% at 12, 18 and 30 months, respectively. Nearly 70% of the children in this study had some sort of malocclusion. Pacifier sucking habit at 12, 18 and 30 months of age was associated with overjet and open bite; and at 30 months, an association with overbite was also observed. Finger sucking habit and breastfeeding at 12, 18 and 30 months were also associated with overjet and open bite. The posterior crossbite was associated with bottle feeding at 12 and 30 months, and nocturnal mouth breathers at 12 and 18 months. Conclusions Sucking habits, low rates of breastfeeding, and nocturnal mouth breathing were risk factors for malocclusion. PMID:25091288

  18. Synthetic seed production and physio-biochemical studies in Cassia angustifolia Vahl. - a medicinal plant.

    Science.gov (United States)

    Bukhari, N A W; Siddique, Iram; Perveen, K; Siddiqui, I; Alwahibi, M S

    2014-09-01

    Synthetic seed technology is an alternative to traditional micropropagation for production and delivery of cloned plantlets. Synthetic seeds were produced by encapsulating nodal segments of C. angustifolia in calcium alginate gel. 3% (w/v) sodium alginate and 100 mM CaCl2 · 2H2O were found most suitable for encapsulation of nodal segments. Synthetic seeds cultured on half strength Murashige and Skoog medium supplemented with thidiazuron (5.0 μM) + indole-3-acetic acid (1.0 μM) produced maximum number of shoots (10.9 ± 0.78) after 8 weeks of culture exhibiting (78%) in vitro conversion response. Encapsulated nodal segments demonstrated successful regeneration after different period (1-6 weeks) of cold storage at 4 °C. The synthetic seeds stored at 4 °C for a period of 4 weeks resulted in maximum conversion frequency (93%) after 8 weeks when placed back to regeneration medium. The isolated shoots when cultured on half strength Murashige and Skoog medium supplemented with 1.0 μM indole-3-butyric acid (IBA), produced healthy roots and plantlets with well-developed shoot and roots were successfully hardened off in plastic pots containing sterile soilrite inside the growth chamber and gradually transferred to greenhouse where they grew well with 85% survival rate. Growth performance of 2 months old in vitro-raised plant was compared with in vivo seedlings of the same age. Changes in the content of photosynthetic pigments, net photosynthetic rate (PN), superoxide dismutase and catalase activity in C. angustifolia indicated the adaptation of micropropagated plants to ex vitro conditions.

  19. Synthetic Glucocorticoids and Early Variations of Blood Pressure: A Population-Based Cohort Study.

    Science.gov (United States)

    Fardet, Laurence; Nazareth, Irwin; Petersen, Irene

    2015-07-01

    Endogenous glucocorticoids are known to increase blood pressure, but very little is known about the early effects of synthetic glucocorticoids (eg, prednisone, dexamethasone) on blood pressure. To assess longitudinal variations of blood pressure before and after initiation of systemic glucocorticoid therapy. Adult patients prescribed synthetic glucocorticoid therapy for at least 3 months and registered between 2004 and 2012 in The Health Improvement Network (THIN) primary care database. Systolic and diastolic blood pressure as measured in primary care. Among the 16,351 patients prescribed antihypertensive drug within the year before glucocorticoid initiation (women, 57.1%; age [mean ± SD], 72.0 ± 11.4 y), the mean (SD) blood pressure within the year before glucocorticoid initiation was 140 (18)/78 (9) mm Hg. It was 139 (19)/77 (11), 139 (19)/77 (10), and 139 (19)/77 (11) mm Hg during the first, second, and third months of exposure, respectively. We did not find any evidence of the effects of glucocorticoids on blood pressure in these patients. Among the 6914 patients not prescribed antihypertensive drug within the year before glucocorticoid initiation (women, 64.9%; age, 60.0 ± 17.8 y), the figures were 133 (17)/78 (10), 135 (20)/79 (11), 133 (19)/78 (11), and 133 (19)/78 (11) mm Hg before exposure and during the first, second, and third months of exposure, respectively. In this group of patients, glucocorticoid exposure was associated with a slight (glucocorticoid initiation. Prednisone/prednisolone use was associated with a higher risk of extreme increase in systolic blood pressure than the other synthetic glucocorticoids (odds ratio, 4.9 [95% confidence interval, 1.9-12.6]; P = .001). Contrary to what is usually thought, the increase of blood pressure during the first months of exposure to synthetic glucocorticoids seems clinically nonsignificant.

  20. High-pressure optical spectroscopy and X-ray diffraction studies on synthetic cobalt aluminum silicate garnet

    DEFF Research Database (Denmark)

    N. Taran, Michail; Nestola, Fabrizio; Ohashi, Haruo

    2007-01-01

    The pressure-induced behavior of spin-allowed dd-bands of VIIICo2+ in the absorption spectra of synthetic Co3Al2Si3O12 garnet was studied from 10-4 to 13 GPa. The plots of the peak energy vs. pressure for the three sharpest well resolved bands at ca. 5160, 17 680, and 18 740 cm-1 display small bu...

  1. CUSTOMER PERCEIVED QUALITY IMPROVEMENT OF SYNTHETIC FIBER USING FUZZY QFD: A CASE STUDY

    Directory of Open Access Journals (Sweden)

    Golam Kabir

    2011-06-01

    Full Text Available The performance of the ready-made garment (RMG industry has been one of the most notable success stories of the Bangladesh economy over two decades. To meet the growing demand of synthetic yarns, Bangladesh has to import it from foreign countries which cost a substantial amount of foreign currency for the country. It is a pressing need for local manufacturers to come forward, produce quality synthetic yarn and fulfill the demand of the local market. The purpose of this paper is to present a Fuzzy Quality Function Deployment (FQFD model to indentify customer requirements and also demonstrate how these requirements can be used to prioritize the design requirements for manufacturing of synthetic yarns. In this system, Fuzzy set theory is integrated into house of quality (HOQ to overcome the shortcomings of the traditional QFD and to capture the inherent impreciseness and vagueness of customer requirements and facilitate to prioritize QFD information. Improving high priority design requirements will ultimately increase customer satisfaction and as a result customer perceived quality will soar.

  2. Results of Parametric Design Studies of MOX Lead Test Assembly

    Energy Technology Data Exchange (ETDEWEB)

    Pavlovitchev, A.M.; Bychkov, S.A.; Lazarenko, A.A.; Sidorenko, V.D.; Styrin, Y.A.

    1998-12-01

    The parametric studies of MOX LTA design have been executed to choose plutonium content in assembly zones for two options of MOX LTA: 3-zones and Island. For 3-zones (100% Plutonium) MOX LTA the fissile plutonium content composition of 4.2%/3,0%/2% has been chosen. MOX LTA of the chosen compositions has been studied by using multi-assembly configuration that allows investigating of influence of MOX LTA environment: uranium assemblies of different irradiation. Plutonium Island with 54 plutonium pins in the center of MOX LTA has been considered in two modifications: uniform island; and graded island with lower plutonium content in one peripheral row of pins. It is shown that plutonium content in the uniform island cannot exceed 2.7% because of adopted power peaking limitations and therefore this design seems unreasonable for practical use. For graded island the plutonium content composition 3.8%/2.8% with uranium environment of 3.7% U-235 has been chosen. Evolution of assembly power and burnup distributions, inter-pin power and isotopic distributions while fuel irradiating have been analyzed. In addition to the base uranium environment of 3.7%, a set of calculations has been executed for 4.4%. Most of the studies have been executed by the code TVS-M that is at the final stage of licensing and it is to be used in the nearest future as a base instrument for VVER core calculations while using both uranium and MOX fuel. So the obtained results must be considered as preliminary ones and they demand additional analysis and investigations.

  3. Results of Parametric Design Studies of MOX Lead Test Assembly

    International Nuclear Information System (INIS)

    Pavlovitchev, A.M.; Bychkov, S.A.; Lazarenko, A.A.; Sidorenko, V.D.; Styrin, Y.A.

    1998-01-01

    The parametric studies of MOX LTA design have been executed to choose plutonium content in assembly zones for two options of MOX LTA: 3-zones and Island. For 3-zones (100% Plutonium) MOX LTA the fissile plutonium content composition of 4.2%/3,0%/2% has been chosen. MOX LTA of the chosen compositions has been studied by using multi-assembly configuration that allows investigating of influence of MOX LTA environment: uranium assemblies of different irradiation. Plutonium Island with 54 plutonium pins in the center of MOX LTA has been considered in two modifications: uniform island; and graded island with lower plutonium content in one peripheral row of pins. It is shown that plutonium content in the uniform island cannot exceed 2.7% because of adopted power peaking limitations and therefore this design seems unreasonable for practical use. For graded island the plutonium content composition 3.8%/2.8% with uranium environment of 3.7% U-235 has been chosen. Evolution of assembly power and burnup distributions, inter-pin power and isotopic distributions while fuel irradiating have been analyzed. In addition to the base uranium environment of 3.7%, a set of calculations has been executed for 4.4%. Most of the studies have been executed by the code TVS-M that is at the final stage of licensing and it is to be used in the nearest future as a base instrument for VVER core calculations while using both uranium and MOX fuel. So the obtained results must be considered as preliminary ones and they demand additional analysis and investigations

  4. Leading teams during simulated pediatric emergencies: a pilot study.

    Science.gov (United States)

    Coolen, Ester H; Draaisma, Jos M; den Hamer, Sabien; Loeffen, Jan L

    2015-01-01

    Leadership has been identified as a key variable for the functioning of teams and as one of the main reasons for success or failure of team-based work systems. Pediatricians often function as team leaders in the resuscitation of a critically ill child. However, pediatric residents often report having little opportunity to perform in the role of team leader during residency. In order to gain more insight into leadership skills and behaviors, we classified leadership styles of pediatric residents during simulated emergencies. We conducted a prospective quantitative study to investigate leadership styles used by pediatric residents during simulated emergencies with clinical deterioration of a child at a pediatric ward. Using videotaped scenarios of 48 simulated critical events among 12 residents, we were able to classify verbal and nonverbal communication into different leadership styles according to the situational leadership theory. The coaching style (mean 54.5%, SD 7.8) is the most frequently applied by residents, followed by the directing style (mean 35.6%, SD 4.1). This pattern conforms to the task- and role-related requirements in our scenarios and it also conforms to the concept of situational leadership. We did not find any significant differences in leadership style according to the postgraduate year or scenario content. The model used in this pilot study helps us to gain a better understanding of the development of effective leadership behavior and supports the applicability of situational leadership theory in training leadership skills during residency.

  5. Leading teams during simulated pediatric emergencies: a pilot study

    Science.gov (United States)

    Coolen, Ester H; Draaisma, Jos M; den Hamer, Sabien; Loeffen, Jan L

    2015-01-01

    Purpose Leadership has been identified as a key variable for the functioning of teams and as one of the main reasons for success or failure of team-based work systems. Pediatricians often function as team leaders in the resuscitation of a critically ill child. However, pediatric residents often report having little opportunity to perform in the role of team leader during residency. In order to gain more insight into leadership skills and behaviors, we classified leadership styles of pediatric residents during simulated emergencies. Methods We conducted a prospective quantitative study to investigate leadership styles used by pediatric residents during simulated emergencies with clinical deterioration of a child at a pediatric ward. Using videotaped scenarios of 48 simulated critical events among 12 residents, we were able to classify verbal and nonverbal communication into different leadership styles according to the situational leadership theory. Results The coaching style (mean 54.5%, SD 7.8) is the most frequently applied by residents, followed by the directing style (mean 35.6%, SD 4.1). This pattern conforms to the task- and role-related requirements in our scenarios and it also conforms to the concept of situational leadership. We did not find any significant differences in leadership style according to the postgraduate year or scenario content. Conclusion The model used in this pilot study helps us to gain a better understanding of the development of effective leadership behavior and supports the applicability of situational leadership theory in training leadership skills during residency. PMID:25610010

  6. Leading teams during simulated pediatric emergencies: a pilot study

    Directory of Open Access Journals (Sweden)

    Coolen EH

    2015-01-01

    Full Text Available Ester H Coolen,1 Jos M Draaisma,2 Sabien den Hamer,3 Jan L Loeffen2 1Department of Pediatric Surgery, Amalia Children’s Hospital, Radboud University Medical Center, 2Department of Pediatrics, Amalia Children’s Hospital, Radboud University Medical Center, 3Department of Communication Science, Radboud University, Nijmegen, the Netherlands Purpose: Leadership has been identified as a key variable for the functioning of teams and as one of the main reasons for success or failure of team-based work systems. Pediatricians often function as team leaders in the resuscitation of a critically ill child. However, pediatric residents often report having little opportunity to perform in the role of team leader during residency. In order to gain more insight into leadership skills and behaviors, we classified leadership styles of pediatric residents during simulated emergencies. Methods: We conducted a prospective quantitative study to investigate leadership styles used by pediatric residents during simulated emergencies with clinical deterioration of a child at a pediatric ward. Using videotaped scenarios of 48 simulated critical events among 12 residents, we were able to classify verbal and nonverbal communication into different leadership styles according to the situational leadership theory. Results: The coaching style (mean 54.5%, SD 7.8 is the most frequently applied by residents, followed by the directing style (mean 35.6%, SD 4.1. This pattern conforms to the task- and role-related requirements in our scenarios and it also conforms to the concept of situational leadership. We did not find any significant differences in leadership style according to the postgraduate year or scenario content. Conclusion: The model used in this pilot study helps us to gain a better understanding of the development of effective leadership behavior and supports the applicability of situational leadership theory in training leadership skills during residency. Keywords

  7. Experimental and quantum chemical studies of a novel synthetic prenylated chalcone

    Directory of Open Access Journals (Sweden)

    Espinoza-Hicks José C

    2013-01-01

    Full Text Available Abstract Background Chalcones are ubiquitous natural compounds with a wide variety of reported biological activities, including antitumoral, antiviral and antimicrobial effects. Furthermore, chalcones are being studied for its potential use in organic electroluminescent devices; therefore the description of their spectroscopic properties is important to elucidate the structure of these molecules. One of the main techniques available for structure elucidation is the use of Nuclear Magnetic Resonance Spectroscopy (NMR. Accordingly, the prediction of the NMR spectra in this kind of molecules is necessary to gather information about the influence of substituents on their spectra. Results A novel substituted chalcone has been synthetized. In order to identify the functional groups present in the new synthesized compound and confirm its chemical structure, experimental and theoretical 1H-NMR and 13C-NMR spectra were analyzed. The theoretical molecular structure and NMR spectra were calculated at both the Hartree-Fock and Density Functional (meta: TPSS; hybrid: B3LYP and PBE1PBE; hybrid meta GGA: M05-2X and M06-2X levels of theory in combination with a 6-311++G(d,p basis set. The structural parameters showed that the best method for geometry optimization was DFT:M06-2X/6-311++G(d,p, whereas the calculated bond angles and bond distances match experimental values of similar chalcone derivatives. The NMR calculations were carried out using the Gauge-Independent Atomic Orbital (GIAO formalism in a DFT:M06-2X/6-311++G(d,p optimized geometry. Conclusion Considering all HF and DFT methods with GIAO calculations, TPSS and PBE1PBE were the most accurate methods used for calculation of 1H-NMR and 13C-NMR chemical shifts, which was almost similar to the B3LYP functional, followed in order by HF, M05-2X and M06-2X methods. All calculations were done using the Gaussian 09 software package. Theoretical calculations can be used to predict and confirm the structure of

  8. Spectroscopic study of neodymium doped lead-bismuth-borate glasses

    Energy Technology Data Exchange (ETDEWEB)

    Pasha, Altaf; Dayani, P.; Negalur, Mahesh; Swamy, Manjunatha; Abhiram, J. [Dept of Post Graduate Studies & Research in Physics, The National Degree College, Bangalore (India); Rajaramakrishna, R. [Dept of Post Graduate Studies & Research in Physics, The National Degree College, Bangalore (India); Physics Department, Bangalore University, Bangalore (India)

    2016-05-06

    This paper reports on different physical and optical properties of rare earth doped heavy metal oxide glasses. The glass composition of 10Bi{sub 2}O{sub 3}-30PbO-60B{sub 2}O{sub 3}-xNd{sub 2}O{sub 3} where x = 0, 0.1, 0.2, 0.5 and 1 (in mol %) has been synthesized using melt-quenching technique. Refractive index measurements for these glasses were done and physical parameters were studied. Structural properties of these glasses were analysed through infrared spectra that was recorded between 1600cm{sup −1} and 300cm{sup −1} in transmission mode. The optical absorption spectra were recorded in the wavelength range from 300 to 700 nm. The transitions originated from ground state energy {sup 4}I{sub 9/2}. The energy level analysis has been carried out by considering absorption spectral bands. The results thus obtained are comparable with reports on similar glasses, indicating that the prepared glasses may have potential laser applications.

  9. Micron SR Studies of High Critical Temperature Superconductor Lead

    Science.gov (United States)

    Wu, Wei-Dong

    1995-01-01

    Flux depinning phenomena in the rm Bi_2Sr_2CaCu_2O_8 (Bi2212) and rm Pb_{0.7}Bi_ {1.3}Sr_2CaCu_2O_8 (Pb-Bi2212) systems have been studied using the technique of transverse field (TF) muSR. Comparison of field-cooled (FC) and zero-field-cooled (ZFC) results defines an irreversibility (depinning) temperature T _{rm irr}: the ZFC and FC relaxation rates are essentially identical above T _{rm irr}, while the ZFC relaxation rate is larger than the FC relaxation rate below T_{rm irr}, reflecting the increased inhomogeneity of the local fields in the ZFC measurements due to flux pinning. The irreversibility line T_{irr}(H) of Bi2212 obtained by muSR measurements is compared with those from dc and ac-susceptibility, and mechanical oscillator measurements. I show that the results from muSR and these other techniques can be explained consistently within a framework of the flux creep model. The irreversibility temperature in Pb -Bi2212, determined by muSR measurements, is significantly higher than that in the pure Bi2212 system. This result, together with the larger critical current and the higher activation energy U_0 in the Pb-Bi2212 crystals as found by the dc-susceptibility measurements, suggests an enhancement of flux pinning by the Pb doping. In order to fit the muSR asymmetry measured in Y_{1-x} U_{x}Pd _3, I have performed Monte Carlo simulations for spin glasses with impurity concentration x between 0 and 1; I found that the stretched exponential decay of muon polarisation found empirically in many spin glasses above the spin freezing temperature T_{g } is consistent with a lognormal distribution of the fluctuation rate nu. Our muSR measurements of Y_ {1-x}U_{x}Pd _3 and UPd_4 demonstrate the disappearance of magnetic order with decreasing U concentration x with a threshold U concentration x _{rm th} ~ 0.2. I show that the behavior is consistent with Sherrington's induced spin glass model based on the competition between exchange interaction coupling {cal T } and the

  10. Key comparison study on peptide purity—synthetic human C-peptide

    Science.gov (United States)

    Josephs, R. D.; Li, M.; Song, D.; Westwood, S.; Stoppacher, N.; Daireaux, A.; Choteau, T.; Wielgosz, R.; Xiao, P.; Liu, Y.; Gao, X.; Zhang, C.; Zhang, T.; Mi, W.; Quan, C.; Huang, T.; Li, H.; Flatschart, R.; Borges Oliveira, R.; Melanson, J. E.; Ohlendorf, R.; Henrion, A.; Kinumi, T.; Wong, L.; Liu, Q.; Oztug Senal, M.; Vatansever, B.; Ün, I.; Gören, A. C.; Akgöz, M.; Quaglia, M.; Warren, J.

    2017-01-01

    Under the auspices of the Protein Analysis Working Group (PAWG) of the Comité Consultatif pour la Quantité de Matière (CCQM) a key comparison, CCQM-K115, was coordinated by the Bureau International des Poids et Mesures (BIPM) and the Chinese National Institute of Metrology (NIM). Eight Metrology Institutes or Designated Institutes and the BIPM participated. Participants were required to assign the mass fraction of human C-peptide (hCP) present as the main component in the comparison sample for CCQM-K115. The comparison samples were prepared from synthetic human hCP purchased from a commercial supplier and used as provided without further treatment or purification. hCP was selected to be representative of the performance of a laboratory's measurement capability for the purity assignment of short (up to 5 kDa), non-cross-linked synthetic peptides/proteins. It was anticipated to provide an analytical measurement challenge representative for the value-assignment of compounds of broadly similar structural characteristics. The majority of participants used a peptide impurity corrected amino acid analysis (PICAA) approach as the amount of material that has been provided to each participant (25 mg) is insufficient to perform a full mass balance based characterization of the material by a participating laboratory. The coordinators, both the BIPM and the NIM, were the laboratories to use the mass balance approach as they had more material available. It was decided to propose KCRVs for both the hCP mass fraction and the mass fraction of the peptide related impurities as indispensable contributor regardless of the use of PICAA, mass balance or any other approach to determine the hCP purity. This allowed participants to demonstrate the efficacy of their implementation of the approaches used to determine the hCP mass fraction. In particular it allows participants to demonstrate the efficacy of their implementation of peptide related impurity identification and quantification

  11. Validated HPLC method for determination of caffeine level in human plasma using synthetic plasma: application to bioavailability studies.

    Science.gov (United States)

    Alvi, Syed N; Hammami, Muhammad M

    2011-04-01

    Several high-performance liquid chromatography (HPLC) methods have been described for the determination of caffeine in human plasma. However, none have been cross validated using synthetic plasma. The present study describes a simple and reliable HPLC method for the determination of the caffeine level in human plasma. Synthetic plasma was used to construct calibration curves and quality control samples to avoid interference by caffeine commonly present in donor's human plasma. After deproteination of plasma samples with perchloric acid, caffeine and antipyrine (internal standard, IS) were separated on a Waters Atlantis C18 column using a mobile phase of 15 mM potassium phosphate (pH 3.5) and acetonitrile (83:17, v/v), and monitored by photodiode array detector, with the wavelength set at 274 nm. The relationship between caffeine concentrations and peak area ratio (caffeine-IS) was linear over the range of 0.05-20 μg/mL. Inter-run coefficient of variation was ≤ 5.4% and ≤ 6.0% and bias was ≤ 3% and ≤ 7% using human and synthetic plasma, respectively. Mean extraction recovery from human plasma of caffeine and the IS was 91% and 86%, respectively. Caffeine in human plasma was stable for at least 24 h at room temperature or 12 weeks at -20 °C, and after three freeze-thaw cycles. The method was successfully applied to monitor caffeine levels in healthy volunteers with correction of caffeine levels using the mean ratio of the slopes of the calibration's curves constructed using human and synthetic plasma.

  12. Numerical modeling of block structure dynamics: Application to the Vrancea region and study of earthquakes sequences in the synthetic catalogs

    International Nuclear Information System (INIS)

    Soloviev, A.A.; Vorobieva, I.A.

    1995-08-01

    A seismically active region is represented as a system of absolutely rigid blocks divided by infinitely thin plane faults. The interaction of the blocks along the fault planes and with the underlying medium is viscous-elastic. The system of blocks moves as a consequence of prescribed motion of boundary blocks and the underlying medium. When for some part of a fault plane the stress surpasses a certain strength level a stress-drop (''a failure'') occurs. It can cause a failure for other parts of fault planes. The failures are considered as earthquakes. As a result of the numerical simulation a synthetic earthquake catalogue is produced. This procedure is applied for numerical modeling of dynamics of the block structure approximating the tectonic structure of the Vrancea region. By numerical experiments the values of the model parameters were obtained which supplied the synthetic earthquake catalog with the space distribution of epicenters close to the real distribution of the earthquake epicenters in the Vrancea region. The frequency-magnitude relations (Gutenberg-Richter curves) obtained for the synthetic and real catalogs have some common features. The sequences of earthquakes arising in the model are studied for some artificial structures. It is found that ''foreshocks'', ''main shocks'', and ''aftershocks'' could be detected among earthquakes forming the sequences. The features of aftershocks, foreshocks, and catalogs of main shocks are analysed. (author). 5 refs, 12 figs, 16 tabs

  13. Developmental toxicity and neurotoxicity of synthetic organic insecticides in zebrafish (Danio rerio): A comparative study of deltamethrin, acephate, and thiamethoxam.

    Science.gov (United States)

    Liu, XingYu; Zhang, QiuPing; Li, ShiBao; Mi, Ping; Chen, DongYan; Zhao, Xin; Feng, XiZeng

    2018-05-01

    Synthetic organic insecticides, including pyrethroids, organophosphates, neonicotinoids and other types, have the potential to alter the ecosystems and many are harmful to humans. This study examines the developmental toxicity and neurotoxicity of three synthetic organic insecticides, including deltamethrin (DM), acephate (AP), and thiamethoxam (TM), using embryo-larval stages of zebrafish (Danio rerio). Results showed that DM exposure led to embryo development delay and a significant increase in embryo mortality at 24 and 48 h post-fertilization (hpf). DM and AP decreased embryo chorion surface tension at 24 hpf, along with the increase in hatching rate at 72 hpf. Moreover, DM caused ntl, shh, and krox20 misexpression in a dose-dependent manner with morphological deformities of shorter body length, smaller eyes, and larger head-body angles at 10 μg/L. TM did not show significant developmental toxicity. Furthermore, results of larval rest/wake assay indicated that DM (>0.1 μg/L) and AP (0.1 mg/L) increased activity behavior with different patterns. Interestingly, as an insect-specific pesticide, TM still could alter locomotor activity in zebrafish larvae at concentrations as low as 0.1 mg/L. Our results indicate that different types of synthetic organic insecticides could create different toxicity outcomes in zebrafish embryos and larvae. Copyright © 2018 Elsevier Ltd. All rights reserved.

  14. A parametric study of rate of advance and area coverage rate performance of synthetic aperture radar.

    Energy Technology Data Exchange (ETDEWEB)

    Raynal, Ann Marie [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Hensley, Jr., William H. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Burns, Bryan L. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Doerry, Armin Walter [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)

    2014-11-01

    The linear ground distance per unit time and ground area covered per unit time of producing synthetic aperture radar (SAR) imagery, termed rate of advance (ROA) and area coverage rate (ACR), are important metrics for platform and radar performance in surveillance applications. These metrics depend on many parameters of a SAR system such as wavelength, aircraft velocity, resolution, antenna beamwidth, imaging mode, and geometry. Often the effects of these parameters on rate of advance and area coverage rate are non-linear. This report addresses the impact of different parameter spaces as they relate to rate of advance and area coverage rate performance.

  15. Monitoring of aquifer pump tests with Magnetic Resonance Sounding (MRS): a synthetic case study

    DEFF Research Database (Denmark)

    Herckenrath, Daan; Auken, E.; Bauer-Gottwein, Peter

    2011-01-01

    calculates the MRS-signal generated by an aquifer pump test. A synthetic MRS-dataset was subsequently used to determine the hydrogeological parameters in an inverse parameter estimation approach. This was done for a virtual pump test with a partially and a fully penetrating well. With the MRS data we were...... able to retrieve the hydrogeological parameters of the aquifer. However, the differences in MRS signal in time were small compared to the electromagnetic noise. This limits the applicability of the MRS technique for pump tests in which a partially penetrating pumping well is used, as the limited...

  16. Survey of Study on Internal Waves Detection in Synthetic Aperture Radar Image

    Directory of Open Access Journals (Sweden)

    Chong Jin-song

    2013-12-01

    Full Text Available In recent years, Internal Waves (IWs detection in Synthetic Aperture Radar (SAR image has received considerable attentions in the area of marine remote sensing and has already become one of the most important marine applications of SAR. Typical research results at home and abroad are reviewed. Three areas of researches are introduced and summarized, including parameter inversion method of IWs, the effect of different SAR parameter and wind field conditions on IWs imaging, the 2-dimentional SAR imaging simulation of IWs.

  17. Open questions in origin of life: experimental studies on the origin of nucleic acids and proteins with specific and functional sequences by a chemical synthetic biology approach

    DEFF Research Database (Denmark)

    Adamala, K.; Anella, F.; Wieczorek, R.

    2014-01-01

    sequences among a vast array of possible ones, the huge "sequence space", leading to the question "why these macromolecules, and not the others?" We have recently addressed these questions by using a chemical synthetic biology approach. In particular, we have tested the catalytic activity of small peptides...

  18. [Study on the soil salinization monitoring based on synthetical hyperspectral index].

    Science.gov (United States)

    Ding, Jian-Li; Wu, Man-Chun; Liu, Hai-Xia; Li, Zheng-Guang

    2012-07-01

    The present paper selected the spectral reflectivity of saline soil and vegetation of Weigan-Kuqa River Delta Oasis in the northern margin of the Tarim Basin in Xinjiang as objects, and used various spectral transforms to process the data with continum removed methods, derivate spectra, reciprocal, first order differential and root mean square etc, then analyzed the spectrum features and decided the most sensitive band ranges most relevant to salinization, and used field hyperspectral vegetation index, soil salinity index and measured synthetical spectral index to respectively establish hyperspectral quantitative models which could evaluate the soil salinization degrees. By comparing various spectral transformations of hyperspectral data the result showed that the first derivative of measured soil and vegetation hyperspectral were most sensitive to soil salinization degrees. The hyperspectral quantitative model based on measured synthetical spectral index could monitor soil salinization accurately and was better than the models simply based on vegetation index or soil salinity index. The research provided some scientific basis with soil salinization detection.

  19. Inputs and distributions of synthetic musk fragrances in an estuarine and coastal environment; a case study

    International Nuclear Information System (INIS)

    Sumner, Nicola R.; Guitart, Carlos; Fuentes, Gustavo; Readman, James W.

    2010-01-01

    Synthetic musks are ubiquitous contaminants in the environment. Compartmental distributions (dissolved, suspended particle associated and sedimentary) of the compounds throughout an axial estuarine transect and in coastal waters are reported. High concentrations of Galaxolide (HHCB) and Tonalide (AHTN) (987-2098 ng/L and 55-159 ng/L, respectively) were encountered in final effluent samples from sewage treatment plants (STPs) discharging into the Tamar and Plym Estuaries (UK), with lower concentrations of Celestolide (ADBI) (4-13 ng/L), Phantolide (AHMI) (6-9 ng/L), musk xylene (MX) (4-7 ng/L) and musk ketone (MK) (18-30 ng/L). Rapid dilution from the outfalls is demonstrated with resulting concentrations of HHCB spanning from 5 to 30 ng/L and those for AHTN from 3 to 15 ng/L. The other musks were generally not detected in the estuarine and coastal waters. The suspended particulate matter (SPM) and sedimentary profiles and compositions (HHCB:AHTN ratios) generally reflect the distribution in the water column with highest concentrations adjacent to sewage outfalls. - Synthetic musks were determined in coastal environmental compartments along an estuarine transect indicating their ubiquitous occurrence in transitional waters.

  20. A study on the C-peptide radioimmunoassay with synthetized connecting peptide

    International Nuclear Information System (INIS)

    Nakagawa, Shoichi; Sasaki, Takashi; Nakayama, Hidetaka; Watanabe, Takuji; Aoki, Shin

    1976-01-01

    A method of C-peptide radioimmunoassay with the synthetized connecting peptide by Yanaihara was tested for the determination of serum C-peptide immunoreactivity (CPR) in normal people and in diabetics with or without insulin treatment. The CPR value obtained by this method was not interfered with by the presence of serum proteins or by the insulin of people with or without insulin treatment judged by the dilution test and the recovery test. The normal fasting CPR was 2.80 +- 0.78 ng/ml with the synthetized C-peptide as a standard. The CPR value increased and reached a maximum 90 minutes after the ingestion of 50 g of glucose. The increase after the glucose loading reduced corresponding to the severity of diabetes, and some juvenile-onset diabetes showed no response. Adult-type diabetics under insulin treatment, however, showed weak but significant CPR response. The increment of CPR and immunoreactive insulin after glucose loading in normal people and non-treated diabetics was well correlated (γ=0.8262). Judged from the above mentioned results, CPR determination in insulin-treated diabetics was thought to be a useful method for the assessment of the insulin-secreting ability of beta-cells of the pancreas. (J.P.N.)

  1. Radiation damage studies on natural and synthetic rock salt utilizing measurements made during electron irradiation

    International Nuclear Information System (INIS)

    Swyler, K.J.; Levy, P.W.

    1977-01-01

    The numerous radiation damage effects which will occur in the rock salt surrounding radioactive waste disposal canisters are being investigated with unique apparatus for making optical and other measurements during 1 to 3 MeV electron irradiation. This equipment, consists of a computer controlled double beam spectrophotometer which simultaneously records 256 point absorption and radioluminescence spectra, in either the 200 to 400 or 400 to 800 nm region, every 40 seconds. Most often the measurements commence as the irradiation is started and continue after it is terminated. This procedure provides information on the kinetics and other details of the damage formation process and, when the irradiation is terminated, on both the transient and stable damage components. The exposure rates may be varied between 10 2 or 10 3 to more than 10 8 rad per hour and the sample temperature maintained between 25 and 800 or 900 0 C. Although this project was started recently, measurements have been made on synthetic NaCl and on natural rock salt from two disposal sites and two mines. Both unstrained and purposely strained samples have been used. Most recently, measurements at temperatures between 25 and 200 0 C have been started. The few measurements completed to date indicate that the damage formation kinetics in natural rock salt are quite different from those observed in synthetic NaCl

  2. Synthetic observations of molecular clouds in a galactic centre environment - I. Studying maps of column density and integrated intensity

    Science.gov (United States)

    Bertram, Erik; Glover, Simon C. O.; Clark, Paul C.; Ragan, Sarah E.; Klessen, Ralf S.

    2016-02-01

    We run numerical simulations of molecular clouds, adopting properties similar to those found in the central molecular zone (CMZ) of the Milky Way. For this, we employ the moving mesh code AREPO and perform simulations which account for a simplified treatment of time-dependent chemistry and the non-isothermal nature of gas and dust. We perform simulations using an initial density of n0 = 103 cm-3 and a mass of 1.3 × 105 M⊙. Furthermore, we vary the virial parameter, defined as the ratio of kinetic and potential energy, α = Ekin/|Epot|, by adjusting the velocity dispersion. We set it to α = 0.5, 2.0 and 8.0, in order to analyse the impact of the kinetic energy on our results. We account for the extreme conditions in the CMZ and increase both the interstellar radiation field (ISRF) and the cosmic ray flux (CRF) by a factor of 1000 compared to the values found in the solar neighbourhood. We use the radiative transfer code RADMC-3D to compute synthetic images in various diagnostic lines. These are [C II] at 158 μm, [O I] (145 μm), [O I] (63 μm), 12CO (J = 1 → 0) and 13CO (J = 1 → 0) at 2600 and 2720 μm, respectively. When α is large, the turbulence disperses much of the gas in the cloud, reducing its mean density and allowing the ISRF to penetrate more deeply into the cloud's interior. This significantly alters the chemical composition of the cloud, leading to the dissociation of a significant amount of the molecular gas. On the other hand, when α is small, the cloud remains compact, allowing more of the molecular gas to survive. We show that in each case the atomic tracers accurately reflect most of the physical properties of both the H2 and the total gas of the cloud and that they provide a useful alternative to molecular lines when studying the interstellar medium in the CMZ.

  3. Safety and effectiveness of a 6-French MRI conditional pacemaker lead: The INGEVITYTMclinical investigation study results.

    Science.gov (United States)

    Nielsen, Jens C; Giudici, Michael; Tolasana Viu, Jose Maria; Chew, Engwooi; Sommerijns, Elke; Wold, Nicholas; Evert, Linda; Love, Charles J; Stein, Kenneth; Olaf, Hedrich

    2017-10-01

    The design of pacemaker leads has continued to evolve; ease of lead handling, improved electrical performance, and magnetic resonance imaging (MRI) conditional aspects have become more important, while safety remains critical. The INGEVITY™ family leads was designed to provide MRI conditional aspects, decreased diameter, and improved performance of pacemaker leads. The INGEVITY study is an investigational device exemption trial evaluating the acute and chronic safety and effectiveness of these leads. Consecutive patients were included in 77 institutions worldwide, where 1,657 leads (846 right ventricular active fixation leads, 213 right ventricular passive fixation leads, 121 right atrial passive fixation preformed J-leads, and 477 right atrial active fixation leads) were implanted or attempted in 1,060 subjects. At 3-month follow-up, the electrical performance were: mean pacing threshold 0.67 V at 0.5-ms pulse width, pacing impedance 773 ohms, mean P-wave amplitude 4.8 mV, and R-wave amplitude 16.5 ± 6.5 mV. Over a median follow-up of 31 months, 93 subjects died and 33 subjects reported lead-related complications. Lead-related complication-free rate from 0 to 3 months and 3 to 12 months for all leads was 98.4% and 99.7%, respectively. The hazard of lead-related complications was observed to be decelerating over the course of follow-up (Weibull shape = 0.23). The overall lead dislodgment rate observed in the study was 1.3%, the perforation rate was 0.0%, and the pericardial effusion rate was 0.3%. The clinical performance of the INGEVITY lead demonstrated a high lead-related complication-free rate over 12 months of follow-up and excellent electrical characteristics. © 2017 Wiley Periodicals, Inc.

  4. Regional-scale geostatistical inverse modeling of North American CO2 fluxes: a synthetic data study

    Directory of Open Access Journals (Sweden)

    A. M. Michalak

    2010-07-01

    Full Text Available A series of synthetic data experiments is performed to investigate the ability of a regional atmospheric inversion to estimate grid-scale CO2 fluxes during the growing season over North America. The inversions are performed within a geostatistical framework without the use of any prior flux estimates or auxiliary variables, in order to focus on the atmospheric constraint provided by the nine towers collecting continuous, calibrated CO2 measurements in 2004. Using synthetic measurements and their associated concentration footprints, flux and model-data mismatch covariance parameters are first optimized, and then fluxes and their uncertainties are estimated at three different temporal resolutions. These temporal resolutions, which include a four-day average, a four-day-average diurnal cycle with 3-hourly increments, and 3-hourly fluxes, are chosen to help assess the impact of temporal aggregation errors on the estimated fluxes and covariance parameters. Estimating fluxes at a temporal resolution that can adjust the diurnal variability is found to be critical both for recovering covariance parameters directly from the atmospheric data, and for inferring accurate ecoregion-scale fluxes. Accounting for both spatial and temporal a priori covariance in the flux distribution is also found to be necessary for recovering accurate a posteriori uncertainty bounds on the estimated fluxes. Overall, the results suggest that even a fairly sparse network of 9 towers collecting continuous CO2 measurements across the continent, used with no auxiliary information or prior estimates of the flux distribution in time or space, can be used to infer relatively accurate monthly ecoregion scale CO2 surface fluxes over North America within estimated uncertainty bounds. Simulated random transport error is shown to decrease the quality of flux estimates in under-constrained areas at the ecoregion scale, although the uncertainty bounds remain realistic. While these synthetic

  5. Synthetic biology: lessons from the history of synthetic organic chemistry.

    Science.gov (United States)

    Yeh, Brian J; Lim, Wendell A

    2007-09-01

    The mid-nineteenth century saw the development of a radical new direction in chemistry: instead of simply analyzing existing molecules, chemists began to synthesize them--including molecules that did not exist in nature. The combination of this new synthetic approach with more traditional analytical approaches revolutionized chemistry, leading to a deep understanding of the fundamental principles of chemical structure and reactivity and to the emergence of the modern pharmaceutical and chemical industries. The history of synthetic chemistry offers a possible roadmap for the development and impact of synthetic biology, a nascent field in which the goal is to build novel biological systems.

  6. A study of the thermal activation of synthetic zeolites (molecular sieve) for gas-solid chromatography

    International Nuclear Information System (INIS)

    Walker, J.A.J.

    1978-10-01

    The thermal activation of synthetic zeolites from two sources has been investigated with reference to the adsorption chromatography of inorganic gases. It was found that the heats of adsorption for oxygen and carbon monoxide increased with activation temperature. Limits of detection for oxygen in argon and conversely argon in oxygen were determined as well as the chromatographic stability of the activated zeolite. The practical implications and importance of the results are discussed and the application to the analysis of fast reactor blanket gas is mentioned. An explanation is proposed for the adsorption behaviour of these activated materials, based on an electrostatic mechanism, and this has suggested a reason for the separation characteristics of oxygen and argon on polar zeolites. Further work is identified including the investigation of energy states of the oxygen molecule adsorbed on activated zeolite by means of ultra-violet photoelectron spectroscopy. (author)

  7. Studying Synthetic Polymers in the Undergraduate Chemistry Curriculum. A Review of the Educational Literature

    Science.gov (United States)

    Hodgson, Steven C.; Bigger, Stephen W.; Billingham, Norman C.

    2001-04-01

    This review and its comprehensive list of 339 references is published on the Web at the JCE Online site. It is offered as an up-to-date resource for chemical educators for their use in developing innovative ways of teaching the topic of synthetic polymers within the context of the undergraduate chemistry curriculum. An account is given of (i) the scope of polymer chemistry in education, (ii) the educational literature available in this field, (iii) course modules that may be used for instruction about polymer chemistry, and (iv) polymer-based experiments for the teaching laboratory. To encourage the wider inclusion of polymers in the undergraduate chemistry curriculum, a selection of simple experiments that relate to common polymers is recommended.

  8. Reaction Rates Of Olivine Carbonation - An Experimental Study Using Synthetic Fluid Inclusions As Micro-Reactors

    Science.gov (United States)

    Sendula, E.; Lamadrid, H. M.; Bodnar, R. J.

    2017-12-01

    Ultramafic and mafic rocks (e.g. peridotites, serpentinites and basalts) are being considered as possible targets for CO2 sequestration via mineral carbonation. The determination of reaction kinetics and the factors that control mineralization are important in order to understand and predict fluid-rock reactions between the injected CO2 and the host rocks. Here we present results of experiments focused on determining the reaction rates of carbonation of olivine as a function of initial CO2 concentration (20 mol% and 11 mol%) in the aqueous solution and temperature (100°C and 50°C). We used a recently developed experimental method (Lamadrid et al., 2017) that uses synthetic fluid inclusions as micro-reactors. The micro-reactor technique coupled with non-destructive Raman spectroscopy allows us to monitor the reaction progress in situ and in real time, by quantifying the amount of CO2 consumed in the reaction as a function of time. Results show a measurable decrease of CO2 density in the fluid inclusions as a result of the reaction between the CO2-bearing aqueous phase and olivine. Magnesite formation begins within several hours at 100°C and most of the CO2 was consumed within two days. At 50°C, however, magnesite nucleation and precipitation required weeks to months to begin, and the reaction rates were about an order of magnitude slower than in the experiments at 100°C. No significant differences were observed in the reaction rates as a function of initial CO2 concentration. The application of the synthetic fluid inclusion technique as micro-reactors coupled with non-destructive analytical techniques is a promising tool to monitor rates of fluid-rock reactions in situ and in real time, allowing detailed micron-scale investigations. The technique can be applied to a wide variety of chemical systems, host minerals, reaction products, fluid densities, temperatures, and different starting fluid compositions.

  9. Seismic microzoning from synthetic ground motion parameters: Case study, Santiago de Cuba

    International Nuclear Information System (INIS)

    Alvarez, Leonardo; Vaccari, Franco; Panza, Giuliano F.; Pico, Ramon

    2003-08-01

    Synthetic seismograms (P - SV and SH waves) have been calculated along 6 profiles in Santiago de Cuba basin, with a cutoff frequency of 5 Hz, by using the hybrid approach (modal summation for a regional (ID) structure plus finite differences for a local (2D) structure embedded in the first). They correspond to a scenario earthquake of M S = 7 that may occur in Oriente fault zone, directly south of the city. As initial data for a seismic microzoning, the characterisation of earthquake effects has been made considering several relative (2D/1D) quantities (PGDR, PGVR, PGAR, DGAR, I A R etc.) and functions representative of the ground motion behaviour in soil (2D) with respect to bedrock (ID). The functions are the response spectra ratio RSR(f), already routinely used in this kind of work, and the elastic energy input ratio E I R(f), defined, for the first time, in this paper. These data, sampled at 105 sites within all the profiles have been classified in two steps, using logical combinatory algorithms: connected sets and compact sets. In the first step, from the original ground motion parameters or functions extracted from the synthetic seismograms, 9 sets have been classified and the partial results show the spatial distribution of the soil behaviour as function of the component of motion. In the second step, the results of the classification of the 9 sets have been used as input for a further classification that shows a spatial distribution of sites with a quasi-homogeneous integral ground motion behaviour. By adding the available geological surface data, a microzoning scheme of Santiago de Cuba basin has been obtained. (author)

  10. Sub-pixel radiometry: a three-part study in generating synthetic imagery that incorporates sub-pixel variation

    Science.gov (United States)

    Paul, Sarah; Goodenough, Adam A.; Brown, Scott D.; Salvaggio, Carl

    2010-04-01

    A pixel represents the limit of spatial knowledge that can be represented in an image. It is represented as a single (perhaps spectral) digital count value that represents the energy propagating from a spatial portion of a scene. In any captured image, that single value is the result of many factors including the composition of scene optical properties within the projected pixel, the characteristic point spread function (or, equivalently, modulation transfer function) of the system, and the sensitivity of the detector element itself. This presentation examines the importance of sub-pixel variability in the context of generating synthetic imagery for remote sensing applications. The study was performed using the Digital Imaging and Remote Sensing Image Generation (DIRSIG) tool, an established ray-tracing based synthetic modeling system whose approach to sub-pixel computations was updated during this study. The paper examines three aspects of sub-pixel variability of interest to the remote sensing community. The first study simply looks at sampling frequency relative to structural frequency in a scene and the effects of aliasing on an image. The second considers the task of modeling a sub-pixel target whose signature would be mixed with background clutter, such as a small, hot target in a thermal image. The final study looks at capturing the inherent spectral variation in a single class of material, such as grass in hyperspectral imagery. Through each study we demonstrate in a quantitative fashion, the improved capabilities of DIRSIG's sub-pixel rendering algorithms.

  11. Radiation damage studies on synthetic NaCl crystals and natural rock salt for waste disposal applications

    International Nuclear Information System (INIS)

    Klaffky, R.W.; Swyler, K.J.; Levy, P.W.

    1979-01-01

    Radiation damage studies are being made on synthetic NaCl and natural rock salt crystals from various localities, including potential repository sites. Measurements are being made with equipment for recording the radiation induced F-center and colloid particle absorption bands during irradiation with 1.5 MeV electrons at various temperatures. A technique has been developed to resolve the overlapping F-center and colloid bands. The resulting spectra and curves of absorption vs. dose provide information on colloid particle size and concentration, activation energies for processes occurring during colloid formation, and additional data suggesting that both strain and radiation induced dislocations contribute to the colloid formation process

  12. Study of Brazil twin boundaries in synthetic quartz by means of simulations of X-ray topographs

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez-Manas, M.; Caballero, M.A. (Dept. de Estructura y Propriedades de los Materiales, Facultad de Ciencias, Univ. Cadiz (Spain)); Capelle, B.; Epelboin, Y. (Lab. de Mineralogie-Cristallographie, Univ. Paris-7, 75 (France))

    1993-02-01

    (0anti 111) twin boundaries of Y-cut synthetically-grown quartz crystals are studied by means of X-ray section topographs. The images show an anomalous contrast and no extinction can be found. Simulated images demonstrate that the twin boundaries are not simple planar defects. They may be described as lamellae of a non-diffracting material. Their thickness is of the order of 15 [mu]m and, within these boundaries, the Fourier components of the dielectric susceptibility are drastically reduced by one order of magnitude. (orig.).

  13. Study of mechanical properties and fracture mechanisms of synthetic fibers nylon-and-polyester type, used in engineering products

    International Nuclear Information System (INIS)

    Cardoso, Sergio Gomes

    2009-01-01

    Fibers are groups formed by molecular-chain-oriented filaments. Fibers play a fundamental role in human being's daily life and they can be found in several forms and geometries, such as filaments, yarns, beams, rope, fabric, composite, coatings, others. They are used in various segments such as civil, mechanical, electrical, electronics, military, naval, nautical, aviation, health, medicine, environment, communications, safety, space, others. Fibers are divided into two distinct classes: natural and chemical ones, which cover synthetic and man-made sub-classes. They can be produced from several materials, such as wool, cotton, rayon, flax, silk, rock, nylon, polyester, polyethylene, poly-propylene, aramid, glass, carbon, steel, ceramic, others. Globally, the participation of chemical fibers corresponds to approximately 59,9%, and the synthetic fiber polyester, the most used one, represents approximately 63% of the world market. Vital needs have led to the development of multi-function fibers and the focus has changed in the last 10 years with the use of nano technology for environmental responsibility and smart fibers. The study of mechanical properties and fracture mechanisms of fibers is of great relevance for characterization and understanding of causes as consequence of failures. For such reason, it was selected technical fabrics made of high performance synthetic fiber nylon-and-polyester type, used in engineered products such as tires, belts, hoses and pneumatic springs, which have been analyzed in each processing phase. Fiber samples were extracted after each processing phase to be analyzed, by traction destructive tests and scanning electron microscopy. The results of analysis of mechanical properties showed loss of resistance to temperature and multi axial stress during fiber processing phase. Through microscopy tests, it was possible to find contamination, surface stains, plastic deformations, scaling, variations in the fracture faces of the filaments and

  14. Study Of Blood Lead Levels, Hemoglobin & Plasma AscorbicAcid In ACarCompanyWelders

    Directory of Open Access Journals (Sweden)

    AR Dorosti

    2006-04-01

    Full Text Available Background and Aims: Background and aim: About 30-40% of lead entered the respiratorysystem, is absorbed to the bloodstream. Some studies have demonstrated that cigarette smokingresults in blood-lead levels elevation as well as decreased blood ascorbic acid. This study hasperformed on this issue in lead exposed welder workers.Method:Adescriptive cross-sectional study was performed to evaluate associations of smokinghabit with blood lead, hemoglobin and plasma ascorbic acid levels in 32 welders. All the casesused to work in a car factory in Tehran suburb as welders 8 hours a day. They were divided intothree groups based on blood lead level quartiles.The blood lead levels were determined by 8003 NAIOSH method and blood ascorbic acid levelwas determined by Lowery method. Results were compared (based on mean values usingindependent sample t-test and analysis of variance (ANOVA methods.Results: Results indicated that the blood lead levels in those who smoke 7+ cigarettes per day wassignificantly higher than those who smoke <7 cigarettes per day (p<0.05 or no smoking group(p<0.001. The hemoglobin concentrations in 7+ group was significantly lower than of the <7(p<0.01 and no smoking (p<0.05 groups.Conclusion :Smoking hait in population, who occupationally exposed to lead, causes an increaseexposure to lead and, hence, elevation of blood-lead levels as well as inhibition of hemoglobinsynthesis and therefore reduces hemoglobin concentration.

  15. Synthetic Botany.

    Science.gov (United States)

    Boehm, Christian R; Pollak, Bernardo; Purswani, Nuri; Patron, Nicola; Haseloff, Jim

    2017-07-05

    Plants are attractive platforms for synthetic biology and metabolic engineering. Plants' modular and plastic body plans, capacity for photosynthesis, extensive secondary metabolism, and agronomic systems for large-scale production make them ideal targets for genetic reprogramming. However, efforts in this area have been constrained by slow growth, long life cycles, the requirement for specialized facilities, a paucity of efficient tools for genetic manipulation, and the complexity of multicellularity. There is a need for better experimental and theoretical frameworks to understand the way genetic networks, cellular populations, and tissue-wide physical processes interact at different scales. We highlight new approaches to the DNA-based manipulation of plants and the use of advanced quantitative imaging techniques in simple plant models such as Marchantia polymorpha. These offer the prospects of improved understanding of plant dynamics and new approaches to rational engineering of plant traits. Copyright © 2017 Cold Spring Harbor Laboratory Press; all rights reserved.

  16. Synthetic Brainbows

    KAUST Repository

    Wan, Y.

    2013-06-01

    Brainbow is a genetic engineering technique that randomly colorizes cells. Biological samples processed with this technique and imaged with confocal microscopy have distinctive colors for individual cells. Complex cellular structures can then be easily visualized. However, the complexity of the Brainbow technique limits its applications. In practice, most confocal microscopy scans use different florescence staining with typically at most three distinct cellular structures. These structures are often packed and obscure each other in rendered images making analysis difficult. In this paper, we leverage a process known as GPU framebuffer feedback loops to synthesize Brainbow-like images. In addition, we incorporate ID shuffing and Monte-Carlo sampling into our technique, so that it can be applied to single-channel confocal microscopy data. The synthesized Brainbow images are presented to domain experts with positive feedback. A user survey demonstrates that our synthetic Brainbow technique improves visualizations of volume data with complex structures for biologists.

  17. In vitro studies of copper release from powder particles in synthetic biological media

    International Nuclear Information System (INIS)

    Midander, Klara; Wallinder, Inger Odnevall; Leygraf, Christofer

    2007-01-01

    The aim of this paper is to provide quantitative data on copper release from powder particles of different copper materials, including artificial copper patina, Cu 2 O and metallic Cu, when exposed to different synthetic biological media to simulate an inhalation scenario and/or skin contact. Generated data may contribute in risk assessment of potential health effects following exposure to and handling of various copper materials. All tests were performed in vitro to determine total copper concentrations, release rates of total copper, and to elucidate its time-dependence. The copper release process was interpreted in terms of specific surface area, surface morphology-, and composition. All powder materials show a time-dependent release process with total copper release rates less than 3 μg/cm 2 per hour at steady state conditions, for all media investigated. The importance of using relevant test media when simulating different interstitial lung conditions and difficulties encountered when comparing powder particles of essentially different properties are thoroughly discussed. - Copper release rates from particles are essential to assess potential health aspects

  18. Seismic microzoning from synthetic ground motion parameters Case study, Santiago de Cuba

    CERN Document Server

    Alvarez, L; Pico, R; Vaccari, F

    2003-01-01

    Synthetic seismograms (P - SV and SH waves) have been calculated along 6 profiles in Santiago de Cuba basin, with a cutoff frequency of 5 Hz, by using the hybrid approach (modal summation for a regional (ID) structure plus finite differences for a local (2D) structure embedded in the first). They correspond to a scenario earthquake of M sub S = 7 that may occur in Oriente fault zone, directly south of the city. As initial data for a seismic microzoning, the characterisation of earthquake effects has been made considering several relative (2D/1D) quantities (PGDR, PGVR, PGAR, DGAR, I sub A R etc.) and functions representative of the ground motion behaviour in soil (2D) with respect to bedrock (ID). The functions are the response spectra ratio RSR(f), already routinely used in this kind of work, and the elastic energy input ratio E sub I R(f), defined, for the first time, in this paper. These data, sampled at 105 sites within all the profiles have been classified in two steps, using logical combinatory algorith...

  19. Numerical Study of Balearic Meteotsunami Generation and Propagation under Synthetic Gravity Wave Forcing

    Science.gov (United States)

    Licer, Matjaz; Mourre, Baptiste; Troupin, Charles; Krietemeyer, Andreas; Tintoré, Joaquín

    2017-04-01

    A high resolution nested ocean modelling system forced by synthetic atmospheric gravity waves is used to investigate meteotsunami generation, amplification and propagation properties over the Mallorca-Menorca shelf (Balearic Islands, Western Mediterranean Sea). We determine how meteotsunami amplitude outside and inside of the Balearic port of Ciutadella depends on forcing gravity wave direction, speed and trajectory. Contributions of Mallorca shelves and Menorca Channel are quantified for different gravity wave forcing angles and speeds. Results indicate that the Channel is the key build-up region and that Northern and Southern Mallorca shelves do not significantly contribute to the amplitude of substantial harbour oscillations in Ciutadella. This fact seriously reduces early-warning alert times in cases of locally generated pressure perturbations. Tracking meteotsunami propagation paths in the Menorca Channel for several forcing velocities, we show that the Channel bathymetry serves as a focusing lens for meteotsunami waves whose paths are constrained by the forcing direction. Faster meteotsunamis are shown to propagate over deeper ocean regions, as required by the Proudman resonance. Meteotsunami speed under sub- and supercritical forcing is estimated and a first order estimate of its magnitude is derived. Meteotsunamis generated by the supercritical gravity waves are found to propagate with a velocity which is equal to an arithmetic mean of the gravity wave speed and local ocean barotropic wave speed.

  20. The impact of deuteration on natural and synthetic lipids: A neutron diffraction study.

    Science.gov (United States)

    Luchini, Alessandra; Delhom, Robin; Demé, Bruno; Laux, Valérie; Moulin, Martine; Haertlein, Michael; Pichler, Harald; Strohmeier, Gernot A; Wacklin, Hanna; Fragneto, Giovanna

    2018-02-05

    The structural investigation of cellular membranes requires access to model systems where the molecular complexity is representative of the cellular environment and that allow for the exploitation of structural techniques. Neutron scattering, and in particular neutron diffraction can provide unique and detailed information on the structure of lipid membranes. However, deuterated samples are desirable to fully exploit this powerful method. Recently, the extraction of lipids from microorganisms grown in deuterated media was demonstrated to be both an attracting route to obtain complex lipid mixtures resembling the composition of natural membranes, and to producing deuterated molecules in a very convenient way. A full characterization of these deuterated extracts is hence pivotal for their use in building up model membrane systems. Here we report the structural characterization of lipid extracts obtained from Pichia pastoris by means of neutron diffraction measurements. In particular, we compare the structure of membranes extracted from yeast cells grown in a standard culture medium and in a corresponding deuterated culture medium. The results show that the different molecular composition of the deuterated and protiated lipid extracts induce different structural organization of the lipid membranes. In addition, we compare these membranes composed of extracted yeast lipids with stacked bilayers prepared from synthetic lipid mixtures. Copyright © 2018 Elsevier B.V. All rights reserved.

  1. Understanding reactivity of two newly synthetized imidazole derivatives by spectroscopic characterization and computational study

    Science.gov (United States)

    Hossain, Mossaraf; Thomas, Renjith; Mary, Y. Sheena; Resmi, K. S.; Armaković, Stevan; Armaković, Sanja J.; Nanda, Ashis Kumar; Vijayakumar, G.; Van Alsenoy, C.

    2018-04-01

    Two newly synthetized imidazole derivatives (1-(4-methoxyphenyl)-4,5-dimethyl-1H-imidazole-2-yl acetate (MPDIA) and 1-(4-bromophenyl)-4,5-dimethyl-1H-imidazole-2-yl acetate (BPDIA)) have been prepared by solvent-free synthesis pathway and their specific spectroscopic and reactive properties have been discussed based on combined experimental and computational approaches. Aside of synthesis, experimental part of this work included measurements of IR, FT-Raman and NMR spectra. All of the aforementioned spectra were also obtained computationally, within the framework of density functional theory (DFT) approach. Additionally, DFT calculations have been used in order to investigate local reactivity properties based on molecular orbital theory, molecular electrostatic potential (MEP), average local ionization energy (ALIE), Fukui functions and bond dissociation energy (BDE). Molecular dynamics (MD) simulations have been used in order to obtain radial distribution functions (RDF), which were used for identification of the atoms with pronounced interactions with water molecules. MEP showed negative regions are mainly localized over N28, O29, O35 atoms, it is represent with red colour in rainbow color scheme for MPDIA and BPDIA (which are most reactive sites for electrophilic attack). The first order hyperpolarizabilities of MPDIA and BPDIA are 20.15 and 6.10 times that of the standard NLO material urea. Potential interaction with antihypertensive protein hydrolase.

  2. [Isolation, identification and lead adsorption study of lead-resistant Lactobacillus casei strains from feces of healthy newborns].

    Science.gov (United States)

    Shen, Wei; Yu, Qin-Fei; Wang, Yu-Hao; Zhang, Yi-Duo; Meng, Xiao-Jing; Fan, Hong-Ying

    2016-12-20

    To isolate and identify lead-resistant Lactobacillus casei strains with lead adsorption ability from the stool of healthy newborns as a new source of bacteria for developing lead-eliminating food products. MRS was used to isolate lead-resistant bacteria from the feces of 30 healthy and full-term neonates. A phylogenetic tree was constructed based on the morphological characteristics and 16S rRNA sequences of the isolated bacteria. Physiological and biochemical characterizations of the bacteria were performed according to the Berger's Systematic Bacteriology Handbook, followed by antimicrobial susceptibility test and acid-tolerant bile salt test. The adsorption capacity of Pb 2+ of the bacteria was determined by inductively coupled plasma-optical emission spectroscopy (ICP-OES). Three strains of Lactobacillus casei were isolated, which were resistant to penicillin and ceftriaxone and could tolerate the exposure to 500 mg/L Pb 2+ . Acid-tolerant bile salt test showed that the bacteria were resistant to culture in the presence of artificial gastric juice (pH 2.0) for 3 h, and their survival rate reached 62.5% following exposure to 0.3% bile salt for 8 h. The bacteria showed a Pb 2+ adsorption rate of 90.4% at a low Pb 2+ concentration (1 mg/L) and of 86.27% at a high Pb 2+ concentration (50 mg/L). Three Lactobacillus casei strains lead adsorption ability were isolated from the feces of newborns. These bacterial strains provide a new solution to alleviate lead poisoning by probiotic dietary.

  3. Study of lead phytoavailability for atmospheric industrial micronic and sub-micronic particles in relation with lead speciation

    Energy Technology Data Exchange (ETDEWEB)

    Uzu, G. [EcoLab UMR 5245 CNRS-INPT-UPS, ENSAT BP 32607 Auzeville Tolosane, 31326 Castanet Tolosan (France)], E-mail: gaelle.uzu@ensat.fr; Sobanska, S. [LASIR UMR 8516, Universite des Sciences et Technologies de Lille, Batiment C5, 59655 Villeneuve d' Ascq Cedex (France)], E-mail: Sophie.Sobanska@univ-lille1.fr; Aliouane, Y. [EcoLab UMR 5245 CNRS-INPT-UPS, ENSAT BP 32607 Auzeville Tolosane, 31326 Castanet Tolosan (France); Pradere, P. [Chemical Metal Treatment Company, STCM, 30-32 chemin de Fondeyre, 31200 Toulouse (France)], E-mail: p.pradere@stc-metaux.com; Dumat, C. [EcoLab UMR 5245 CNRS-INPT-UPS, ENSAT BP 32607 Auzeville Tolosane, 31326 Castanet Tolosan (France)], E-mail: camille.dumat@ensat.fr

    2009-04-15

    Particles from channelled emissions of a battery recycling facility were size-segregated and investigated to correlate their speciation and morphology with their transfer towards lettuce. Microculture experiments carried out with various calcareous soils spiked with micronic and sub-micronic particles (1650 {+-} 20 mg Pb kg{sup -1}) highlighted a greater transfer in soils mixed with the finest particles. According to XRD and Raman spectroscopy results, the two fractions presented differences in the amount of minor lead compounds like carbonates, but their speciation was quite similar, in decreasing order of abundance: PbS, PbSO{sub 4}, PbSO{sub 4}.PbO, {alpha}-PbO and Pb{sup 0}. Morphology investigations revealed that PM{sub 2.5} (i.e. Particulate Matter 2.5 composed of particles suspended in air with aerodynamic diameters of 2.5 {mu}m or less) contained many Pb nanoballs and nanocrystals which could influence lead availability. The soil-plant transfer of lead was mainly influenced by size and was very well estimated by 0.01 M CaCl{sub 2} extraction. - The soil-lettuce lead transfer from atmospheric industrial sub-micronic and micronic particles depends on particle size.

  4. Study of lead phytoavailability for atmospheric industrial micronic and sub-micronic particles in relation with lead speciation

    International Nuclear Information System (INIS)

    Uzu, G.; Sobanska, S.; Aliouane, Y.; Pradere, P.; Dumat, C.

    2009-01-01

    Particles from channelled emissions of a battery recycling facility were size-segregated and investigated to correlate their speciation and morphology with their transfer towards lettuce. Microculture experiments carried out with various calcareous soils spiked with micronic and sub-micronic particles (1650 ± 20 mg Pb kg -1 ) highlighted a greater transfer in soils mixed with the finest particles. According to XRD and Raman spectroscopy results, the two fractions presented differences in the amount of minor lead compounds like carbonates, but their speciation was quite similar, in decreasing order of abundance: PbS, PbSO 4 , PbSO 4 .PbO, α-PbO and Pb 0 . Morphology investigations revealed that PM 2.5 (i.e. Particulate Matter 2.5 composed of particles suspended in air with aerodynamic diameters of 2.5 μm or less) contained many Pb nanoballs and nanocrystals which could influence lead availability. The soil-plant transfer of lead was mainly influenced by size and was very well estimated by 0.01 M CaCl 2 extraction. - The soil-lettuce lead transfer from atmospheric industrial sub-micronic and micronic particles depends on particle size

  5. Association between hemochromatosis genotype and lead exposure among elderly men: the normative aging study.

    Science.gov (United States)

    Wright, Robert O; Silverman, Edwin K; Schwartz, Joel; Tsaih, Shring-Wern; Senter, Jody; Sparrow, David; Weiss, Scott T; Aro, Antonio; Hu, Howard

    2004-05-01

    Because body iron burden is inversely associated with lead absorption, genes associated with hemochromatosis may modify body lead burden. Our objective was to determine whether the C282Y and/or H63D hemochromatosis gene (HFE) is associated with body lead burden. Patella and tibia lead levels were measured by K X-ray fluorescence in subjects from the Normative Aging Study. DNA samples were genotyped for C282Y and H63D using polymerase chain reaction/restriction fragment length polymorphism (PCR/RFLP). A series of multivariate linear regression models were constructed with bone or blood lead as dependent variables; age, smoking, and education as independent variables; and C282Y or H63D as independent risk factors and/or effect modifiers. Of 730 subjects, 94 (13%) carried the C282Y variant and 183 (25%) carried the H63D variant. In the crude analysis, mean tibia, patella, and blood lead levels were consistently lower in carriers of either HFE variant compared with levels in subjects with wild-type genotypes. In multivariate analyses that adjusted for age, smoking, and education, having an HFE variant allele was an independent predictor of significantly lower patella lead levels (p lead accumulation after exposure. Among elderly men, subjects with HFE variants had lower patella lead levels. These effects may be mediated by alterations in lead toxicokinetics via iron metabolic pathways regulated by the HFE gene product and body iron stores.

  6. What does hydraulic tomography tell us about fractured geological media? A field study and synthetic experiments

    Science.gov (United States)

    Zha, Yuanyuan; Yeh, Tian-Chyi J.; Illman, Walter A.; Tanaka, Tatsuya; Bruines, Patrick; Onoe, Hironori; Saegusa, Hiromitsu

    2015-12-01

    Between 2005 and 2010, Japan Atomic Energy Agency conducted four long-term, independent pumping tests in a fractured granite formation at the Mizunami Underground Research Laboratory (MIU) site in Mizunami city, central Japan. During these tests, drawdowns were monitored at different depths along several deep boreholes. These tests become one of the few, if not the only, hydraulic tomographic survey conducted in the world over thousands of meters in a fractured geologic medium with several fault zones. We analyzed the drawdown-time data set associated with each pumping test independently, and then the data sets from all pumping tests jointly to derive the spatial distributions of hydraulic conductivity (K) and specific storage (Ss) of the medium. These estimated distributions revealed some large-scale high K and low K zones. While the low K zones corroborated well with known low permeable layers and fault based on geological investigations, there were no clear geological features that can be related to the large-scale high K zones. In order to understand and substantiate these high and low K zones, we simulated a hydraulic tomographic survey in a synthetic fractured aquifer, which bears similar geologic features (i.e., formations, fractures, and faults) at the MIU site, with exception that the hydraulic properties, fracture and fault distributions were known exactly. Results of the simulation show that not only are the identified high K zones related to fracture networks connected with pumping and observation locations of each pumping test but also their values reflect the degree of connectivity of the network. Afterward, we investigated the extent of the improvement of characterization of the fault and fractures through the use of deploying dense monitoring intervals and late-time flux measurements.

  7. Novel studies of molecular orientation in synthetic polymeric membranes for gas separation

    International Nuclear Information System (INIS)

    Ismail, Ahmad Fauzi

    1998-01-01

    The main objective of this investigation was to produce a super-selective asymmetric membrane for gas separation. To achieve this, molecular orientation induced by rheological conditions during membrane fabrication was investigated and related to the gas separation performance of flat sheet and hollow fiber membranes. Infrared dichroism, a spectroscopic technique, was developed in the first phase of the research to directly measure molecular orientation in flat sheet membranes. The degree of molecular orientation was found to increase with increasing shear during fabrication which enhanced both pressure-normalised flux and selectivity of the coated membranes. The rheology of polymer solutions and the mechanism of molecular orientation have been treated in detail for membrane production. This is a novel approach since previous fundamental work has focused on the phase inversion process. The current study showed that rheological conditions during membrane fabrication have the utmost importance in enhancing membrane selectivity. The effects of molecular orientation at greater shear, as experienced by hollow fiber membranes during extrusion through the spinneret channel, were investigated in the second phase of this research. In order to produce a good quality fiber, a unique tube-in-orifice spinneret and a modified hollow fiber spinning rig were designed and fabricated. Thus the combined effects of reduced water activity in the bore coagulant during hollow fiber spinning and rheologically induced molecular orientation were investigated. The selectivity of the coated high shear hollow fiber membranes was heightened and even surpassed the recognised intrinsic selectivity of the polymer. Pressure-normalised flux also increased with increasing shear rate. In the third phase of this research phase inversion conditions were further optimised to give a superior skin layer and thus provide an even better platform for the advantageous effects of molecular orientation. These

  8. [Lead intakes by different age-sex population groups from Chinese total diet study in 2000].

    Science.gov (United States)

    Zhang, Lei; Gao, Junquan; Li, Xiaowei

    2007-07-01

    To estimate the dietary lead intakes by different age-sex population groups in China. The lead concentrations of food sample from 3rd Chinese total diet study were determined, and then were combined with the food consumption by population of ten age-sex groups, The lead intakes, and its distribution and dietary sources were obtained. It was found that the mean and median concentrations of lead in all food samples were 0.118 and 0.052mg/kg, respectively. The highest concentration of individual sample and mean concentrations of lead in preserved egg were 8.964mg/kg and 2.577mg/kg, respectively. The vegetable samples in Hubei Province were heavily contaminated. The lead intakes by different age-sex groups were estimated to be 54.9-112.7microg/day. The average dietary lead intakes by 2-7 years old group could reach 86.1% of PTWI, and individual lead intakes by about 30% children in this group exceed PTWI. But the average dietary lead intakes of other age-sex population groups ranged from 42.8% to 86.1% of PTWI. The main sources of dietary lead were cereals and vegetables in ten age-sex population groups, and could reach 72%-80% of total lead intakes. Although the dietary lead intakes by different age-sex population groups are all lower than PTWI, it should be decreased to a lower level. Moreover, the dietary exposures to lead are higher enough for 2-7 years old children and population in some provinces to be considered seriously.

  9. Study of Baryon and Antibaryon Spectra in Lead Lead Interactions at 160 GeV/c per Nucleon

    CERN Multimedia

    2002-01-01

    % WA97 \\\\ \\\\ Hyperons are expected to be a useful probe for the dynamics of hadronic matter under extreme conditions. In particular the onset of a Quark-Gluon Plasma phase in a heavy ion collision is expected to enhance the hyperon yield with respect to normal hadronic interactions. \\\\ \\\\WA97 aims to measure the spectra of strange particles and in particular of hyperons and antihyperons produced in ultrarelativistic lead-lead interactions and to compare them with those from proton initiated reactions. The experiment covers central rapidity down to transverse momenta of a few hundred MeV/c. The experimental setup consists of: an array of multiplicity counters, a silicon based decay detector made of pixels, located in the CERN-OMEGA Spectrometer, an array of pad cathode MWPCs used as lever arm detectors and a zero degree hadron calorimeter. \\\\ \\\\

  10. INTRUDER STATES IN THE LEAD REGION, STUDIED BY ALPHA-DECAY

    NARCIS (Netherlands)

    WAUTERS, J; DENDOOVEN, P; HUYSE, M; REUSEN, G; VANDUPPEN, P; LIEVENS, P; KIRCHNER, R; KLEPPER, O; ROECKL, E; Neugart, R; Wohr, A

    1993-01-01

    The alpha decay of nuclei around the Z=82 closed proton shell is a powerful tool for the study of shape coexistence and intruder states in the lead region. Systematic measurements of alpha-decay properties of even-even mercury, lead, polonium and radon nuclei have been performed. From the deduced

  11. Cost and design study for electric vehicle lead--acid batteries

    Energy Technology Data Exchange (ETDEWEB)

    1977-01-01

    A design and cost study for electric-vehicle lead--acid batteries is presented; a research and development program leading to demonstration and testing of 20- to 30-kWh batteries is proposed. Both flat pasted and tubular positive electrodes are included. Detailed testing programs are set forth. 110 figures, 8 tables (RWR)

  12. Case Studies of Leading Edge Small Urban High Schools. Relevance Strategic Designs: 4. Boston Arts Academy

    Science.gov (United States)

    Shields, Regis Anne; Ireland, Nicole; City, Elizabeth; Derderian, Julie; Miles, Karen Hawley

    2008-01-01

    This report is one of nine detailed case studies of small urban high schools that served as the foundation for the Education Resource Strategies (ERS) report "Strategic Designs: Lessons from Leading Edge Small Urban High Schools." These nine schools were dubbed "Leading Edge Schools" because they stand apart from other high…

  13. Case Studies of Leading Edge Small Urban High Schools. Relevance Strategic Designs: 6. Perspectives Charter School

    Science.gov (United States)

    Shields, Regis Anne; Ireland, Nicole; City, Elizabeth; Derderian, Julie; Miles, Karen Hawley

    2008-01-01

    This report is one of nine detailed case studies of small urban high schools that served as the foundation for the Education Resource Strategies (ERS) report "Strategic Designs: Lessons from Leading Edge Small Urban High Schools." These nine schools were dubbed "Leading Edge Schools" because they stand apart from other high…

  14. Synthetic Metabolic Pathways

    DEFF Research Database (Denmark)

    topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and tips on troubleshooting and avoiding known pitfalls. Authoritative and practical, Synthetic Metabolic Pathways: Methods and Protocols aims to ensure successful results in the further study...

  15. Synthetic growth reference charts

    NARCIS (Netherlands)

    Hermanussen, Michael; Stec, Karol; Aßmann, Christian; Meigen, Christof; Van Buuren, Stef

    2016-01-01

    Objectives: To reanalyze the between-population variance in height, weight, and body mass index (BMI), and to provide a globally applicable technique for generating synthetic growth reference charts. Methods: Using a baseline set of 196 female and 197 male growth studies published since 1831, common

  16. LC/ESI-MS/MS method for quantification of 28 synthetic cannabinoids in neat oral fluid and its application to preliminary studies on their detection windows.

    Science.gov (United States)

    Kneisel, Stefan; Speck, Michael; Moosmann, Bjoern; Corneillie, Todd M; Butlin, Nathaniel G; Auwärter, Volker

    2013-05-01

    Serum and urine samples are commonly used for the analysis of synthetic cannabinoids in biofluids; however, their utilization as analytical matrices for drug abstinence control features some substantial drawbacks. While for blood collection invasive sampling is inevitable, the urinary analysis of synthetic cannabinoids is limited by the lack of available reference standards of the respective major metabolites. Moreover, the long detectability of synthetic cannabinoids in both matrices hampers the identification of a recent synthetic cannabinoid use. This article describes the development, validation and application of an LC/ESI-MS/MS method for the quantification of 28 synthetic cannabinoids in neat oral fluid (OF) samples. OF samples were prepared by protein precipitation using ice-cold acetonitrile. Chromatographic separation was achieved by gradient elution on a Luna Phenyl Hexyl column (50 × 2 mm, 5 μm), while detection was carried out on a QTrap 4000 instrument in positive ionization mode. The limits of detection ranged from 0.02 to 0.40 ng/mL, whereas the lower limits of quantification ranged from 0.2 to 4.0 ng/mL. The method was applied to authentic samples collected during two preliminary studies in order to obtain insights into the general detectability and detection windows of synthetic cannabinoids in this matrix. The results indicate that synthetic cannabinoids are transferred from the blood stream into OF and vice versa only at a very low rate. Therefore, positive OF samples are due to contamination of the oral cavity during smoking. As these drug-contaminations could be detected up to approximately 2 days, neat oral fluid appears to be well suited for detection of a recent synthetic cannabinoid use.

  17. Slurry growth, gas retention, and flammable gas generation by Hanford radioactive waste tanks: Synthetic waste studies, FY 1991

    Energy Technology Data Exchange (ETDEWEB)

    Bryan, S.A.; Pederson, L.R.; Ryan, J.L.; Scheele, R.D.; Tingey, J.M.

    1992-08-01

    Of 177 high-level waste storage tanks on the Hanford Site, 23 have been placed on a safety watch list because they are suspected of producing flammable gases in flammable or explosive concentrate. One tankin particular, Tank 241-SY-101 (Tank 101-SY), has exhibited slow increases in waste volume followed by a rapid decrease accompanied by venting of large quantities of gases. The purpose of this study is to help determine the processes by which flammable gases are produced, retained, and eventually released from Tank 101-SY. Waste composition data for single- and double-shell waste tanks on the flammable gas watch listare critically reviewed. The results of laboratory studies using synthetic double-shell wastes are summarized, including physical and chemical properties of crusts that are formed, the stoichiometry and rate ofgas generation, and mechanisms responsible for formation of a floating crust.

  18. Slurry growth, gas retention, and flammable gas generation by Hanford radioactive waste tanks: Synthetic waste studies, FY 1991

    International Nuclear Information System (INIS)

    Bryan, S.A.; Pederson, L.R.; Ryan, J.L.; Scheele, R.D.; Tingey, J.M.

    1992-08-01

    Of 177 high-level waste storage tanks on the Hanford Site, 23 have been placed on a safety watch list because they are suspected of producing flammable gases in flammable or explosive concentrate. One tankin particular, Tank 241-SY-101 (Tank 101-SY), has exhibited slow increases in waste volume followed by a rapid decrease accompanied by venting of large quantities of gases. The purpose of this study is to help determine the processes by which flammable gases are produced, retained, and eventually released from Tank 101-SY. Waste composition data for single- and double-shell waste tanks on the flammable gas watch listare critically reviewed. The results of laboratory studies using synthetic double-shell wastes are summarized, including physical and chemical properties of crusts that are formed, the stoichiometry and rate ofgas generation, and mechanisms responsible for formation of a floating crust

  19. A study on synthetic method and material characteristics of magnesium ammine chloride as ammonia transport materials for solid SCR

    International Nuclear Information System (INIS)

    Shin, Jong Kook; Yoon, Cheon Seog; Kim, Hong Suk

    2015-01-01

    Among various ammonium salts and metal ammine chlorides used as solid materials for the sources of ammonia with solid SCR for lean NOx reduction, magnesium ammine chloride was taken up for study in this paper because of its ease of handling and safety. Lab-scale synthetic method of magnesium ammine chloride were studied for different durations, temperatures, and pressures with proper ammonia gas charged, as a respect of ammonia gas adsorption rate(%). To understand material characteristics for lab-made magnesium ammine chloride, DA, IC, FT-IR, XRD and SDT analyses were performed using the published data available in literature. From the analytical results, the water content in the lab-made magnesium ammine chloride can be determined. A new test procedure for water removal was proposed, by which the adsorption rate of lab-made sample was found to be approximately 100%

  20. Study of the effects induced by lead on the emulsion films of the OPERA experiment

    CERN Document Server

    Anokhina, A.; Ariga, A.; Arrabito, L.; Autiero, D.; Badertscher, A.; Bay, F.; Bergnoli, A.; Bersani Greggio, F.; Besnier, M.; Bick, D.; Bozza, C.; Brugiere, T.; Brugnera, R.; Brunetti, G.; Buontempo, S.; Carrara, E.; Cazes, A.; Chaussard, L.; Chernyavsky, M.; Chiarella, V.; Chon-Sen, N.; Chukanov, A.; Consiglio, L.; Cozzi, M.; Dal Corso, F.; D'Amato, G.; D'Ambrosio, N.; De Lellis, G.; Declais, Y.; De Serio, M.; Di Capua, F.; Di Ferdinando, D.; Di Giovanni, A.; Di Marco, N.; Di Troia, C.; Dmitrievski, S.; Dominjon, A.; Dracos, M.; Duchesneau, D.; Dulach, B.; Dusini, S.; Ebert, J.; Egorov, O.; Enikeev, R.; Ereditato, A.; Esposito, L.S.; Favier, J.; Felici, G.; Ferber, T.; Fini, R.; Franceschi, A.; Fukuda, T.; Fukushima, C.; Galkin, V.I.; Galkin, V.A.; Garfagnini, A.; Giacomelli, G.; Giorgini, M.; Goellnitz, C.; Golubkov, D.; Gornoushkin, Y.; Grella, G.; Grianti, F.; Guler, M.; Gusev, G.; Gustavino, C.; Hagner, Caren; Hara, T.; Hierholzer, M.; Hiramatsu, S.; Hoshino, Kaoru; Ieva, M.; Jakovcic, K.; Janicsko Csathy, J.; Janutta, B.; Jollet, C.; Juget, F.; Kawai, T.; Kazuyama, M.; Kim, S.H.; Kimura, M.; Knuesel, J.; Kodama, K.; Komatsu, M.; Kose, U.; Kreslo, I.; Laktineh, I.; Lazzaro, C.; Lenkeit, J.; Ljubicic, A.; Longhin, Andrea; Lutter, G.; Manai, K.; Mandrioli, G.; Manzoor, S.; Marotta, A.; Marteau, J.; Matsuoka, H.; Mauri, N.; Meisel, F.; Meregaglia, A.; Messina, M.; Migliozzi, P.; Miyamoto, S.; Monacelli, P.; Morishima, K.; Moser, U.; Muciaccia, M.T.; Naganawa, N.; Naka, T.; Nakamura, M.; Nakamura, T.; Nakano, T.; Nikitina, V.; Niwa, K.; Nonoyama, Y.; Ogawa, S.; Osedlo, V.; Ossetski, D.; Paoloni, A.; Park, B.D.; Park, I.G.; Pastore, A.; Patrizii, L.; Pennacchio, E.; Pessard, H.; Pistillo, C.; Polukhina, N.; Pozzato, M.; Pretzl, K.; Publichenko, P.; Pupilli, F.; Roganova, T.; Rosa, G.; Rostovtseva, I.; Rubbia, A.; Russo, A.; Ryazhskaya, O.; Ryzhikov, D.; Sato, Y.; Sato, O.; Saveliev, V.; Sazhina, G.; Schembri, A.; Scotto Lavina, L.; Shibuya, H.; Simone, S.; Sioli, M.; Sirignano, C.; Sirri, G.; Song, J.S.; Spinetti, M.; Stanco, L.; Starkov, N.; Stipcevic, M.; Strauss, T.; Strolin, Paolo Emilio; Sugonyaev, V.; Taira, Y.; Takahashi, S.; Tenti, M.; Terranova, F.; Tioukov, V.; Togo, V.; Tolun, P.; Tsarev, V.; Tufanli, S.; Ushida, N.; Valieri, C.; Vilain, P.; Vladimirov, M.; Votano, L.; Vuilleumier, J.L.; Wilquet, G.; Wonsak, B.; Wurtz, J.; Yoon, C.S.; Yoshida, J.; Zaitsev, Y.; Zemskova, S.; Zghiche, A.; Zimmermann, R.

    2008-01-01

    The OPERA neutrino oscillation experiment is based on the use of the Emulsion Cloud Chamber (ECC). In the OPERA ECC, nuclear emulsion films acting as very high precision tracking detectors are interleaved with lead plates providing a massive target for neutrino interactions. We report on studies related to the effects occurring from the contact between emulsion and lead. A low radioactivity lead is required in order to minimize the number of background tracks in emulsions and to achieve the required performance in the reconstruction of neutrino events. It was observed that adding other chemical elements to the lead, in order to improve the mechanical properties, may significantly increase the level of radioactivity on the emulsions. A detailed study was made in order to choose a lead alloy with good mechanical properties and an appropriate packing technique so as to have a low enough effective radioactivity.

  1. A lead isotope distribution study in swine tissue using ICP-MS

    Science.gov (United States)

    May, T.W.; Wiedmeyer, Ray H.; Brown, L.D.; Casteel, S.W.

    1999-01-01

    In the United States lead is an ubiquitous environmental pollutant that is a serious human health hazard, especially for women of childbearing age, developing fetuses, and young children. Information concerning the uptake and distribution of lead to maternal and fetal tissues during pregnancy is poorly documented. A study was designed using domestic swine and lead isotope enrichment methodology to focus on maternal absorption and distribution of lead into bone and soft tissues, including the fetal compartment, under varying conditions of oral lead exposure and during altered physiological states (pregnant vs unbred). Total lead levels and Pb207/Pb206 ratios in bone (femur and vertebra), blood, and soft tissues (liver, kidney, brain) were determined by ICP-MS. Lead in fetal tissues derived from maternal bone could be differentiated from that derived from exogenous dosing. Unbred swine absorbed much less lead than pregnant females receiving the same dose. The accuracy and precision of ICP-MS at the instrumental level and for the entire method (sample collection, digestion, and analysis) were evaluated for both Pb207/Pb206 ratios and total lead. Several changes were suggested in method design to improve both instrumental and total method precision.

  2. Comparative study of lead borate and bismuth lead borate glass systems as gamma-radiation shielding materials

    International Nuclear Information System (INIS)

    Singh, Narveer; Singh, Kanwar Jit; Singh, Kulwant; Singh, Harvinder

    2004-01-01

    Gamma-ray mass attenuation coefficients have been measured experimentally and calculated theoretically for PbO-B 2 O 3 and Bi 2 O 3 -PbO-B 2 O 3 glass systems using narrow beam transmission method. These values have been used to calculate half value layer (HVL) parameter. These parameters have also been calculated theoretically for some standard radiation shielding concretes at same energies. Effect of replacing lead by bismuth has been analyzed in terms of density, molar volume and mass attenuation coefficient

  3. On the study of wavy leading-edge vanes to achieve low fan interaction noise

    Science.gov (United States)

    Tong, Fan; Qiao, Weiyang; Xu, Kunbo; Wang, Liangfeng; Chen, Weijie; Wang, Xunnian

    2018-04-01

    The application of wavy leading-edge vanes to reduce a single-stage axial fan noise is numerically studied. The aerodynamic and acoustic performance of the fan is numerically investigated using a hybrid unsteady Reynolds averaged Navier-Stokes (URANS)/acoustic analogy method (Goldstein equations). First, the hybrid URANS/Goldstein method is developed and successfully validated against experiment results. Next, numerical simulations are performed to investigate the noise reduction effects of the wavy leading-edge vanes. The aerodynamic and acoustic performance is assessed for a fan with vanes equipped with two different wavy leading-edge profiles and compared with the performance of conventional straight leading-edge vanes. Results indicate that a fan with wavy leading-edge vanes produces lower interaction noise than the baseline fan without a significant loss in aerodynamic performance. In fact, it is demonstrated that wavy leading-edge vanes have the potential to lead to both aerodynamic and acoustic improvements. The two different wavy leading-edge profiles are shown to successfully reduce the fan tone sound power level by 1.2 dB and 4.3 dB, respectively. Fan efficiency is also improved by about 1% with one of the tested wavy leading-edge profiles. Large eddy simulation (LES) is also performed for a simplified fan stage model to assess the effects of wavy leading-edge vanes on the broadband fan noise. Results indicate that the overall sound power level of a fan can be reduced by about 4 dB with the larger wavy leading-edge profile. Finally, the noise reduction mechanisms are investigated and analysed. It is found that the wavy leading-edge profiles can induce significant streamwise vorticity around the leading-edge protuberances and reduce pressure fluctuations (especially at locations of wavy leading-edge hills) and unsteady forces on the stator vanes. The underlying mechanism of the reduced pressure fluctuations is also discussed by examining the magnitude

  4. Treatability Study Report for In SITU Lead Immobilization Using Phosphate-Based Binders

    National Research Council Canada - National Science Library

    Bricka, R. M; Marwaha, Anirudha; Fabian, Gene L

    2008-01-01

    .... The treatability study described in this report was designed to develop the information necessary to support the immobilization of lead contaminants in soil by in situ treatment with phosphate-based binders...

  5. Studies of lead pollution in the air of Shanghai by multiple techniques

    International Nuclear Information System (INIS)

    Tan, M.G.; Zhang, G.L.; Li, X.L.; Zhang, Y.X.; Yue, W.S.; Chen, J.M.; Wang, Y.S.; Li, A.G.; Li, Y.; Zhang, Y.M.; Shan, Z.C.

    2005-01-01

    Lead pollution in atmosphere has been one of the worrisome environmental problems since the tetraethyl lead was used as an antiknock agent in combustion engines. The presence of lead in urban air, even at low doses, may cause neurological impairments of fetuses and young children. Studies also show that lead may be a factor in high blood pressure and subsequent heart disease. Atmospheric lead has various origins, such as gasoline, industrial emissions and coal burning etc. The present work reports the lead levels in air particulate matter samples of PM 10 collected in recent years to evaluate the effect of the use of unleaded gasoline in Shanghai since 1997. The chemical species of lead in PM 10 and their origins were also studied. To our knowledge it is a first time to give an estimation of lead contribution to air in a city from different emission sources quantitatively. Proton-induced X-ray emission analysis (PIXE), proton microprobe (μ-PIXE), inductively coupled plasma-mass spectrometry (ICP-MS) and X-ray absorption fine structure (XAFS) techniques were used to study the concentration, the chemical species and the source assignment of Pb in the atmospheric aerosol particles of PM 10 . Average values of 369±74. ng/m 3 and 237±45 ng/m 3 of Pb concentration were obtained from the 19 monitor sites in Shanghai in the winter of 2002 and 2003, respectively. Comparing with the earlier data of 466 ng/m 3 in 1997 and 515 ng/m 3 in 2001, it can be observed that the yearly mean lead levels in PM 10 decline significantly. However, it is also found that rather high levels of lead still remain. in the air of Shanghai after the use of unleaded gasoline. The results of XAFS showed that PbCl 2 , PbSO 4 and PbO were probably the main chemical forms of Pb in atmospheric particulate matter. Based on the lead isotope ratios technique and chemical mass balance analysis, the calculation showed that the main emission sources of Pb in the atmosphere of Shanghai were coal combustors

  6. High-pressure optical spectroscopy and X-ray diffraction studies on synthetic cobalt aluminum silicate garnet

    DEFF Research Database (Denmark)

    N. Taran, Michail; Nestola, Fabrizio; Ohashi, Haruo

    2007-01-01

    The pressure-induced behavior of spin-allowed dd-bands of VIIICo2+ in the absorption spectra of synthetic Co3Al2Si3O12 garnet was studied from 10-4 to 13 GPa. The plots of the peak energy vs. pressure for the three sharpest well resolved bands at ca. 5160, 17 680, and 18 740 cm-1 display small...... but discernible breaks in linear relations between 4 and 5 GPa. Datafromsingle-crystalX-raydiffractionData from single-crystal X-ray diffraction likewise show discontinuities in trends of CoO8 polyhedral volume and distortion, and Co-O and Si-O bond distances over this pressure range. These effects are related...

  7. Small-angle neutron and X-ray scattering studies of supraatomic structure of synthetic quartz irradiated by fast neutrons

    International Nuclear Information System (INIS)

    Lebedev, V.M.; Lebedev, V.T.; Orlov, S.P.; Golubkov, V.V.; Pevzner, B.Z.; Tolstikhin, I.N.

    2008-01-01

    Quartz nanostructures have been simulated for the investigation into diffusion of gases in the Earth crust. The nanostructure of synthetic quartz irradiated by fast neutrons with energy E n >0.1 MeV was studied by neutron and X-ray small-angle scattering. The range of neutron fluence is of 10 17 cm -2 up to 2x10 -2 0 cm -2 . In the irradiated samples the different kinds of defects such as point-like, extended linear (dislocations) and globular (size ∼100 nm, amorphous phase nuclei) were observed. The density of highly irradiated quartz (fluence 2x10 20 cm -2 ) is shown to decrease by 0.39 g/cm 2 and reach the magnitude of 2.260 g/cm 2 corresponding to 100% metamict phase. The first results of model structures helium saturation have been received [ru

  8. Ga(III) chelates of amphiphilic DOTA-based ligands: synthetic route and in vitro and in vivo studies

    Energy Technology Data Exchange (ETDEWEB)

    Fontes, Andre [Centro de Quimica, Campus de Gualtar, Universidade do Minho, 4710-057, Braga (Portugal); Prata, M. Isabel M. [IBILI, Faculdade de Medicina, Universidade de Coimbra, 3548, Coimbra (Portugal); Geraldes, Carlos F.G.C. [Departamento de Ciencias da Vida, Faculdade de Ciencias e Tecnologia, Universidade de Coimbra, 3001-401, Coimbra (Portugal); Centro de Neurociencias e Biologia Celular, Universidade de Coimbra, 3001-401, Coimbra (Portugal); Andre, Joao P., E-mail: jandre@quimica.uminho.p [Centro de Quimica, Campus de Gualtar, Universidade do Minho, 4710-057, Braga (Portugal)

    2011-04-15

    In this work, we report on a synthetic strategy using amphiphilic DOTA (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid)-based chelators bearing a variable-sized {alpha}-alkyl chain at one of the pendant acetate arms (from 6 to 14 carbon atoms), compatible with their covalent coupling to amine-bearing biomolecules. The amphiphilic behavior of the micelles-forming Ga(III) chelates (critical micellar concentration), their stability in blood serum and their lipophilicity (logP) were investigated. Biodistribution studies with the {sup 67}Ga-labeled chelates were performed in Wistar rats, which showed a predominant liver uptake with almost no traces of the radiochelates in the body after 24 h.

  9. A synthetic study on constaining a 2D density-dependent saltwater intrusion model using electrical imaging data

    DEFF Research Database (Denmark)

    Antonsson, Arni Valur; Nguyen, Frederic; Engesgaard, Peter Knudegaard

    of obtainable data. These factors can seriously hinder a successful monitoring strategy and consequently limit the reliability of the calibrated model. An effective alternative to conventional measurements is the use of geophysical methods to monitor changes in the subsurface e.g. salinity distribution...... calibration is determined by different factors, where both data quantity and quality is of crucial importance. Typically the availability of conventional monitoring installations (e.g. depth specific monitoring wells for salinity measurements) and the cost of constructing new ones limit the amount....... Compared to conventional methods, which only give (few) point information, electrical images can give data over large spatial distances but that can be of great value for groundwater modeling purposes. The aim of this study is to investigate in a synthetic way, the applicability of using electrical images...

  10. Comparative study of the efficiency of synthetic and natural mediators in laccase-assisted bleaching of eucalyptus kraft pulp.

    Science.gov (United States)

    Moldes, D; Díaz, M; Tzanov, T; Vidal, T

    2008-11-01

    The natural phenolic compounds syringaldehyde and vanillin were compared to the synthetic mediators 1-hydroxybenzotriazole, violuric acid and promazine in terms of boosting efficiency in a laccase-assisted biobleaching of eucalyptus kraft pulp. Violuric acid and 1-hydroxybenzotriazole revealed to be the most effective mediators of the bioprocess. Nevertheless, laccase-syringaldehyde system also improved the final pulp properties (28% delignification and 63.5% ISO brightness) compared to the process without mediator (23% and 61.5% respectively), in addition to insignificant denaturation effect over laccase. The efficiency of the biobleaching process was further related to changes in non-conventionally used optical and chromatic parameters of pulp, such as (L*), chroma (C*) and dye removal index (DRI) showing good correlation. Adverse coupling reactions of the natural phenolic mediators on pulp lignin were predicted by electrochemical studies, demonstrating the complexity of the laccase-mediator reaction on pulp.

  11. Cumulative Lead Exposure and Tooth Loss in Men: The Normative Aging Study

    Science.gov (United States)

    Arora, Manish; Weuve, Jennifer; Weisskopf, Marc G.; Sparrow, David; Nie, Huiling; Garcia, Raul I.; Hu, Howard

    2009-01-01

    Background Individuals previously exposed to lead remain at risk because of endogenous release of lead stored in their skeletal compartments. However, it is not known if long-term cumulative lead exposure is a risk factor for tooth loss. Objectives We examined the association of bone lead concentrations with loss of natural teeth. Methods We examined 333 men enrolled in the Veterans Affairs Normative Aging Study. We used a validated K-shell X-ray fluorescence (KXRF) method to measure lead concentrations in the tibial midshaft and patella. A dentist recorded the number of teeth remaining, and tooth loss was categorized as 0, 1–8 or ≥ 9 missing teeth. We used proportional odds models to estimate the association of bone lead biomarkers with tooth loss, adjusting for age, smoking, diabetes, and other putative confounders. Results Participants with ≥ 9 missing teeth had significantly higher bone lead concentrations than those who had not experienced tooth loss. In multivariable-adjusted analyses, men in the highest tertile of tibia lead (> 23 μg/g) and patella lead (> 36 μg/g) had approximately three times the odds of having experienced an elevated degree of tooth loss (≥ 9 vs. 0–8 missing teeth or ≥ 1 vs. 0 missing teeth) as those in the lowest tertile [prevalence odds ratio (OR) = 3.03; 95% confidence interval (CI), 1.60–5.76 and OR = 2.41; 95% CI, 1.30–4.49, respectively]. Associations between bone lead biomarkers and tooth loss were similar in magnitude to the increased odds observed in participants who were current smokers. Conclusion Long-term cumulative lead exposure is associated with increased odds of tooth loss. PMID:20019902

  12. BNL Building 650 lead decontamination and treatment feasibility study. Final report

    International Nuclear Information System (INIS)

    Kalb, P.D.; Cowgill, M.G.; Milian, L.W.

    1995-10-01

    Lead has been used extensively at Brookhaven National Laboratory (BNL) for radiation shielding in numerous reactor, accelerator and other research programs. A large inventory of excess lead (estimated at 410,000 kg) in many shapes and sizes is currently being stored. Due to it's toxicity, lead and soluble lead compounds are considered hazardous waste by the Environmental Protection Agency. Through use at BNL, some of the lead has become radioactive, either by contamination of the surface or through activation by neutrons or deuterons. This study was conducted at BNL's Environmental and Waste Technology Center for the BNL Safety and Environmental Protection Division to evaluate feasibility of various treatment options for excess lead currently being stored. The objectives of this effort included investigating potential treatment methods by conducting a review of the literature, developing a means of screening lead waste to determine the radioactive characteristics, examining the feasibility of chemical and physical decontamination technologies, and demonstrating BNL polyethylene macro-encapsulation as a means of treating hazardous or mixed waste lead for disposal. A review and evaluation of the literature indicated that a number of physical and chemical methods are available for decontamination of lead. Many of these techniques have been applied for this purpose with varying degrees of success. Methods that apply mechanical techniques are more appropriate for lead bricks and sheet which contain large smooth surfaces amenable to physical abrasion. Lead wool, turnings, and small irregularly shaped pieces would be treated more effectively by chemical decontamination techniques. Either dry abrasion or wet chemical methods result in production of a secondary mixed waste stream that requires treatment prior to disposal

  13. Genome-wide association study of blood lead shows multiple associations near ALAD.

    Science.gov (United States)

    Warrington, Nicole M; Zhu, Gu; Dy, Veronica; Heath, Andrew C; Madden, Pamela A F; Hemani, Gibran; Kemp, John P; Mcmahon, George; St Pourcain, Beate; Timpson, Nicholas J; Taylor, Caroline M; Golding, Jean; Lawlor, Debbie A; Steer, Colin; Montgomery, Grant W; Martin, Nicholas G; Davey Smith, George; Evans, David M; Whitfield, John B

    2015-07-01

    Exposure to high levels of environmental lead, or biomarker evidence of high body lead content, is associated with anaemia, developmental and neurological deficits in children, and increased mortality in adults. Adverse effects of lead still occur despite substantial reduction in environmental exposure. There is genetic variation between individuals in blood lead concentration but the polymorphisms contributing to this have not been defined. We measured blood or erythrocyte lead content, and carried out genome-wide association analysis, on population-based cohorts of adult volunteers from Australia and UK (N = 5433). Samples from Australia were collected in two studies, in 1993-1996 and 2002-2005 and from UK in 1991-1992. One locus, at ALAD on chromosome 9, showed consistent association with blood lead across countries and evidence for multiple independent allelic effects. The most significant single nucleotide polymorphism (SNP), rs1805313 (P = 3.91 × 10(-14) for lead concentration in a meta-analysis of all data), is known to have effects on ALAD expression in blood cells but other SNPs affecting ALAD expression did not affect blood lead. Variants at 12 other loci, including ABO, showed suggestive associations (5 × 10(-6) > P > 5 × 10(-8)). Identification of genetic polymorphisms affecting blood lead reinforces the view that genetic factors, as well as environmental ones, are important in determining blood lead levels. The ways in which ALAD variation affects lead uptake or distribution are still to be determined. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  14. Synthetic Plant Defense Elicitors

    Directory of Open Access Journals (Sweden)

    Yasemin eBektas

    2015-01-01

    Full Text Available To defend themselves against invading pathogens plants utilize a complex regulatory network that coordinates extensive transcriptional and metabolic reprogramming. Although many of the key players of this immunity-associated network are known, the details of its topology and dynamics are still poorly understood. As an alternative to forward and reverse genetic studies, chemical genetics-related approaches based on bioactive small molecules have gained substantial popularity in the analysis of biological pathways and networks. Use of such molecular probes can allow researchers to access biological space that was previously inaccessible to genetic analyses due to gene redundancy or lethality of mutations. Synthetic elicitors are small drug like molecules that induce plant defense responses, but are distinct from known natural elicitors of plant immunity. While the discovery of the some synthetic elicitors had already been reported in the 1970s, recent breakthroughs in combinatorial chemical synthesis now allow for inexpensive high-throughput screens for bioactive plant defense-inducing compounds. Along with powerful reverse genetics tools and resources available for model plants and crop systems, comprehensive collections of new synthetic elicitors will likely allow plant scientists to study the intricacies of plant defense signaling pathways and networks in an unparalleled fashion. As synthetic elicitors can protect crops from diseases, without the need to be directly toxic for pathogenic organisms, they may also serve as promising alternatives to conventional biocidal pesticides, which often are harmful for the environment, farmers and consumers. Here we are discussing various types of synthetic elicitors that have been used for studies on the plant immune system, their modes-of-action as well as their application in crop protection.

  15. Characterization and biocompatibility studies of lead free X-ray shielding polymer composite for healthcare application

    Science.gov (United States)

    Singh, Anil Kumar; Singh, Rakesh Kumar; Sharma, Bhupesh; Tyagi, Ajay Kumar

    2017-09-01

    Lead based X-ray shielding systems are widely being used in healthcare and radiation processing centers to protect technicians, operators and patients from unwanted exposure to ionizing radiation. However, the use of lead is avoided mainly due to its toxic effects on human health and environment, and also discomfort due to heavier in weight. Hence, production of non-toxic, environment friendly, lead-free X-ray shielding system with less weight and good radiation shielding efficiency compared to conventional lead-based shielding systems is a challenging issue and need of the day. The objectives of present study are to develop, characterize and establish synergy of the materials making radiation shielding composition and their biocompatibility without compromising on radiation shielding efficiency and physico-mechanical attributes vis-à-vis lead based systems.

  16. Synthetic cannabinoids: new matrix addiction

    Directory of Open Access Journals (Sweden)

    Antsyborov A.V.

    2017-04-01

    Full Text Available the majority of synthetic cannabinoids (SC, belongs to the group of so-called designer drugs distributed through illegal online shopping. The first reports of this group of psychoactive substances appeared in the 70s of the last century. Today, according to various estimates, there are over 160 varieties of synthetic cannabinoids, and this figure is increasing annually due to the synthesis of new substances in the group. This group of substances is designed to «copy» the psychoactive effects of cannabis. Initially, these substances were created solely for research purposes, to study the endocannabinoid system of the person. Natural THC is a partial agonist of cannabinoid receptors. Synthetic cannabinoids are full agonists CB1R and CB2R types of cannabinoid receptors. Most countries in the world, including Russia, at the legislative level have taken restrictive measures for preventing the spread of this group of substances. In order to circumvent the legislative measures, the producers of synthetic cannabinoids regularly changing the chemical formula. Each year, an increasing number of emergency hospital admissions associated with the use of synthetic cannabinoids in the peer-reviewed literature describes the deaths directly attributable to medical complications after taking synthetic cannabinoids. Numerous studies have proven the possibility of developing psychological dependence due to the use of synthetic cannabinoids. The proposed review of the literature is presented for the purpose of organizing data in the field of synthetic cannabinoids.

  17. [Ridge preservation with synthetic nanocrystalline hydroxyapatite reduces the severity of gingival invaginations-a prospective clinical study].

    Science.gov (United States)

    Reichert, Christoph; Wenghoefer, Matthias; Kutschera, Eric; Götz, Werner; Jäger, Andreas

    2014-01-01

    Gingival invaginations develop after tooth extraction and subsequent orthodontic space closure. Aetiological factors and long-term effects of gingival invaginations on oral health are nearly unknown. In addition, preventive or therapeutic strategies are rare. This prospective clinical study employing the split mouth technique was performed to investigate the effect of extraction socket augmentation with a synthetic nanocrystalline hydroxyapatite (NanoBone(®) Artoss, Rostock, Germany) on the incidence and degree of gingival invaginations. A total of 10 orthodontic patients with need for symmetric premolar extractions offering a total of 28 extractions were included in this trial. The study plan provided one extraction site to be augmented with synthetic nanocrystalline hydroxyapatite (NanoBone(®)), the other served as control. After primary wound healing, space closure was performed under defined biomechanical conditions. After space closure was accomplished, occurrence and degree of gingival invaginations as well as probing depths of the adjacent teeth mesial and distal to the extractions were determined and dental radiographs were taken. The degree of gingival invaginations and probing depths mesial and distal of the extraction were significantly reduced on NanoBone(®) augmented extraction sites. In addition, 70% of the radiographs revealed translucent and hyperdense areas on the intervention side after space closure. Apical root resorption was found in 2 patients on both the NanoBone(®) side and the control side. Ridge preservation with NanoBone(®) appeared to reduce the severity of gingival invaginations. Further investigation on long-term effects is mandatory to eliminate the appearance of adverse effects.

  18. Study of lead pollution in air, soil and water samples of Quetta city

    International Nuclear Information System (INIS)

    Khan, M.; Khan, G.M.; Akbar, S.; Panezai, M.A.; Haq, Z.U.

    2011-01-01

    This study briefly presents the collected data of lead pollution in the environment of Quetta City in Balochistan, Pakistan. The samples were collected from different sites. The analysis of lead was carried out in underground water samples, the exhaust of different vehicles, roadside and sewage soils from selected points of Quetta City. The average discharge resulted in deposition by motorcycles (29.12 g/h), cars (44.47 g/h), wagons (176.54 g/h) and buses (141.52 g/h). The maximum deposition was 222.96 g/h from auto-rickshaws. The value for lead in smoke of different vehicles seems quite high when extrapolated to the large number of such vehicles for a longer time. The concentration of lead in roadside soil varied from 73.3 mg/kg (T and T closed colony) to 731.9 mg/kg (Sirki road bus-stop). The average content of lead in sewage soil of City Nala is 1250.6 mg/kg. The level of lead was more than WHO standards for such soils. The lead quantity in all 24 tube- well water samples, was slightly above the WHO standards (10 macro g/L).The results of this study were comparable to similar study in twin cities of Rawalpindi and islamabad. (author)

  19. Determinants of maternal and umbilical blood lead levels: a cross-sectional study, Mosul, Iraq

    Directory of Open Access Journals (Sweden)

    Al-Jomard Raghad A

    2009-03-01

    Full Text Available Abstract Background The populations who are most sensitive to lead exposure from various sources are pregnant women and their newborns. Aiming to explore the presence of correlation between maternal and cord blood lead levels and to identify potential predictors that may influence both levels, the present study has been conducted. Methods A cross-sectional study was conducted covering 350 full terms maternal-newborns pairs from Mosul maternity hospitals. Data were obtained directly from women just before delivery by the use of a detailed questionnaire form. Maternal and umbilical blood lead levels were estimated using LEADCARE® Blood Lead Testing System and Kits. Results A positive significant correlation was found between maternal and cord blood lead values (r = 0.856, p = 0.001. By backward stepwise logistic regression analysis the followings emerged as significant potential predictors of high maternal blood lead: low parity, smoking and Hb level Conclusion Study results have provided baseline data needed to be transformed to decision makers to implement measures to eliminate lead from the environment and protect future generation from its deleterious effects.

  20. Study on corrosion test techniques in lead bismuth eutectic flow. Joint research report in JFY2002

    International Nuclear Information System (INIS)

    Takahashi, Minoru; Sekimoto, Hiroshi

    2003-03-01

    The evaluation of corrosion behaviors of core and structural materials in lead bismuth eutectic is one of the key issues for the utilization of lead bismuth eutectic as a coolant of the primary loops of lead bismuth cooled fast breeder reactors (FBRs) and the intermediate heat transport media of new-type steam generators of the sodium cooled FBRs. The purpose of the present study is to establish corrosion test techniques in lead bismuth eutectic flow. The techniques of steel corrosion test and oxygen control in flowing lead bismuth eutectic, and the technologies of a lead bismuth flow test at high temperature and high velocity were developed through corrosion test using a lead bismuth flow test loop of the Tokyo Institute of Technology in JFY2002. The major results are summarized as follows: (1) Techniques of fabrication, mount and rinse of corrosion specimens, measurement method of weight loss, and SEM/EDX analysis method have been established through lead bismuth corrosion test. (2) Weight losses were measured, corrosion and lead bismuth-adhered layers and eroded parts were observed in two 1000 hr-corrosion tests, and the results were compared with each other for twelve existing steels including ODS, F82H and SUH-3. (3) An oxygen sensor made of zirconia electrolyte structurally resistant to thermal stress and thermal shock was developed and tested in the lead bismuth flow loop. Good performance has been obtained. (4) An oxygen control method by injecting argon and hydrogen mixture gas containing steam into lead bismuth was applied to the lead bismuth flow loop, and technical issues for the development of the oxygen control method were extracted. (5) Technical measures for freezing and leakage of lead bismuth in the flow loop were accumulated. (6) Technical measures for flow rate decrease/blockage due to precipitation of oxide and corrosion products in a low temperature section of the lead bismuth flow loop were accumulated. (7) Electromagnetic flow meters with MI

  1. New Bis-Pyrazolones as Potential Leads for ROS Inhibition; Environment Friendly Green Synthesis, Structural Characterization, and In Vitro Studies.

    Science.gov (United States)

    Yousuf, Sahar; Khan, Khalid Mohammed; Salar, Uzma; Jabeen, Almas; Ahmed, Shakil; Muhammad, Munira Taj; Faheem, Aisha; Perveen, Shahnaz

    2018-01-12

    Pyrazolones have identified as significant antioxidant agents and many marketed and clinically prescribed NSAIDs have pyrazolone ring as main scaffold. Keeping in consideration the antioxidant potential of pyrazolone scaffold, new bis-pyrazolones 3-30 were synthesized by a green and enviroment friendly reaction route, in which two equivalents of 1-(4-chlorophenyl)-3-methyl-1H-pyrazol-5-ol were treated with one equivalent of benzaldehyde derivatives without any catalyst. All compounds were structurally characterzied by 1H-NMR and FAB analysis. 13C-NMR of selected compounds was also recorded. All compounds gave satisfactory elemental analyses and found in good agreement with calculated values. Synthetic bis-pyrazolones 3-30 were evaluated for their oxidative burst inhibitory effect of zymosan stimulated whole blood phagocytes by using luminol enhanced chemilluminescence technique. All molecules demonstrated the potent ROS inhibition activity in the range of IC50 = 1.2 ± 0.1-48.8 ± 3.9 µM as compared to the standard ibuprofen (IC50 = 54.2 ± 9.2 µM). The purity of active compounds was checked by HPLC. This study has identified a number of non-acidic lead molecules for future research on ROS inhibitors. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  2. Synthetic Study of 2.5-D ATEM Based on Finite Element Method

    DEFF Research Database (Denmark)

    Qiang, Jianke; Zhou, Junjie; Cai, Hongzhu

    2013-01-01

    Based on the regular triangular dissection for finite element method, we implemented the forward modeling of 2.5-D airborne transient electromagnetic method. The 3-D EM field was firstly transformed into Laplace domain and after that we will apply Fourier transform to reduce the dimension from 3-D...... to 2.5-D. We can obtain the EM field solution in Laplace domain by applying finite element method. The inverse Laplace transform is applied to our solution which finally leads to the airborne EM response in time domain. In compared to the traditional method, we apply our finite element method...... to the anomalous field which can avoid the singularity problem caused by the source which can excite the anomalous EM field. The EM source can be imposed to our process by incorporate the background EM field. The computation error can be accumulated due to the large variation of EM field and it can also...

  3. Legacies of Lead in Charm City's Soil: Lessons from the Baltimore Ecosystem Study.

    Science.gov (United States)

    Schwarz, Kirsten; Pouyat, Richard V; Yesilonis, Ian

    2016-02-06

    Understanding the spatial distribution of soil lead has been a focus of the Baltimore Ecosystem Study since its inception in 1997. Through multiple research projects that span spatial scales and use different methodologies, three overarching patterns have been identified: (1) soil lead concentrations often exceed state and federal regulatory limits; (2) the variability of soil lead concentrations is high; and (3) despite multiple sources and the highly heterogeneous and patchy nature of soil lead, discernable patterns do exist. Specifically, housing age, the distance to built structures, and the distance to a major roadway are strong predictors of soil lead concentrations. Understanding what drives the spatial distribution of soil lead can inform the transition of underutilized urban space into gardens and other desirable land uses while protecting human health. A framework for management is proposed that considers three factors: (1) the level of contamination; (2) the desired land use; and (3) the community's preference in implementing the desired land use. The goal of the framework is to promote dialogue and resultant policy changes that support consistent and clear regulatory guidelines for soil lead, without which urban communities will continue to be subject to the potential for lead exposure.

  4. Effects of low level lead and cadmium on reproduction in Peromyscus leucopus and a study of lead concentration in small mammals from old orchards

    OpenAIRE

    Yocum, Susan Marie

    1988-01-01

    Lead and cadmium frequently occur together as contaminants in polluted environments such as roadsides, urban areas, mines, and smelters. Few studies have been conducted to examine the possible interactive effects these metals may have on reproduction of wild species. The first part of this study was directed toward examining the effects of low level dietary lead and cadmium on reproduction in Peromyscus Jeucopus. Two laboratory studies were conducted. Treatment with combinat...

  5. A Pilot Study of Children’s Blood Lead Levels in Mount Isa, Queensland

    Directory of Open Access Journals (Sweden)

    Donna Green

    2017-12-01

    Full Text Available Mount Isa, Queensland, is one of three Australian cities with significant lead emissions due to nonferrous mining and smelting. Unlike the two other cities with lead mines or smelters, Mount Isa currently has no system of annual, systematic, community-wide blood lead level testing; and testing rates among Indigenous children are low. In previous screenings, this group of children has been shown to have higher average blood lead levels than non-Indigenous children. The first aim of this study was to assess whether parents and children would participate in less invasive, rapid point-of-care capillary testing. The second aim was to measure blood lead levels among a range of children that roughly reflected the percentage of the Indigenous/non-Indigenous population. This pilot study is based on a convenience sample of children between the ages of 12 and 83 months who were recruited to participate by staff at a Children and Family Centre. Over three half-days, 30 children were tested using capillary blood samples and the LeadCare II Point-of-Care testing system. Rapid point-of-care capillary testing was well tolerated by the children. Of 30 children tested, 40% (n = 12 had blood lead levels ≥5 µg/dL and 10% had levels ≥10 µg/dL. The highest blood lead level measured was 17.3 µg/dL. The percentage of children with blood lead levels ≥5 µg/dL was higher among Indigenous children compared to non-Indigenous (64.2% compared to 18.8% as was the geometric mean level (6.5 (95% CI, 4.7, 9.2 versus 2.4 (95% CI, 1.8, 3.1, a statistically significant difference. Though based on a small convenience sample, this study identified 12 children (40% of the sample with blood lead levels ≥5 µg/dL. Due to historical and ongoing heavy metal emissions from mining and smelting in Mount Isa, we recommend a multi-component program of universal blood lead level testing, culturally appropriate follow-up and intervention for children who are identified with blood lead

  6. Can coastline plant species be used as biosamplers of emerging contaminants? - UV-filters and synthetic musks as case studies.

    Science.gov (United States)

    Ribeiro, H; Ramos, S; Homem, V; Santos, L

    2017-10-01

    Personal care products, an important class of emerging contaminants, have been frequently detected in different environmental matrices. Included in this category are synthetic musks compounds (SMCs) and UV-filters. Their occurrence in the coastal environment has been poorly studied. Therefore, this work aimed to verify whether five coastline plant species (Carpobrotus edulis, Cakile maritima, Medicago marina, Elymus farctus borealis-atlanticus and Euphorbia paralias) have the ability to accumulate 11 SMCs (cashmeran, celestolide, phantolide, galaxolide, tonalide, exaltolide, musk moskene, tibetene, ambrette, xylene and ketone) and 2 organic UVB filters (3-(4'-methylbenzylidene) camphor and octocrylene), functioning as biosamplers. To accomplish this task, a QuEChERS technique ("Quick, Easy, Cheap, Effective, Rugged, and Safe") was employed to extract the target compounds from the plant material collected in 15 beaches of Matosinhos and Vila Nova de Gaia (Portugal). The resulting extracts were analysed by gas chromatography-mass spectrometry. Limits of detection ranged from 0.02 ng g -1 for celestolide and tonalide to 1.32 ng g -1 for musk ambrette. The obtained recoveries were around 93% and relative standard deviation was generally less than 15%. SMCs were detected at levels ranging from 1.56 to 350 ng g -1 dw and UV-filters from 2.9 to 264 ng g -1 dw. Galaxolide and 3-(4'-methylbenzylidene) camphor were the synthetic musk and UV-filter detected in higher concentrations, respectively. Plants with higher water content accumulate better SMCs (hottentot-fig), while those with higher lipid content retain better the UV-filters (sea spurge). Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Synthetic Molecular Machines for Active Self-Assembly: Prototype Algorithms, Designs, and Experimental Study

    Science.gov (United States)

    Dabby, Nadine L.

    behaviors. This class of behaviors includes any behavior where a passive physical system simply does not have enough physical energy to perform the specified tasks in the requisite amount of time. As we will demonstrate and prove, a sufficiently expressive implementation of an "active" molecular self-assembly approach can achieve these behaviors. Using an external source of fuel solves part of the problem, so the system is not "energetically incomplete." But the programmable system also needs to have sufficient expressive power to achieve the specified behaviors. Perhaps surprisingly, some of these systems do not even require Turing completeness to be sufficiently expressive. Building on a large variety of work by other scientists in the fields of DNA nanotechnology, chemistry and reconfigurable robotics, this thesis introduces several research contributions in the context of active self-assembly. We show that simple primitives such as insertion and deletion are able to generate complex and interesting results such as the growth of a linear polymer in logarithmic time and the ability of a linear polymer to treadmill. To this end we developed a formal model for active-self assembly that is directly implementable with DNA molecules. We show that this model is computationally equivalent to a machine capable of producing strings that are stronger than regular languages and, at most, as strong as context-free grammars. This is a great advance in the theory of active self-assembly as prior models were either entirely theoretical or only implementable in the context of macro-scale robotics. We developed a chain reaction method for the autonomous exponential growth of a linear DNA polymer. Our method is based on the insertion of molecules into the assembly, which generates two new insertion sites for every initial one employed. The building of a line in logarithmic time is a first step toward building a shape in logarithmic time. We demonstrate the first construction of a synthetic

  8. Genotoxicity studies of heavy metals: lead, bismuth, indium, silver and antimony.

    Science.gov (United States)

    Asakura, Keiko; Satoh, Hiroshi; Chiba, Momoko; Okamoto, Masahide; Serizawa, Koji; Nakano, Makiko; Omae, Kazuyuki

    2009-01-01

    Many kinds of heavy metals are used in industry; thus, it is important for us to clarify their toxicity. For example, lead, which is a component of solder, is notorious for its neurotoxicity, and substitute materials have been sought for many years. Therefore, we examined the genotoxicity of lead and also those of metallic bismuth, indium, silver and antimony which are possible substitutes for lead in solder. Bacterial reverse mutation tests and chromosomal aberration tests in cultured mammalian cells were performed according to standard procedures. Antimony showed genotoxicity in both tests, and bismuth also showed positive results in the chromosomal aberration test. In contrast, lead, indium, and silver were considered to be inactive by the criteria of the present study. Although further studies are needed because of the difficulty of genotoxicity evaluation using an in vitro system, sufficient precautions should be made when antimony and bismuth are used.

  9. THERMOHALINE INSTABILITIES INSIDE STARS: A SYNTHETIC STUDY INCLUDING EXTERNAL TURBULENCE AND RADIATIVE LEVITATION

    Energy Technology Data Exchange (ETDEWEB)

    Vauclair, Sylvie; Theado, Sylvie, E-mail: sylvie.vauclair@irap.omp.eu [Universite de Toulouse, UPS-OMP and CNRS, Institut de Recherche en Astrophysique et Planetologie, 14 avenue Edouard Belin, F-31400 Toulouse (France)

    2012-07-01

    We have derived a new expression for the thermohaline mixing coefficient in stars, including the effects of radiative levitation and external turbulence, by solving Boussinesq equations in a nearly incompressible stratified fluid with a linear approximation. It is well known that radiative levitation of individual elements can lead to their accumulation in specific stellar layers. In some cases, it can induce important effects on the stellar structure. Here we confirm that this accumulation is moderated by thermohaline convection due to the resulting inverse {mu}-gradient. The new coefficient that we have derived shows that the effect of radiative accelerations on the thermohaline instability itself is small. This effect must however be checked in all computations. We also confirm that the presence of large horizontal turbulence can reduce or even suppress the thermohaline convection. These results are important as they concern all the cases of heavy element accumulation in stars. Computations of radiative diffusion must be revisited to include thermohaline convection and its consequences. It may be one of the basic reasons for the fact that the observed abundances are always smaller than those predicted by pure atomic diffusion. In any case, these processes have to compete with rotation-induced mixing, but this competition is more complex than previously thought due to their mutual interaction.

  10. Leading Short-Term Study Abroad Courses: Motivations and Outcomes for Community College Faculty

    Science.gov (United States)

    Hull, Melinda Leigh

    2013-01-01

    This case study explored faculty motivations for choosing to lead short-term study abroad courses and the personal and professional outcomes of the undertaking as reported by the faculty members themselves. This study also identified specific instances of internationalized practice in the development and implementation of the course. Three faculty…

  11. Recent studies of lead neurotoxicity in children: old metal, new questions

    Directory of Open Access Journals (Sweden)

    David C. Bellinger

    2011-09-01

    Full Text Available Many times in the history of lead toxicology the view has prevailed that „the problem” has been solved, and that exposure to lead is no longer a major public health concern. Each time, additional research has demonstrated the prematurity of this judgment. In the last decade, an extraordinary number of new studies have illustrated that „the problem” remains, and that it has dimensions never before considered. Children’s intelligence has traditionally been considered to be the most sensitive endpoint and used as the basis for risk assessment and standard setting. For IQ, the dose-effect relationship appears to be supra-linear, with greater deficits per μg/L increment below than above 100 μg/L. Recent studies have found that greater lead exposure in early childhood is also associated with a wide variety of other outcomes, with some associations evident at biomarker levels comparable to those at which IQ deficits are observed. Among these endpoints are poorer academic achievement, ADHD, conduct disorder, and antisocial behavior. In animals, early life lead exposure has been implicated in neurodegenerative disorders later in life, perhaps via epigenetic mechanisms. Studies employing neuroimaging modalities such as volumetric, diffusion tensor, and functional MRI are providing insights into the neural bases of the cognitive impairments associated with greater lead exposure. Several recent risk assessments (e.g., EFSA, JECFA have concluded that research has yet to identify a threshold level below which lead can be considered „safe”.

  12. Contribution to the study of the geophysical behaviour of lead-210 by application of alpha spectrometry

    International Nuclear Information System (INIS)

    Nezami, M.

    1965-06-01

    A study of the changes in the lead-210 contents of rain-water and of water produced by melting polar ice has required the development of a method for dosing lead-210, an α emitter. This method is 40 times more sensitive than that which measures the lead-210 by bismuth-210, a (β emitter. The first part of the report presents the study of a spectrometry using semiconductor detectors; a catalogue of a spectra shows the advantages of this method. In the second part will be found at first a new chemical separation method for polonium-210 and the results obtained with this method. The main results obtained on the geophysical behaviour of lead-210 are the following: - the monthly lead-210 and polonium-210 contents in rain water are approximately constant with time. - in the Gif-sur-Yvette region, the clean-up by 'dry fall-out' can attain 40 to 50 per cent of the total fall-out. - a study of Antarctic ice samples makes it possible to determine an annual accumulation rate equivalent to 13.8 cm of water and to show discrepancies in the periodic concentrations which correspond to the latest maxima of solar activity. - a balance is drawn up between the radon produced by the continents and the lead-210 fall-out. (author) [fr

  13. Analysis of a Study of Lead Wheel Weight Deposition and Abrasion in New Jersey.

    Science.gov (United States)

    Root, Robert A

    This paper analyzes the implications for children's health of shortcomings in the methods and results of a study of lead in the environment, "Quantity of Lead Released to the Environment in New Jersey in the Form of Motor Vehicle Wheel Weights," by the New Jersey Department of Environmental Protection (Aucott and Caldarelli, Water, Air, & Soil Pollution, 223 , 1743-1752, 2012). The study significantly understates the amount of lead deposited in New Jersey streets as 12 metric tons per year and incorrectly concludes that only 40 kg per year of the lead from wheel weights is abraded into small particles. The 2012 New Jersey Department of Environmental Protection (NJDEP) study misleads regulators and the public into believing that little toxic particulate lead from abraded wheel weights occurs on the streets of New Jersey and by implication that little occurs elsewhere in the United States, thus minimizing the potential health risk that lead wheel weights may have to our nation's children and indeed all of us.

  14. Synthetic approaches to nucleopeptides containing all four nucleobases, and nucleic acid-binding studies on a mixed-sequence nucleo-oligolysine.

    Science.gov (United States)

    Roviello, Giovanni N; Musumeci, Domenica

    2016-07-16

    In this article we describe two solid-phase synthetic routes to obtain a nucleo-oligolysine α-peptide containing all four natural nucleobases. The first one is based on the oligomerization of the nucleobase-containing monomers, easily synthesized as herein described. The second strategy has the advantage of avoiding the solution synthesis of the monomeric building blocks, leading to the final nucleopeptide by direct solid-phase couplings of the suitably protected nucleobases with the free amino groups on the growing peptide chain still anchored to the resin. Both strategies are general and can be applied to the synthesis of nucleopeptides having backbones formed by any other diamino acid moiety decorated with the four nucleobases. We also report the CD and UV studies on the hybridization properties of the obtained nucleopeptide, containing all four nucleobases on alternate lysines in the sequence, towards complementary DNA and RNA strands. The nucleo-oligolysine with a mixed-base sequence did not prove to bind complementary DNA, but was able to recognize the complementary RNA forming a complex with a higher melting temperature than that of the corresponding RNA/RNA natural duplex and comparable with that of the analogous PNA/RNA system.

  15. Study of the porosity of synthetic sandstones by nondestructive nuclear techniques

    International Nuclear Information System (INIS)

    Marques, Leonardo Carmezini

    2008-01-01

    In this paper, nuclear techniques have been used to describe structural characteristics of ceramic samples. These samples were produced to serve as simulates of sandstones and their mainly component was silica (SiO 2 ). Three sets of these samples with different characteristics were analyzed with the gamma ray transmission and the X-ray microtomography. They had the function to describe parameters as porosity point to point and total average porosity, for the transmission case, and 2D sections average porosity, total average porosity and size porous distribution for microtomography, as well as to investigate possible irregularities in bulk sample. The experimental set up for the gamma ray transmission technique consisted of: a 2 x 2 crystal NaI(Tl) detector, an 241 Am radioactive source (59.54 keV, 100 mCi), an automatic micrometric table for the sample XZ movement and standard gamma spectrometry electronics. Lead collimators with 2 mm diameter were placed on the source way out and on the detector entrance. The microtomographic measurements were done with a Skyscan system, model 1172, with a X-ray tube with 20-100 kV of voltage range and a CCD camera. Employing gamma ray transmission method was possible to obtain overall porosity values from 25.8 to 34.0 % and from 24.8 to 29.2 % for samples with parallelepiped and cylinder shape, respectively, for ceramic I set; from 58.5 to 61.0 % and from 57.1 to 61.7 % for the same geometric shape of ceramic II set. The samples analyzed by the microtomography achieved resolutions of 1.73 μm, 0.64 μm and 1.28 μm for samples of ceramic set I, II and III, respectively. This methodology provided average total porosity values from 26.6 to 29.4 %, from 48.4 to 51.0 % and from 28.2 to 30.6 % to I, II and III ceramic sets, respectively. The porous size profiles of each ceramic sample were also measured. (author)

  16. Porosity study of synthetic sandstones by non-destructive nuclear techniques

    International Nuclear Information System (INIS)

    Marques, Leonardo Carmezini

    2008-01-01

    In this paper, nuclear techniques have been used to describe structural characteristics of ceramic samples. These samples were produced to serve as simulates of sandstones and their mainly component was silica (SiO 2 ). Three sets of these samples with different characteristics were analyzed with the gamma ray transmission and the X-ray microtomography. They had the function to describe parameters as porosity point to point and total average porosity, for the transmission case, and 2D sections average porosity, total average porosity and size porous distribution for microtomography, as well as to investigate possible irregularities in bulk sample. The experimental set up for the Gamma Ray Transmission technique consisted of: a 2'' x 2'' crystal NaI(Tl) detector, an 241 Am radioactive source (59.54 keV, 100 mCi), an automatic micrometric table for the sample XZ movement and standard gamma spectrometry electronics. Lead collimators with 2 mm diameter were placed on the source way out and on the detector entrance. The microtomographic measurements were done with a Skyscan system, model 1172, with a X -ray tube with 20 - 100 kV of voltage range and a CCD camera. Employing gamma ray transmission method was possible to obtain overall porosity values from 25.8 to 34.0 % and from 24.8 to 29.2 % for samples with parallelepiped and cylinder shape, respectively, for ceramic I set; from 58.5 to 61.0 % and from 57.1 to 61.7 % for the same geometric shape of ceramic II set. The samples analyzed by the microtomography achieved resolutions of 1.73 μm, 0.64 μm and 1.28 μm for samples of ceramic set I, II and III, respectively. This methodology provided average total porosity values from 26.6 to 29.4 %, from 48.4 to 51.0 % and from 28.2 to 30.6 % to I, II and III ceramic sets, respectively. The porous size profiles of each ceramic sample were also measured. (author)

  17. Lead Pollution Remanence in an Urban River System: A multi-scale temporal and spatial study

    Directory of Open Access Journals (Sweden)

    Ayrault S.

    2013-04-01

    Full Text Available This work aims at studying the fate of sediments contaminated with tetraethyl Pb from leaded gasoline using a two-dimension upscaling approach, from a small urban subcatchment, the Orge River (900 km2 to the whole Seine River basin (64700 km2, in France. In France, the leaded gasoline reduction started in 1986 and leaded gasoline was completely banned after 2000. This work aims at assessing whether the ban of leaded gasoline is related to changes in Pb contamination sources of these river suspended sediment particles (SPM and bed sediment. Sediment cores and samples collected in the course of previous research projects of the Seine River contamination were used as temporal archives. The study of the isotopic lead ratio showed the fast decrease of the contamination of urban river suspended particulate matter due to the “gasoline” lead source from 2000 to 2011. This source mostly disappeared in the SPM from the Seine River basin that includes urban areas but also agricultural and industrial activities. Nevertheless, it is still present in the small urban catchment of the Orge River. The results on bed sediments showed a different pattern, where the “gasoline” source is still active in densely populated areas, either in the Seine River in the 20 km downstream Paris, or along the Orge River.

  18. In vivo evaluation of biofunctionalized implant surfaces with a synthetic peptide (P-15) and its impact on osseointegration. A preclinical animal study.

    Science.gov (United States)

    Schmitt, Christian M; Koepple, Markus; Moest, Tobias; Neumann, Konrad; Weisel, Tamara; Schlegel, Karl Andreas

    2016-11-01

    The overall aim of the study was to investigate a biofunctionalized implant surface with electrochemically deposition of hydroxyapatite and the synthetic peptide (P-15) and its effect on osseointegration. Three modified implant types of ANKYLOS ® C/X implants were used; (1) machined implants used as negative control (M, n = 20), (2) implants with the FRIADENT ® plus surface (grit blasted and acid-etched) used as positive control (P, n = 20), and (3) implants with a biomimetic surface consisting of hydroxyapatite and the synthetic 15 aminoacids containing peptide P-15 (BP, n = 40). The implants were randomly inserted in the mandibles of 10 beagle dogs following 4 months after tooth extraction (P1-P4). Three animals were sacrificed 2 and 7 days after implant insertion, respectively, and four animals were sacrificed 6 months post implant insertion. Bone-to-implant contacts (BICs) were analyzed via histomorphometrical analyses at five different region of interests (ROIs); two at the middle part on either side of the implant (ROI 1/4), two at the apical part of the implant at each side (ROI 2/3), and one at the tip of the implant (ROI 5). All implant surfaces showed a high level of osseointegration and osteoconductivity. The cumulative implant survival rate (CSR) was 93.8%, 100% in the M, 85% in the P, and 95% in the BP group. No statistical difference in BICs at ROI 1/4, 2/3, and 5 could be shown between implant types following 2 and 7 days of healing. BIC values increased in all groups over time. After 6 months of healing the BP group showed superiority in BIC in ROI 2/3 (73.2 ± 15.6%) compared to the P (48.3 ± 10.6%) and M group (66.3 ± 30.2%) with a significant difference between BP and P (P = 0.002). It is hypothesized, that the surface biofunctionalization improves peri-implant bone formation and remodeling, leading to an increased bone-to implant contact. However, within the limitations of the study set-up no benefit in the early phase of

  19. Synthetic prions and other human neurodegenerative proteinopathies.

    Science.gov (United States)

    Le, Nhat Tran Thanh; Narkiewicz, Joanna; Aulić, Suzana; Salzano, Giulia; Tran, Hoa Thanh; Scaini, Denis; Moda, Fabio; Giachin, Gabriele; Legname, Giuseppe

    2015-09-02

    Transmissible spongiform encephalopathies (TSE) are a heterogeneous group of neurodegenerative disorders. The common feature of these diseases is the pathological conversion of the normal cellular prion protein (PrP(C)) into a β-structure-rich conformer-termed PrP(Sc). The latter can induce a self-perpetuating process leading to amplification and spreading of pathological protein assemblies. Much evidence suggests that PrP(Sc) itself is able to recruit and misfold PrP(C) into the pathological conformation. Recent data have shown that recombinant PrP(C) can be misfolded in vitro and the resulting synthetic conformers are able to induce the conversion of PrP(C) into PrP(Sc)in vivo. In this review we describe the state-of-the-art of the body of literature in this field. In addition, we describe a cell-based assay to test synthetic prions in cells, providing further evidence that synthetic amyloids are able to template conversion of PrP into prion inclusions. Studying prions might help to understand the pathological mechanisms governing other neurodegenerative diseases. Aggregation and deposition of misfolded proteins is a common feature of several neurodegenerative disorders, such as Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis and other disorders. Although the proteins implicated in each of these diseases differ, they share a common prion mechanism. Recombinant proteins are able to aggregate in vitro into β-rich amyloid fibrils, sharing some features of the aggregates found in the brain. Several studies have reported that intracerebral inoculation of synthetic aggregates lead to unique pathology, which spread progressively to distal brain regions and reduced survival time in animals. Here, we review the prion-like features of different proteins involved in neurodegenerative disorders, such as α-synuclein, superoxide dismutase-1, amyloid-β and tau. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Generation of synthetic influent data for performing (micro) pollutant wastewater treatment modelling studies

    DEFF Research Database (Denmark)

    Snip, L. J. P.; Aymerich, I.; Flores-Alsina, X.

    2015-01-01

    considerable interest (Flores-Alsina et al., 2014, Martin and Vanrolleghem 2014). The objective of this paper is to show the usefulness of model based influent generators to reproduce (micro) pollutant influent characteristics when performing WWTP modelling studies. Using a 30000 PE WWTP as a case base, three...... different types of pharmaceuticals (antibiotic, anti-inflammatory, model stabilizer) are the selected micro-pollutant to run the study. In addition, the paper is complemented describing the influent variation of flow-rate(Q), traditional pollutants (COD, N, P) and temperature (T). Two different data sets......The use of Activated Sludge Models (ASM) (Henze et al., 2000) is constantly growing and both industry and academia are increasingly applying these tools when performing wastewater treatment plant (WWTP) engineering studies. Besides describing the behaviour of traditional pollutants such as organic...

  1. Structural Studies on Intact Clostridium botulinum Neurotoxins Complexed with Inhibitors Leading to Drug Design

    Science.gov (United States)

    2009-02-01

    TITLE:Structural Studies on Intact Clostridium botulinum Neurotoxins Complexed with Inhibitors Leading to Drug Design PRINCIPAL INVESTIGATOR: Dr...JAN 2009 4. TITLE AND SUBTITLE Structural Studies on Intact Clostridium botulinum 5a. CONTRACT NUMBER Neurotoxins Complexed with Inhibitors... Clostridium , botulinum , neurotoxin, zinc chelators, inhibitors, macromolecular crystallography, 3D structure 16. SECURITY CLASSIFICATION OF: 17

  2. The Politics of Educational Policy Studies: A Preliminary Analysis of Leading Educational Policy Journal Publications

    Science.gov (United States)

    Hardy, Ian

    2009-01-01

    This paper argues that the content, analytical approaches and institutional affiliations of authors of articles published in the latest issues of two leading educational policy studies journals provide useful insights into the contested nature of educational policy studies. The paper draws upon a selection of articles published in 2007/08 issues…

  3. Leading Schools as Living Systems: A Model of Organizational Survival--A Delphi Study

    Science.gov (United States)

    Romero, Ricardo

    2012-01-01

    Purpose: The purpose of this study was to determine the most necessary and the most feasibly practicable future leadership behaviors of the educational leader of a California Schools to Watch-Taking Center Stage middle school necessary to lead a school organization toward continued survival. Methodology: The participants in the present study were…

  4. A synthetic medical and sociological study on twins exposed by atomic bomb, 8

    International Nuclear Information System (INIS)

    Satow, Yukio; Watanabe, Shoji; Kyo, Taiichi

    1984-01-01

    The relationship between immunoglobulin (IgG, IgA, IgM) levels and the exposure status was examined in 13 enzygotic twin pairs who had been exposed to atomic bomb under the same or different conditions and who had no disease showing changes in immunoglobulin levels. The difference in immunoglobulin levels tended to be smaller between the twins exposed under the same conditions and to be larger between the twins exposed under the different conditions. This should be further studied because there were some exceptions in this study. (Namekawa, K.)

  5. STUDIES ON NATURAL AND SYNTHETIC POLYMERS FOR CONTROLLED RELEASE MATRIX TABLET OF ACECLOFENAC

    OpenAIRE

    Abhishek S. Joshi *, Deepak A. Joshi , Avinash V. Dhobale , Sandhya S. Bundel , Vijay R. Chakote, Gunesh N. Dhembre

    2018-01-01

    The present study was aimed to design new oral controlled release matrix tablets of new NSAID Aceclofenac for once a day by using 10, 15, 20 and 25% of GG:HPMC and XG:HPMC mixture in the ratio 1:1 by wet granulation method. The prepared tablets subjected to in vitro drug release studies in pH 7.4 buffer solution. All the formulation meets the pre-compression and compression characteristics. All the tablets prepared with 10, 15, 20 and 25% of HPMC: XG mixture in the ratio 1:1 fails to meet the...

  6. "But What if I Fail?" A Meta-Synthetic Study of the Conditions Supporting Teacher Innovation

    Science.gov (United States)

    Holdsworth, Sally; Maynes, Nancy

    2017-01-01

    This meta-synthesis investigates the conditions that support teacher innovation in schools. Twenty-seven articles that report on studies using a combination of qualitative and quantitative methodology were selected for this analysis. The articles were analyzed using Hargreaves's and Fullan's concept of "professional capital" as a…

  7. Studies on adsorption behaviour of Cr(VI) onto synthetic hydrous ...

    African Journals Online (AJOL)

    Hydrous stannic oxide (HSO) was synthesized in the laboratory and its systematic Cr (VI) adsorption behaviour was studied by means of batch experiments. The particle size of HSO used was in the range of 140 to 290µm. The variable parameters viz. the effects of pH, concentration of Cr (VI) and time of contact etc. are here ...

  8. The study of synthetic food dyes by positron annihilation lifetime spectroscopy.

    Science.gov (United States)

    Pivtsaev, A. A.; Razov, V. I.

    2015-06-01

    By method of positron annihilation lifetime spectroscopy (PALS), substances are food dyes were studied: E-102 (Tartrazine), E-124 (Ponso 4R), E 132 (Indigo carmine), E-133 (Brilliant Blue), E-151 (Black Shiny). They are examined for the presence of carcinogenic properties. The difference between dyes having explicit carcinogenic properties and mutagenic properties (non-explicit carcinogens) is established.

  9. The study of synthetic food dyes by positron annihilation lifetime spectroscopy

    International Nuclear Information System (INIS)

    Pivtsaev, A A; Razov, V I

    2015-01-01

    By method of positron annihilation lifetime spectroscopy (PALS), substances are food dyes were studied: E-102 (Tartrazine), E-124 (Ponso 4R), E 132 (Indigo carmine), E-133 (Brilliant Blue), E-151 (Black Shiny). They are examined for the presence of carcinogenic properties. The difference between dyes having explicit carcinogenic properties and mutagenic properties (non-explicit carcinogens) is established. (paper)

  10. Polarimetric synthetic aperture radar application for tropical peatlands classification: a case study in Siak River Transect, Riau Province, Indonesia

    Science.gov (United States)

    Novresiandi, Dandy Aditya; Nagasawa, Ryota

    2017-01-01

    Mapping spatial distributions of tropical peatlands is important for properly estimating carbon emissions and for providing information that aids in the sustainable management of tropical peatlands, particularly in Indonesia. This study evaluated the performance of phased array type L-band synthetic aperture radar (SAR) (PALSAR) dual-polarization and fully polarimetric data for tropical peatlands classification. The study area was in Siak River Transect, Riau Province, Indonesia, a rapidly developing region, where the peatland has been intensively converted mostly into oil palm plantations over the last two decades. Thus, polarimetric features derived after polarimetric decompositions, backscatter coefficients measurements, and the radar vegetation index were evaluated to classify tropical peatlands using the decision tree classifier. Overall, polarimetric features generated by the combination of dual-polarization and fully polarimetric data yielded an overall accuracy (OA) of 69% and a kappa coefficient (K) of 0.57. The integration of an additional feature, "distance to river," to the algorithm increased the OA to 76% and K to 0.66. These results indicated that the methodology in this study might serve as an efficient tool in tropical peatlands classification, especially when involving the use of L-band SAR dual-polarization and fully polarimetric data.

  11. Biosorption of lead ions by cyanobacteria Spirulina platensis: kinetics, equilibrium and thermodynamic study

    Directory of Open Access Journals (Sweden)

    Zinicovscaia Inga

    2017-12-01

    Full Text Available The potential use of dry Spirulina platensis biomass to remove lead ions from aqueous solution was investigated. Effects of various parameters such as contact time, temperature, dosage of biosorbent, initial pH, and initial concentration of lead were investigated in the batch adsorption mode. The highest lead removal of 5.7 mg/g was obtained at pH 5, biomass dosage of 0.5 g, initial lead concentration of 60 mg/L. The Langmuir and Freundlich models fit the experimental data (R2 > 0.99, while the kinetic data was best described using the pseudo second-order kinetic model (R2 > 0.99. FTIR spectra indicated that the metal removal takes place through binding to OH, C=O and P=O groups. Lead was efficiently recovered from biomass by mineral acids, while using CH3COOH and NaOH as eluents the biomass maintained high biosorption capacity during three cycles. This study demonstrates the potential of using Spirulina platensis as biosorbent to remove lead from industrial wastewater.

  12. Synthetic study on derivatives of dimeric peptide from human IgG1 hinge region

    Czech Academy of Sciences Publication Activity Database

    Niederhafner, Petr; Gut, Vladimír; Hulačová, Hana; Maloň, Petr; Slaninová, Jiřina; Hlaváček, Jan

    2006-01-01

    Roč. 12, Supplement (2006), s. 110 ISSN 1075-2617. [European Peptide Symposium /29./. 03.09.2006-08.09.2006, Gdansk] R&D Projects: GA ČR(CZ) GA203/03/1362; GA AV ČR(CZ) IAA400550614 Institutional research plan: CEZ:AV0Z40550506 Keywords : hinge region * PEG syntheses * vaccination study Subject RIV: CC - Organic Chemistry

  13. A study of bio-hybrid silsesquioxane/yeast: Biosorption and neuronal toxicity of lead.

    Science.gov (United States)

    Trama-Freitas, Bianca; Freitas, Johnattan C S; Martins, Rui C; Gando-Ferreira, Licínio M; Quinta-Ferreira, Maria Emília; Quinta-Ferreira, Rosa Maria; do Carmo, Devaney R

    2017-12-20

    Lead is a heavy metal of high impact for the environment as well as for human health, being cause of several diseases. Considering the importance of obtaining an effective treatment for lead removal, a new hybrid material was developed for sorption of Pb 2+ from aqueous solution. The effect of pH, temperature, liquid/solid ratio (g/cm 3 ) and lead concentration on the sorption capacity of yeasts chemically modified with cubic silsesquioxane (YS) was analyzed. Additionally, the toxicity of lead on the neuronal activity was also investigated in order to assess whether the damage caused by the Pb 2+ ion is reversible or not. The YS is highly promissory as sorbent of lead in high concentrations (100 and 500ppm), reaching high efficiency in short contact times (15min), and at the natural pH (4) of the Pb 2+ solution and room temperature. The best sorption obtained was 82% removal and 248mg/g with 500cm 3 /g sorbent, pH 4, room temperature and contact time of 15min. Besides, such high efficiencies are obtained with low quantities of biosorbent, when compared with other similar materials. The impact of lead on neuronal function was studied by measuring autofluorescence signals, associated with changes in cellular metabolism, at the hippocampal CA3 area in brain slices. In this toxicity tests, the effect of low concentrations of lead (1 and 3μM) on neuronal activity was evaluated. After removal of the lead, the irreversibility of the observed changes can be verified, which suggests the existence of neuronal damages. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Blood lead levels, iron metabolism gene polymorphisms and homocysteine: a gene-environment interaction study.

    Science.gov (United States)

    Kim, Kyoung-Nam; Lee, Mee-Ri; Lim, Youn-Hee; Hong, Yun-Chul

    2017-12-01

    Homocysteine has been causally associated with various adverse health outcomes. Evidence supporting the relationship between lead and homocysteine levels has been accumulating, but most prior studies have not focused on the interaction with genetic polymorphisms. From a community-based prospective cohort, we analysed 386 participants (aged 41-71 years) with information regarding blood lead and plasma homocysteine levels. Blood lead levels were measured between 2001 and 2003, and plasma homocysteine levels were measured in 2007. Interactions of lead levels with 42 genotyped single-nucleotide polymorphisms (SNPs) in five genes ( TF , HFE , CBS , BHMT and MTR ) were assessed via a 2-degree of freedom (df) joint test and a 1-df interaction test. In secondary analyses using imputation, we further assessed 58 imputed SNPs in the TF and MTHFR genes. Blood lead concentrations were positively associated with plasma homocysteine levels (p=0.0276). Six SNPs in the TF and MTR genes were screened using the 2-df joint test, and among them, three SNPs in the TF gene showed interactions with lead with respect to homocysteine levels through the 1-df interaction test (phomocysteine levels at an α-level of 0.05, but the associations did not persist after Bonferroni correction. These SNPs did not show interactions with lead levels. Blood lead levels were positively associated with plasma homocysteine levels measured 4-6 years later, and three SNPs in the TF gene modified the association. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  15. Particle yields, antiproton scaling and the average transverse momenta in high energy lead-lead collisions a model-based study

    CERN Document Server

    Guptaroy, P; De, B; Bhattacharya, D P

    2001-01-01

    The study aims at explaining the behaviour of some of the very important observables measured in the latest lead-lead collisions at CERN in the light of a variety of the sequential chain model. Calculated values, to our surprise, are in excellent agreement with the measurements, especially when the effect of cascading and rescattering is empirically introduced in the calculations of the average transverse momenta. Implications of the results are discussed. (17 refs).

  16. A study on the treatment of radioactive liquid wastes using synthetic by air intake system

    Energy Technology Data Exchange (ETDEWEB)

    Kim, T. G.; Lee, Y. H.; An, S. J.; Son, J. S.; Hong, K. P. [KAERI, Taejon (Korea, Republic of)

    2003-07-01

    In this study based on the mass transfer theory, experiments for the evaporation rates depending on various conditions were carried out through the operation of the existing Natural Evaporation Facility in KAERI. Evaporation media were made of the cotton and polyester. Air circulation in the facility was forced by exhausting fans. The evaporation rate and the decontamination factor were calculated by the result of experiment. The evaporation rate increased as the flow rate of air supply, the feed rate of liquid waste, and the temperature of supplied air increased. As for the humility of supplied air, the evaporation rate was getting higher as the humidity was getting lower. As the result of this study, operation conditions of the Natural Evaporation Facility are optimized as follows; The air temperature above 8C .deg., the air humidity below 70%, the air flow rate 1.14-1.47 m/sec, and the liquid waste feed rate 4.6l/hr.m{sup 2}. The decontamination factor and the radioactivity are 5.1x10{sup 3} and 4.7x10{sup -13}{mu}Ci/ml respectively, at the above mentioned optimum operation conditions. The air factor in the Dalton's equation for evaporation was determined from results of experiment on the temperature, the humidity, and the flow rate of supplied air as following; Eh=(0.0168+0.0141V){delta}H.

  17. A study on the treatment of radioactive liquid wastes using synthetic by air intake system

    International Nuclear Information System (INIS)

    Kim, T. G.; Lee, Y. H.; An, S. J.; Son, J. S.; Hong, K. P.

    2003-01-01

    In this study based on the mass transfer theory, experiments for the evaporation rates depending on various conditions were carried out through the operation of the existing Natural Evaporation Facility in KAERI. Evaporation media were made of the cotton and polyester. Air circulation in the facility was forced by exhausting fans. The evaporation rate and the decontamination factor were calculated by the result of experiment. The evaporation rate increased as the flow rate of air supply, the feed rate of liquid waste, and the temperature of supplied air increased. As for the humility of supplied air, the evaporation rate was getting higher as the humidity was getting lower. As the result of this study, operation conditions of the Natural Evaporation Facility are optimized as follows; The air temperature above 8C .deg., the air humidity below 70%, the air flow rate 1.14-1.47 m/sec, and the liquid waste feed rate 4.6l/hr.m 2 . The decontamination factor and the radioactivity are 5.1x10 3 and 4.7x10 -13 μCi/ml respectively, at the above mentioned optimum operation conditions. The air factor in the Dalton's equation for evaporation was determined from results of experiment on the temperature, the humidity, and the flow rate of supplied air as following; Eh=(0.0168+0.0141V)ΔH

  18. Pharmacokinetic study and bioavailability of a novel synthetic trioxane antimalarial compound 97/63 in rats.

    Science.gov (United States)

    Kushwaha, Hari Narayan; Mohan, Neel Kamal; Sharma, Ashok Kumar; Singh, Shio Kumar

    2014-01-01

    Single dose pharmacokinetics study of 97/63 (IND191710, 2004), a trioxane antimalarial developed by Central Drug Research Institute, Lucknow, India, was studied in rats following intravenous and oral administration. Serum samples were analysed by HPLC-UV assay. Separation was achieved on a RP-18 column attached with a guard using acetonitrile : phosphate buffer (70 : 30% v/v) with UV detector at wavelength 244 nm. Serum samples were extracted with n-hexane. Two-compartment model without lag time and first-order elimination rate was considered to be the best fit to explain the generated oral and intravenous data. Method was sensitive with limit of quantification of 10 ng mL(-1). Recovery was >74%. Terminal half-life and area under curve (AUC) after administering single oral (72 mg kg(-1)) and intravenous (18 mg kg(-1)) doses were 10.61 h, 10.57 h, and 1268.97 ng h mL(-1), 2025.75 ng h mL(-1), respectively. After oral dose, 97/63 was rapidly absorbed attaining maximum concentration 229.24 ng mL(-1) at 1 h. Bioavailability of 97/63 was ~16%. The lower bioavailability of drug may be due to poor solubility and first-pass metabolism and can be improved by prodrug formation of 97/63.

  19. Parameter study of 3D synthetic aperture post-beamforming procedure

    DEFF Research Database (Denmark)

    Nikolov, Svetoslav; Santén, Peter; Bjuvsten, Ola

    2006-01-01

    A method to increase the image resolution and dynamic range is to use the acquired data from several emissions (lines) and to beamform the collected RF signals treating the focal point in transmit as a virtual source of a spherical wave. The transducer is swept mechanically over the region...... of interest to scan a full volume. The same beamformation procedure is applied both in the azimuth and the elevation planes. This paper presents a study of the influence of the position of the transmit focus on the image resolution, the signal-to-noise ratio and penetration depth. The investigation is based...... depths. 100 different positions of the transmit focus are investigated. For every transmit focus the image is beamformed and evaluated. Finally the gain in signal-to-noise ratio and penetration depth are investigated experimentally for the setup, with which the best resolution is achieved. Simulations...

  20. Synthetic Studies on Quassinoids: Total Synthesis and Biological Evaluation of (+)-Des-D-chaparrinone.

    Science.gov (United States)

    Grieco, Paul A.; Speake, Jason D.

    1998-08-21

    A total synthesis of des-D-chaparrinone (2), which lacks the ring D delta-lactone of (-)-chaparrinone (1) has been developed. The synthesis commences with the known, readily available tricyclic ketone 3 (R = Me). Elaboration of the configuration at C(5) followed by resolution of 6 employing 2(R),3(R)-2,3-butanediol gave rise to 9. Installation of the ring C functionality provided 15 which was transformed into tricyclic diketone 25. Introduction of the ring A functional groups afforded 29, which upon exposure to aluminum trichloride and sodium iodide gave rise directly to (+)-des-D-chaparrinone (2). Biological studies revealed that (+)-2 was devoid of any solid tumor activity.

  1. Synthetic and Biological Studies of Sesquiterpene Polygodial: Activity of 9-Epipolygodial Against Drug Resistant Cancer Cells

    Science.gov (United States)

    Dasari, Ramesh; De Carvalho, Annelise; Medellin, Derek C.; Middleton, Kelsey N.; Hague, Frédéric; Volmar, Marie N. M.; Frolova, Liliya V.; Rossato, Mateus F.; De La Chapa, Jorge J.; Dybdal-Hargreaves, Nicholas F.; Pillai, Akshita; Mathieu, Véronique; Rogelj, Snezna; Gonzales, Cara B.; Calixto, João B.; Evidente, Antonio; Gautier, Mathieu; Munirathinam, Gnanasekar; Glass, Rainer; Burth, Patricia; Pelly, Stephen C.; van Otterlo, Willem A. L.; Kiss, Robert; Kornienko, Alexander

    2015-01-01

    Polygodial, a terpenenoid dialdehyde isolated from Polygonum hydropiper L., is a known TRPV1 agonist. In this investigation a series of polygodial analogues were prepared and investigated for TRPV1 agonistic and anticancer activities. These experiments led to the identification of 9-epipolygodial, possessing antiproliferative potency significantly exceeding that of polygodial. Epipolygodial maintained potency against apoptosis-resistant cancer cells as well as those displaying the MDR phenotype. In addition, a chemical feasibility for the previously proposed mechanism of action of polygodial, involving the Paal-Knorr pyrrole formation with a lysine residue on the target protein, was demonstrated through the synthesis of a stable polygodial pyrrole derivative. These studies reveal rich chemical and biological properties associated with polygodial and its direct derivatives. They should inspire further work in this area aimed at the development of new pharmacological agents or exploration of novel mechanisms of covalent modification of biological molecules with natural products. PMID:26434977

  2. Quantitative structure-toxicity relationship study of some natural and synthetic coumarins using retention parameters

    Directory of Open Access Journals (Sweden)

    Rabtti El Hadi M.A.

    2012-01-01

    Full Text Available Four lipophilicity descriptors (RM0, b, C0, PC1 for twelve coumarine derivatives were determined by reversed-phase thin-layer chromatography in order to analyze which descriptor best describes the lipophilicity of coumarines investigated. Moreover, possible chemical toxicity of coumarins, expressed as the probability of a compound to cause organ-specific health effects, was calculated using ACD/Tox Suite program. The quantitative relationships between toxicity and molecular descriptors, including experimentally determined lipophilicity descriptors obtained in current study, were investigated using partial least square regression. The best models were obtained for kidney and liver health effects. Quantitative structure-toxicity relationship models revealed the importance of electric polarization descriptors, size descriptors and lipophilicity descriptors. Obtained models were used for the selection of the structural features of the compounds that are significantly affecting their absorption, distribution, metabolism, excretion, and toxicity. [Acknowledgements. This work has been supported by the Ministry of Education and Science of Serbia, Grant 172017.

  3. Experimental and theoretical spectroscopic studies of dye modification in synthetic Maya Blue pigment

    Science.gov (United States)

    Reza, Layra; Manciu, Felicia; Ramirez, Alejandra; Chianelli, Russell

    2009-03-01

    Maya pigments are hybrid organic/inorganic materials with multiple technology applications that possess unprecedented stability with respect to harsh environment conditions. In this investigation, we address the question of how the organic indigo dye modifies as it binds to the inorganic palygorskite clay to form a pigment similar to Maya Blue after a heating treatment is applied. Both infrared and Raman spectroscopic data demonstrate the disappearance of nitrogen-hydrogen (N-H) bonding, as the indigo molecule incorporates into the inorganic palygorskite material. This effect suggests a transformation of the dye from indigo to dehydroindigo. Furthermore, the Raman and infrared absorption results demonstrate partial elimination of the selection rules for the centrosymmetric indigo, which provides further evidence for this conversion. Theoretical spectroscopic studies are also addressed in this investigation to confirm the transformation of the dye into dehydroindigo.

  4. Raman spectroscopic study of synthetic pyrope-grossular garnets: structural implications

    Science.gov (United States)

    Du, Wei; Han, Baofu; Clark, Simon Martin; Wang, Yichuan; Liu, Xi

    2017-06-01

    A study of the effect of substitution of Mg and Ca in garnet solid solution (Grtss) was carried out using Raman spectroscopy to probe changes to the crystal lattice. The garnet solid solutions with composition changing along pyrope (Py; Mg3Al2Si3O12) and grossular (Gr; Ca3Al2Si3O12) binary were synthesized from glass at 6 GPa and 1400 °C and a second series of Grtss with composition Py40Gr60 were synthesized at 6 GPa but different temperatures from 1000 to 1400 °C. Raman mode assignments were made based on a comparison with the two end members pyrope and grossular, which show consistent result with literature study on single crystals data. The correlation between the Raman mode frequencies and compositional changes along the pyrope-grossular binary suggests a two-mode behavior for Mg and Ca cations in the garnet structure. The full widths at half-maximum of selected Raman modes increase on moving away from the end members and are about double the end-member values in the mid-position, where the frequencies closely linearly change with composition. The frequencies of the translational modes of the SiO4 tetrahedron (T(SiO4)) show large deviations from linearity indicating a strong kinematic coupling with the translational modes of the Ca and Mg cations. The anomalies in T(SiO4) are linked to mixing unit cell volume, suggesting that the nonlinear mixing volume behavior along the pyrope-grossular binary is related to the resistance of the Si-O bond to expansion and compression, which is caused by substitution of Mg and Ca cations in the dodecahedral sites. Annealing temperature also shows effect on Raman mode frequencies, but the main factor controlling the changes in mode frequencies along pyrope-grossular binary is composition.

  5. Raman spectroscopic study of synthetic pyrope-grossular garnets: structural implications

    Science.gov (United States)

    Du, Wei; Han, Baofu; Clark, Simon Martin; Wang, Yichuan; Liu, Xi

    2018-02-01

    A study of the effect of substitution of Mg and Ca in garnet solid solution (Grtss) was carried out using Raman spectroscopy to probe changes to the crystal lattice. The garnet solid solutions with composition changing along pyrope (Py; Mg3Al2Si3O12) and grossular (Gr; Ca3Al2Si3O12) binary were synthesized from glass at 6 GPa and 1400 °C and a second series of Grtss with composition Py40Gr60 were synthesized at 6 GPa but different temperatures from 1000 to 1400 °C. Raman mode assignments were made based on a comparison with the two end members pyrope and grossular, which show consistent result with literature study on single crystals data. The correlation between the Raman mode frequencies and compositional changes along the pyrope-grossular binary suggests a two-mode behavior for Mg and Ca cations in the garnet structure. The full widths at half-maximum of selected Raman modes increase on moving away from the end members and are about double the end-member values in the mid-position, where the frequencies closely linearly change with composition. The frequencies of the translational modes of the SiO4 tetrahedron (T(SiO4)) show large deviations from linearity indicating a strong kinematic coupling with the translational modes of the Ca and Mg cations. The anomalies in T(SiO4) are linked to mixing unit cell volume, suggesting that the nonlinear mixing volume behavior along the pyrope-grossular binary is related to the resistance of the Si-O bond to expansion and compression, which is caused by substitution of Mg and Ca cations in the dodecahedral sites. Annealing temperature also shows effect on Raman mode frequencies, but the main factor controlling the changes in mode frequencies along pyrope-grossular binary is composition.

  6. One century of studies on lead poisoning in papers published in La Medicina del Lavoro.

    Science.gov (United States)

    Alessio, L; Cortesi, I; Materzanini, P; Barenghi, M

    2000-09-01

    One century of papers published in the Italian journal of occupational medicine, La Medicina del Lavoro, shows clearly that the study of lead is an exemplary topic for occupational physicians, enabling them to observe the evolution of research in the field of occupational health. The numerous pathological features of lead poisoning, doctors' successive therapeutic responses, and their gradual development of preventive techniques, form a paradigm that has subsequently been applied to all other fields of industrial toxicology. The evolution of the study of lead poisoning during this century is a complete example in the field of occupational toxicology for medical students: it will stimulate them in applying both clinical and preventive knowledge in the field of industrial toxicology. Copyright 2000 Wiley-Liss, Inc.

  7. [Study of the efficacy of low-dose synthetic ACTH therapy without tapering to treat West syndrome].

    Science.gov (United States)

    Kodama, Kazuo; Omata, Taku; Arai, Hidee; Tanabe, Yuzo

    2016-05-01

    We evaluated the effectiveness of synthetic adrenocorticotropic hormone (ACTH) therapy without tapering in treating patients with West syndrome. Forty-four patients with cryptogenic (n = 7) or symptomatic (n = 37) West syndrome were treated with synthetic ACTH therapy between 2003 and 2012. The synthetic ACTH dosage was 0.0125 mg/kg/day administered daily for 2 weeks and then stopped without a tapering period. The initial effectiveness, long-term seizure outcome, and adverse effects were examined. During synthetic ACTH therapy, epileptic spasms disappeared in 37 of 44 patients (84.1%) and hypsarrhythmia on electroencephalography disappeared in 42 of 44 patients (95.5%). The average number of synthetic ACTH injections needed to achieve spasm control in these 37 patients was 5.8. Long-term seizure outcomes were assessed in 31 patients followed up for longer than half a year after synthetic ACTH therapy. Nine (29.0%) of these patients experienced recurrence of epileptic spasms, with a mean interval to recurrence of 2.4 months. Overall, 12 patients (38.7%) experienced various types of seizures other than spasms with a mean interval to recurrence of 8.0 months. Although adverse effects such as hypertension, infection, and mild brain shrinkage were noted in 13 patients (29.5%), no severe adverse effects were observed. These results are comparable to those of other reports on the initial effectiveness and long-term seizure control following synthetic ACTH therapy, and suggest that administration without tapering is reasonable to treat patients with West syndrome.

  8. Removal of methylparaben from synthetic aqueous solutions using polyacrylonitrile beads: kinetic and equilibrium studies.

    Science.gov (United States)

    Forte, Maurizio; Mita, Luigi; Perrone, Rosa; Rossi, Sergio; Argirò, Mario; Mita, Damiano Gustavo; Guida, Marco; Portaccio, Marianna; Godievargova, Tzonka; Ivanov, Yavour; Tamer, Mahmoud T; Omer, Ahmed M; Mohy Eldin, Mohamed S

    2017-01-01

    The removal of methylparaben (MP), a well-known endocrine disruptor, from aqueous solutions using polyacrylonitrile (PAN) beads has been studied under batch conditions, at room temperature and at different initial MP concentrations. The kinetic and equilibrium results have been analyzed. Kinetic modeling analysis has been carried out with three different types of adsorption models: pseudo-first-order, pseudo-second-order, and Elovich model. Kinetic data analysis indicated that the adsorption was a second-order process. The MP adsorption by PAN was also quantitatively evaluated by using the equilibrium adsorption isotherm models of Langmuir, Freundlich, Dubinin-Radushkevich (D-R), and Temkin and the applicability of the respective isotherm equations has been compared through the correlation coefficients. Adsorption data resulted well fitted by the Freundlich isotherm model. Data of MP adsorption have also been used to test different adsorption diffusion models. The diffusion rate equations inside particulate of Dumwald-Wagner and the intraparticle diffusion model have been used to calculate the diffusion rate. The actual rate-controlling step involved in the MB adsorption process was determined. The kinetic expression by Boyd gave the right indications. All together, our results indicate that PAN beads are a useful tool to remediate water bodies polluted by endocrine disruptors.

  9. Synthesis, characterization and computational study of the newly synthetized sulfonamide molecule

    Science.gov (United States)

    Murthy, P. Krishna; Suneetha, V.; Armaković, Stevan; Armaković, Sanja J.; Suchetan, P. A.; Giri, L.; Rao, R. Sreenivasa

    2018-02-01

    A new compound N-(2,5-dimethyl-4-nitrophenyl)-4-methylbenzenesulfonamide (NDMPMBS) has been derived from 2,5-dimethyl-4-nitroaniline and 4-methylbenzene-1-sulfonyl chloride. Structure was characterized by SCXRD studies and spectroscopic tools. Compound crystallized in the monoclinic crystal system with P21/c space group a = 10.0549, b = 18.967, c = 8.3087, β = 103.18 and Z = 4. Type and nature of intermolecular interaction in crystal state investigated by 3D-Hirshfeld surface and 2D-finger print plots revealed that title compound stabilized by several interactions. The structural and electronic properties of title compound have been calculated at DFT/B3LYP/6-311G++(d,p) level of theory. Computationally obtained spectral data was compared with experimental results, showing excellent mutual agreement. Assignment of each vibrational wave number was done on the basis of potential energy distribution (PED). Investigation of local reactivity descriptors encompassed visualization of molecular electrostatic potential (MEP) and average local ionization energy (ALIE) surfaces, visualization of Fukui functions, natural bond order (NBO) analysis, bond dissociation energies for hydrogen abstraction (H-BDE) and radial distribution functions (RDF) after molecular dynamics (MD) simulations. MD simulations were also used in order to investigate interaction of NDMPMBS molecule with 1WKR and 3ETT proteins protein.

  10. Electron microscopy studies of natural and synthetic zeolites impregnated with uranyl dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Acosta, Dwight R.; T-Olguin, Maria; Solache, Marcos; Bosch, Pedro; Bulbulian, Silvia [Universidad Nacional Autonoma de Mexico, Mexico City (Mexico). Inst. de Fisica; Asomoza, Max [Instituto Nacional de Investigaciones Nucleares, Mexico City (Mexico). Dept. de Quimica Nuclear

    1995-09-01

    Full text. The use of Y zeolite and erionite to remove uranyl dioxide ions from aqueous solution is focussed on catalysis and energy transfer problems but it can be oriented to recovery uranyl dioxide ions, among other radioactive compounds. The samples impregnated with uranyl dioxide at several concentrations and contact times were studied using conventional, high resolution and scanning electron microscopy in order to detect changes as consequence of contact with a radioactive material and to verify mechanical stability of zeolites. Also X ray diffraction, thermal analysis, neutron activation were used to characterize the samples at several steps of treatment. The crystallinity of zeolites was maintained only when using dilute uranyl nitrate solution (up to 0.0100 N for y zeolite and 0.0300 N for erionite). The samples impregnated with highest nitrate concentrations partially lost their crystallinity. From selected area electron diffraction pattern, lattice parameter variations were detected and from high resolution electron microscopy localization of uranyl ions in and on zeolite structure was determined. Surface modification in zeolites was observed by scanning electron microscopy just for samples with long contact time with radioactive solutions. (author)

  11. An Insight into the Pharmacophores of Phosphodiesterase-5 Inhibitors from Synthetic and Crystal Structural Studies

    Energy Technology Data Exchange (ETDEWEB)

    Chen,G.; Wang, H.; Robinson, H.; Cai, J.; Wan, Y.; Ke, H.

    2008-01-01

    Selective inhibitors of cyclic nucleotide phosphodiesterase-5 (PDE5) have been used as drugs for treatment of male erectile dysfunction and pulmonary hypertension. An insight into the pharmacophores of PDE5 inhibitors is essential for development of second generation of PDE5 inhibitors, but has not been completely illustrated. Here we report the synthesis of a new class of the sildenafil derivatives and a crystal structure of the PDE5 catalytic domain in complex with 5-(2-ethoxy-5-(sulfamoyl)-3-thienyl)-1-methyl-3-propyl-1, 6-dihydro-7H-pyrazolo[4, 3-d]pyrimidin-7-one (12). Inhibitor 12 induces conformational change of the H-loop (residues 660-683), which is different from any of the known PDE5 structures. The pyrazolopyrimidinone groups of 12 and sildenafil are well superimposed, but their sulfonamide groups show a positional difference of as much as 1.5 Angstroms . The structure-activity analysis suggests that a small hydrophobic pocket and the H-loop of PDE5 are important for the inhibitor affinity, in addition to two common elements for binding of almost all the PDE inhibitors: the stack against the phenylalanine and the hydrogen bond with the invariant glutamine. However, the PDE5-12 structure does not provide a full explanation to affinity changes of the inhibitors. Thus alternatives such as conformational change of the M-loop are open and further structural study is required.

  12. Crystal structures, in-silico study and anti-microbial potential of synthetic monocarbonyl curcuminoids

    Science.gov (United States)

    Ud Din, Zia; Serrano, N. F. G.; Ademi, Kastriot; Sousa, C. P.; Deflon, Victor Marcelo; Maia, Pedro Ivo da Silva; Rodrigues-Filho, Edson

    2017-09-01

    In this work the screening of 20 unsymmetrical chalcone and curcuminoids analogues in regard of their antimicrobial properties was conducted. Electron donating groups in the aromatic rings in the chalcone and curcuminoid derivatives produced higher antimicrobial effect. Compounds 1, 9 and 15 exhibited good activity against Escherichia coli and Staphylococcus aureus. These compounds were further evaluated against nine micro-organisms of pathological interest. Pharmmaper was used for target fishing of compounds against important bacterial targets. Molecular Docking helped to verify the results of these compounds against the selected bacterial target D-alanyl-D-alanine carboxypeptidase (PDB ID: 1PW1). The crystal structure of ligand and docked conformers in the active site of 1PW1 were analyzed. As a result structure-activity relationships are proposed. Structures of compounds 14 and 16 were obtained through single crystals X-ray diffraction studies. Compound 14 crystallizes in monoclinic space group P21/c with unit cell dimensions a = 13.1293(3) Å, b = 17.5364(4) Å, c = 15.1433(3) Å, β = 95.6440(10), V = 3469.70(13) Å3 and Z = 8. Compound 16 crystallizes in triclinic space group Pī with unit cell dimensions a = 6.8226(4) Å, b = 7.2256(4) Å, c = 18.1235(12) Å, β = 87.322(4), V = 850.57(9) Å3 and Z = 2.

  13. An experimental approach to the study of the rheology behaviour of synthetic bone calcium phosphate cements

    Energy Technology Data Exchange (ETDEWEB)

    Friberg, J.; Fernandez, E.; Sarda, S.; Nilsson, M.; Ginebra, M.P.; Planell, J.A. [Universidad Politecnica de Catalunya, Barcelona (Spain). Dept. of Materials Science and Metallurgical Engineering; Martinez, S. [Barcelona Univ. (Spain). Mineralogia i Recursos Minerals

    2001-07-01

    Calcium phosphate cements were developed to fit surgical needs in biomedical fields such as odontology or traumatology. Nowadays, a broad field of new applications have been found for this kind of materials. Drug delivery systems, tissue-engineering scaffolds and osteoporotic bone filling applications are some of the new fields that are being benefited with these materials. Looking at both, commercial and new experimental calcium phosphate cements it is found that {alpha}-tricalcium phosphate is the main reactive powder responsible for the setting and the hardening of the cement. Thus, it is important to know how {alpha}-tricalcium phosphate affects injectability of these cements. The aim of this study was to investigate the rheological behaviour of {alpha}-tricalcium phosphate slurries in order to know how the cement injectability should be modified. Factors such as liquid to powder ratio, particle size of the main reactive powder and the addition of dispersants have been considered. The results showed that viscosity decreased when particle size of reactant was increased and when liquid to powder ratio was increased. It was also found that a minimum of viscosity exists at an optimum value of the weight percentage of dispersant. (orig.)

  14. Better primary stability with porous titanium particles than with bone particles in cemented impaction grafting: An in vitro study in synthetic acetabula

    NARCIS (Netherlands)

    Walschot, L.H.B.; Aquarius, R.; Schreurs, B.W.; Buma, P.; Verdonschot, Nicolaas Jacobus Joseph

    2013-01-01

    Aims Impaction bone grafting creates new bone stock after hip joint replacement. Utilizing a synthetic bone substitute instead of bone might increase primary stability and is not associated with graft shortage and pathogen transmission. This study compares the initial stability of a graft layer of

  15. Designing Undergraduate-Level Organic Chemistry Instructional Problems: Seven Ideas from a Problem-Solving Study of Practicing Synthetic Organic Chemists

    Science.gov (United States)

    Raker, Jeffrey R.; Towns, Marcy H.

    2012-01-01

    The development of curricular problems based on the practice of synthetic organic chemistry has not been explored in the literature. Such problems have broadly been hypothesized to promote student persistence and interest in STEM fields. This study reports seven ideas about how practice-based problems can be developed for sophomore-level organic…

  16. Kinase activity and specificity assay using synthetic peptides.

    Science.gov (United States)

    Wu, Xu Na; Schulze, Waltraud X

    2015-01-01

    Phosphorylation of substrate proteins by protein kinases can lead to activation or inactivation of signaling pathways or metabolic processes. Precise understanding of activity and specificity of protein kinases are important questions in characterization of kinase functions. Here, we describe a procedure to study kinase activity and specificity using kinase-GFP complexes purified from plant material and synthetic peptides as substrates. Magnetic GFP beads allow purifying receptor-like kinase-GFP complexes from microsomal fractions. Kinase-GFP complexes are then incubated with ATP and the synthetic peptides for kinase reaction. Phosphorylation of substrate peptides is then identified and quantified by mass spectrometry.

  17. Comparative Study on Performance and Organic Fouling of ZrO2 Ceramic Membranes in Ultrafiltration of Synthetic Water and Wastewater Treatment Plant Effluent

    KAUST Repository

    Li, Cen

    2011-07-01

    Adsorption of organic matter on ceramic membrane can lead to hydraulic-irreversible fouling, which decreases the permeate flux and the cost-efficiency of membrane devices. In order to optimize the filtration process, detailed information is necessary about the organic fouling mechanisms on ceramic membranes. In this study, dead-end filtration experiments of both synthetic water and secondary effluent from a wastewater treatment plant (WWTP) were conducted on a ZrO2 ceramic membrane. The experiment results of synthetic water showed that humic acid (HA) was able to be adsorbed by the ZrO2 membrane and cause permeate flux decline; and that HA-tryptophan mixture, at the same DOC level, promoted the filtration flux decline; DOC removal in the case of HA-tryptophan was lower than that of HA alone. It seems that hydrophilic organic matter with low molecular weight have some specific contribution to the organic fouling of the ZrO2 membrane. The results also suggest that tryptophan molecules were preferentially adsorbed on the membrane at the beginning, exposing their hydrophobic sides which might further adsorb HA from the feed water. During the filtration of WWTP effluent, protein-like substances (mainly tryptophan-like) were also preferentially adsorbed on the membrane compared with humic-like ones in the initial few cycles of filtration. More humic-like substances were adsorbed in the following filtration cycles due to the increase of membrane hydrophobicity. A significant rise in hydraulic-irreversible flux decline was obtained by decreasing pH from near pHpzc to below pHpzc of the membrane. It suggests that a positively charged surface is preferred for HA adsorption. Ionic strength increase did not affect the filtration of HA, but it lessened the hydraulic-irreversible flux decline of HA-tryptophan filtration. The adsorption of HA-tryptophan can be attributed to outersphere interaction while HA adsorption is mainly caused by inner-sphere interaction. The results of

  18. Association between blood lead and blood pressure: a population-based study in Brazilian adults.

    Science.gov (United States)

    Almeida Lopes, Ana Carolina Bertin de; Silbergeld, Ellen Kovner; Navas-Acien, Ana; Zamoiski, Rachel; Martins, Airton da Cunha; Camargo, Alissana Ester Iakmiu; Urbano, Mariana Ragassi; Mesas, Arthur Eumann; Paoliello, Monica Maria Bastos

    2017-03-14

    Environmental lead exposure among adults may increase blood pressure and elevate the risk of hypertension. The availability of data on blood lead levels (BLL) in adult Brazilian population is scarce and population-based studies are important for screening the population exposure and also to evaluate associations with adverse health effects. The goal of this study was to examine the association of BLL with blood pressure and hypertension in a population-based study in a city in Southern Brazil. A total of 948 adults, aged 40 years or older, were randomly selected. Information on socioeconomic, dietary, lifestyle and occupational background was obtained by orally administered household interviews. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured according to the guidelines VI Brazilian Guidelines on Hypertension. BLL were measured by inductively coupled plasma mass spectrometry technique. Multiple linear and logistic regression models were performed to evaluate associations of BLL with SBP and DBP, and with the chance of hypertension and of elevated SBP and DBP. The geometric mean of BLL was 1.97 μg/dL (95%CI:1.90-2.04 μg/dL). After multivariable adjustment, participants in the quartile 4 of blood lead presented 0.06 mm/Hg (95%CI, 0.04-0.09) average difference in DBP comparing with those in quartile 1. Participants in the 90th percentile of blood lead distribution had 0.07 mmHg (95% CI, 0.03 to 0.11) higher DBP compared with those participants in the 10th percentile of blood lead. The adjusted OR for hypertension was 2.54 (95% CI, 1.17-5.53), comparing the highest to the lowest blood lead quartiles. Compared with participants in the 10th percentile of blood lead, participants in the 90th percentile presented higher OR for hypertension (OR: 2.77; 95% CI, 1.41 to 5.46). At low concentrations, BLL were positively associated with DBP and with the odds for hypertension in adults aged 40 or older. It is important to enforce lead

  19. Forces affecting employment dynamics in Drenthe; Case study in a leading rural region in the Netherlands

    NARCIS (Netherlands)

    Terluin, I.J.; Post, J.H.; Wisselink, A.J.; Overbeek, M.M.M.

    1999-01-01

    In this report the focus is on employment dynamics in Drenthe since the beginning of the 1980s. This study is part of an EU wide research project on employment development in leading and lagging rural regions of the EU. Total employment in Drenthe increased by 24,500 jobs or with over 20% in the

  20. Transport of lead and diesel fuel through a peat soil near Juneau, AK: a pilot study.

    Science.gov (United States)

    Julian Deiss; Carl Byers; Dave Clover; Dave D' Amore; Alan Love; Malcolm A. Menzies; J. Powell; Todd M. Walter

    2004-01-01

    A set of peat column experiments was used to determine the transport potential of lead (Pb) and diesel range organics (DRO) in palustrine slope wetlands near Juneau, AK. This project is important to southeast Alaskan communities because limited land resources are forcing development of regional wetlands. This study was instigated by concerns that proposed modifications...

  1. Experimental Study of Rheological Properties and Oil Displacement Efficiency in Oilfields for a Synthetic Hydrophobically Modified Polymer.

    Science.gov (United States)

    Liu, Pengcheng; Mu, Zhenbao; Wang, Chao; Wang, Yanling

    2017-08-18

    In a previous study, we developed a synthetic hydrophobically modified hydroxyethyl cellulose (HEC) using bromododecane (BD), which we denote as BD-HMHEC. In this work, we continually investigate the rheological properties and its oil displacement efficiency in PuTao well area in Daqing oilfields, China. Results show that BD-HMHEC solution has good viscosification, thermal-resistance, salt-tolerance, shear resistance, and acid/alkali resistance. The storage modulus (G') and the loose modulus (G") of the BD-HMHEC solutions increase significantly with increasing BD-HMHEC concentration, and the solution becomes viscoelastic at a sufficiently high BD-HMHEC concentration. The core flooding results showed BD-HMHEC flooding improves oil recovery by 7-14% in comparison with HEC flooding at concentrations of 4,000 mg/L under equivalent conditions. Moreover, BD-HMHEC flooding improves oil recovery by 7-8% after conducting water and hydrolyzed polyacrylamide (HPAM) flooding. The oil displacement mechanism of BD-HMHEC solutions is discussed based on a visual evaluation. The results indicate that BD-HMHEC flooding is a feasible means for improving oil recovery after water/HPAM flooding.

  2. Polypyrrole-coated magnetic nanoparticles as an efficient adsorbent for RB19 synthetic textile dye: Removal and kinetic study.

    Science.gov (United States)

    Shanehsaz, Maryam; Seidi, Shahram; Ghorbani, Yousefali; Shoja, Seyed Mohammad Reza; Rouhani, Shohre

    2015-01-01

    The present work deals with the first attempt to study the removal of synthetic textile dye, reactive blue 19 (RB19), using the magnetic Fe3O4 nanoparticles modified by pyrrole (PPy@Fe3O4 MNPs) as an efficient adsorbent. The nanoadsorbent was synthesized using chemical co-precipitation. Scanning electron microscopy and FT-IR were used to characterize nanoparticles. Factors affecting the dye adsorption including the pH of the dye solution, amount of adsorbent and contact time were also further investigated. Sorption of the RB19 on PPy@Fe3O4 MNPs reached to equilibrium at contact time less than 10 min and fitted well to the Langmuir adsorption model with a maximum adsorption capacity of 112.36 mg g(-1). Experiments for adsorption kinetic were carried out and the data fitted well according to a pseudo-second-order kinetic model. Moreover, the MNPs were recovered with over than 90% efficiency using methanol as elution agent. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. A phase I safety and pharmacokinetic study of ATX-101: injectable, synthetic deoxycholic acid for submental contouring.

    Science.gov (United States)

    Walker, Patricia; Fellmann, Jere; Lizzul, Paul F

    2015-03-01

    ATX-101 (deoxycholic acid [DCA] injection) is a proprietary formulation of pure synthetic DCA. When injected into subcutaneous fat, ATX-101 results in focal adipocytolysis, the targeted destruction of fat cells. ATX-101 is undergoing investigation as an injectable drug for contouring the submental area by reducing submental fat (SMF). The purpose of this study was to evaluate the safety and pharmacokinetics (PK) of the maximal therapeutic dose of ATX-101 (100 mg total dose). Following PK evaluation of endogenous DCA, subjects (N=24) received subcutaneous injections of ATX-101 (2 mg/cm2, with or without 0.9% benzyl alcohol) into SMF; PK evaluation was repeated periodically over 24 hours. Endogenous DCA plasma concentrations measured prior to injection were highly variable within and between subjects. Similarly, following ATX-101 injection, DCA plasma concentrations were highly variable, peaked rapidly, and returned to the range observed for endogenous values by 24 hours postdose. All subjects experienced at least 1 adverse event (AE). No death, serious AE, or AE-related discontinuations occurred. The majority of AEs were transient, associated with the area treated, and of mild or moderate severity. No clinically significant changes were reported for laboratory test results, vital signs, or Holter electrocardiograms postdosing. These data support the favorable safety and efficacy observations of ATX-101 as an injectable drug to reduce SMF.

  4. Biological and biochemical studies on Biomphalaria alexandrina snails, treated with low concentrations of certain molluscicides (synthetic and of plant origin).

    Science.gov (United States)

    Abdel Kader, Ahmed; Hamdi, Salwa A H; Rawi, Sayed M

    2005-12-01

    The effect of low concentrations of different synthetic and natural mollusciciding agents may introduce to fresh water environment on reproduction and biochemical aspects of Biomphalaria alexandrina was studied. Different mollusciciding agents (copper sulphate, Bayluscide, Uccmaluscide, Agave filifera & A. attenuate) inhibited egg production, induced marked increased the percent of abnormal laid eggs and induced marked reduction in their hatchability. The maximal reductions in egg hatchability resulted with Bayluscide (0.0%) and Uccmaluscide (18%), A. filifera (21%) and A. attenuata (15%). All the antimolluscal materials caused a successful killing effect against miracidia and cercariae of Schistosoma mansoni. CuSo4, Bayluscide and Uccmaluscide killed 40% of the exposed miracidia and 50% of cercariae after an hour exposure. The plants sublethal concentration killed 100% of cercariae and miracidia after 6 hours exposure. Water leaving behaviour among the exposed snails was noticed especially during the first three weeks, showing maximal percentage (60%) after one week of exposure to Bayluscide. A general decrease in the activity of alkaline phosphatase (ALP) especially with Bayluscide (48.4%) and in acetylcholine esterase activity in the haemolymph especially on applying plant molluscicide A. filifera (50.8%) was noticed. Transaminases showed marked elevations in activities during the 1st three weeks, then began to drop (ASAT: 61.5%, with Bayluscide & ALAT: 50.8% with Uccmaluscide). The results reflect the effect of the metabolic disorders on life, egg laying, egg hatchability, hepatic cells damages, lack of smooth transmission at nerve junction, loss of muscular coordination and convulsions, then snails' death.

  5. A spectroscopic and computational study of the singlet and triplet excited states of synthetic β-functionalized chlorins

    International Nuclear Information System (INIS)

    Brueckner, Christian; McCarthy, Jason R.; Daniell, Heather W.; Pendon, Zeus D.; Ilagan, Robielyn P.; Francis, Tasha M.; Ren Lei; Birge, Robert R.; Frank, Harry A.

    2003-01-01

    This paper presents a comparative investigation of the absorption, fluorescence, electron paramagnetic resonance (EPR), and transient triplet-triplet absorption spectroscopic properties and triplet state dynamics of two functionalized, synthetic, meso-phenylchlorins. The chromophores investigated are the novel 2-hydroxy-3-oxa-5,10,15,20-tetrakisphenylchlorin (3) and the known 2,3-dioxo-5,10,15,20-tetrakisphenylchlorin (4). In these chromophores, one peripheral -CH-CH- bond of the parent porphyrin meso-tetrakisphenylporphyrin (TPP, 1) was formally replaced by a -CH(OH)O- (lactol) or a β-diketone moiety. The spectroscopic data are compared with results from investigations on the parent porphyrin TPP studied here and the parent chlorin 5,10,15,20-tetrakisphenylchlorin (TPC, 2) from the literature. The spectroscopic observables are examined both qualitatively within the framework of the four orbital model and quantitatively using MNDO-PSDCI methods. The results delineate the role of β-lactol and β-dicarbonyl moieties in controlling the electronic and spectroscopic properties of these chromophores. This investigation serves as the foundation from which to derive a general understanding of the effects of β-functionalization on the electronic properties of chlorin-type chromophores. This knowledge is required for the design and understanding of long-wavelength absorbing and fluorescing chromophores to be used in light harvesting systems and photomedicine

  6. Enhanced heavy oil recovery for carbonate reservoirs integrating cross-well seismic–a synthetic Wafra case study

    KAUST Repository

    Katterbauer, Klemens

    2015-07-14

    Heavy oil recovery has been a major focus in the oil and gas industry to counter the rapid depletion of conventional reservoirs. Various techniques for enhancing the recovery of heavy oil were developed and pilot-tested, with steam drive techniques proven in most circumstances to be successful and economically viable. The Wafra field in Saudi Arabia is at the forefront of utilizing steam recovery for carbonate heavy oil reservoirs in the Middle East. With growing injection volumes, tracking the steam evolution within the reservoir and characterizing the formation, especially in terms of its porosity and permeability heterogeneity, are key objectives for sound economic decisions and enhanced production forecasts. We have developed an integrated reservoir history matching framework using ensemble based techniques incorporating seismic data for enhancing reservoir characterization and improving history matches. Examining the performance on a synthetic field study of the Wafra field, we could demonstrate the improved characterization of the reservoir formation, determining more accurately the position of the steam chambers and obtaining more reliable forecasts of the reservoir’s recovery potential. History matching results are fairly robust even for noise levels up to 30%. The results demonstrate the potential of the integration of full-waveform seismic data for steam drive reservoir characterization and increased recovery efficiency.

  7. In vivo distribution and excretion studies and in vitro blood studies on the kinetics of lead-203 in beagle dogs

    Energy Technology Data Exchange (ETDEWEB)

    Coombs, Mark A. [Rochester Univ., NY (United States). Dept. of Radiation Biology and Biophysics

    1980-01-01

    The distribution of carrier free lead-203 between plasma and cells of canine blood in vitro was measured. Activity in the plasma decreased to less than 5% of the initial blood activity during the first 15 min and then exponentially with a half time of 160 min. Incubation in cell free plasma before addition to whole blood transformed the isotope, decreasing the amount subsequently associated with cells. In animal studies, activity was measured in plasma, blood cells, urine, and feces after exposure to lead-203. In one group, the animals were exposed by intravenous injection of dilute citric acid solutions of isotope. In a second group, carrier free isotope which had been transformed by incubation in plasma was injected intravenously. The kinetics of the distribution of the isotope differed between the two experimental groups. After injection of the transformed lead, the lead-203 content of the blood cell fraction rose from 10% of the dose at 5 min to 21% to 43% at 13 h. The red cell activity after injection of citric acid solutions of lead-203 remained between 50 and 60% of the dose from 5 min to 12 h post exposure. Excretion of lead in the urine during the first day after injection of transformed lead ranged from 5 to 45% of the dose, while that of citric acid solutions of lead was between 1 and 2%. Linear compartmental models for distribution of the isotope were developed for both in vitro and in vivo experimental systems. In three additional experiments, animals were exposed to lead-203 extravascularly. In one, using a dilute citric acid solution of the isotope, plasma activity resembled that observed after intravenous injection, suggesting that isotope was transformed by extravascular fluids before reaching the circulation. In the two remaining experiments the animals were exposed to lead-203 by gavage. The results suggest that lead absorbed from the gut may have been transformed before reaching the circulation. (ERB)

  8. Study on the Activation of Scheelite and Wolframite by Lead Nitrate

    Directory of Open Access Journals (Sweden)

    Gang Zhao

    2015-04-01

    Full Text Available The activation of scheelite and wolframite by lead nitrate with benzohydroxamic acid (BHA as collector was investigated by means of micro flotation test, zeta potential measurement, X-ray photoelectron spectroscopy (XPS analyses and density functional theory (DFT calculation. The flotation results confirmed that the addition of lead nitrate can markedly enhance the recovery of scheelite and wolframite. In the zeta potential curves obvious positive shifts were observed with the presence of lead nitrate. Lead was detected on mineral surface in microscopic analysis and the survey XP spectra. Both the electrokinetic study and XPS analyses indicated that lead ion can be adsorbed onto mineral surface. In DFT calculation, the coordination model of BHA with metal hydroxyl ions (Ca(OH+, Mn(OH+, Fe(OH+ and Pb(OH+ was simulated and their binding energy were also calculated. The calculated results revealed that the binding ability of BHA and Pb(OH+ is the strongest, indicating that BHA can preferentially coordinate with Pb ion compared with Ca, Mn and Fe ions.

  9. Biosorption of cadmium (II) and lead (II) from aqueous solutions using mushrooms: A comparative study

    Energy Technology Data Exchange (ETDEWEB)

    Vimala, R., E-mail: vimararagu@yahoo.co.in [School of Biotechnology, Chemical and Biomedical Engineering, VIT University, Vellore 632014, Tamil Nadu (India); Das, Nilanjana [School of Biotechnology, Chemical and Biomedical Engineering, VIT University, Vellore 632014, Tamil Nadu (India)

    2009-08-30

    Sorption capacity of oyster mushroom (Pleurotus platypus), button mushroom (Agaricus bisporus) and milky mushroom (Calocybe indica) were evaluated on biosorption of heavy metals, viz. cadmium (II) and lead (II) from aqueous solutions. The optimum sorption conditions were studied for each metal separately. The desired pH of the aqueous solution was found to be 6.0 for the removal of cadmium (II) and 5.0 for removal of lead (II) for all the mushrooms. The percent removal of both the metals was found to increase with the increase in biosorbent dosage and contact time. The fitness of the biosorption data for Langmuir and Freundlich adsorption models was investigated. It was found that biosorption of cadmium (II) and lead (II) ions onto the biomass of the three mushrooms were better suitable to Langmuir than Freundlich adsorption model. P. platypus showed the highest metal uptake potential for cadmium (q{sub max} 34.96 mg/g) whereas A. bisporus exhibited maximum potential for lead (q{sub max} 33.78 mg/g). Milky mushroom showed the lowest metal uptake capacity for both the metals. The present data confirms that mushrooms may be used as efficient biosorbent for the removal of cadmium (II) and lead (II) ions from aqueous solution.

  10. Biosorption of cadmium (II) and lead (II) from aqueous solutions using mushrooms: A comparative study

    International Nuclear Information System (INIS)

    Vimala, R.; Das, Nilanjana

    2009-01-01

    Sorption capacity of oyster mushroom (Pleurotus platypus), button mushroom (Agaricus bisporus) and milky mushroom (Calocybe indica) were evaluated on biosorption of heavy metals, viz. cadmium (II) and lead (II) from aqueous solutions. The optimum sorption conditions were studied for each metal separately. The desired pH of the aqueous solution was found to be 6.0 for the removal of cadmium (II) and 5.0 for removal of lead (II) for all the mushrooms. The percent removal of both the metals was found to increase with the increase in biosorbent dosage and contact time. The fitness of the biosorption data for Langmuir and Freundlich adsorption models was investigated. It was found that biosorption of cadmium (II) and lead (II) ions onto the biomass of the three mushrooms were better suitable to Langmuir than Freundlich adsorption model. P. platypus showed the highest metal uptake potential for cadmium (q max 34.96 mg/g) whereas A. bisporus exhibited maximum potential for lead (q max 33.78 mg/g). Milky mushroom showed the lowest metal uptake capacity for both the metals. The present data confirms that mushrooms may be used as efficient biosorbent for the removal of cadmium (II) and lead (II) ions from aqueous solution.

  11. An XPS study of the adsorption of lead on goethite (α-FeOOH)

    Science.gov (United States)

    Abdel-Samad, Hesham; Watson, Philip R.

    1998-10-01

    The adsorption behavior of divalent metal ions on amphoteric surface hydroxyl groups of metal oxides is an important factor in the transport of subsurface environmental pollutants. We have studied the adsorption of lead ions from aqueous solution on the surface of the mineral goethite (α-FeOOH) as a function of pH and adsorbate concentration in 0.1 M NaNO 3 solution. Results obtained from the dried surface by X-ray photoelectron spectroscopy (XPS) are in good agreement with data from spectrophotometric analysis of lead ions remaining in the supernatant liquid. Lead adsorption as a function of pH shows an adsorption edge near pH 6 and maximizes by pH 7.5. The surface atomic Pb/Fe ratio at saturation as measured by XPS is 0.93 leading to an apparent high adsorption site density of 14.2 sites/nm 2. A characteristic low binding energy (BE) XPS feature is present in the Pb 4f XPS signal in the pH range 6-8. Comparison with literature predictions of the speciation of lead at a goethite surface suggests that this XPS feature is perhaps associated with a FeOPb + complex. At high Pb(II) concentrations some polynuclear complexes probably form. They may be responsible for the high site density value which, while crystallographically possible, is much higher than values reported by others working at lower Pb concentrations.

  12. Processing Mineralogy Study on Lead and Zinc Oxide Ore in Sichuan

    Directory of Open Access Journals (Sweden)

    Mei Yang

    2016-04-01

    Full Text Available The processing mineralogy characteristics of an oxidized lead-zinc ore from Sichuan were studied systematically using numerous modern instruments. Results showed that lead and zinc oxide content in the ore exceeded the minimum industrial grade, and also included a relatively high concentration of silver and iron. This ore is composed of many different minerals. Major zinc-containing minerals include sphalerite, hemimorphite, smithsonite, hydrozincite, zinc-containing baileychlore, and zinc-containing dolomite and calcite. Lead-containing minerals are primarily galena and cerussite with small amounts of dechenite, cesaronite, anglesite, limonite and coronadite. Gangue minerals include dolomite and calcite. Dissemination size for the main minerals ranges from medium (0.04 mm to fine (0.02 mm. All the valuable minerals are well liberated, including galena, sphalerite, cerussite, calamine, and smithsonite. However, the dissemination relationships are complex. Lead is concentrated mainly in galena and cerussite, while zinc occurs primarily in sphalerite, calamine, and smithsonite. The theoretical recovery for lead and zinc were estimated at 72% and 67%, respectively.

  13. A Feasibility Study of Lead Free Solders for Level 1 Packaging Applications

    DEFF Research Database (Denmark)

    Chidambaram, Vivek; Hald, John; Hattel, Jesper Henri

    2009-01-01

    An attempt has been made to determine the lead free ternary combinations that satisfied the solidification requirement for a solder used in level 1 packaging applications, using the CALPHAD approach. The segregation profiles of the promising candidates were analyzed after scrutinizing the equilib......An attempt has been made to determine the lead free ternary combinations that satisfied the solidification requirement for a solder used in level 1 packaging applications, using the CALPHAD approach. The segregation profiles of the promising candidates were analyzed after scrutinizing...... the equilibrium calculations by Scheil solidification simulations and optimization. A feasibility study has been carried out for the replacement of high-lead-containing solders with the focus on surface tension, natural radius of curvature, oxidation resistance, intermetallic compound formation, and environmental...

  14. An Influence Study of Hydrogen Evolution Characteristics on the Negative Strap Corrosion of Lead Acid Battery

    Directory of Open Access Journals (Sweden)

    Zhong Guobin

    2015-01-01

    Full Text Available Negative strap corrosion is an important reason for the failure of valve regulated lead acid battery. This paper selected the Pb-Sb alloy material and Pb-Sn alloy material, made an investigation on the negative corrosion resistance and hydrogen evolution of these two alloy materials by scanning electron microscope analysis, metallographic analysis, chemical study and linear sweep voltammetry, and discussed the influence of lead alloy hydrogen evolution on the negative strap corrosion. The results showed that the hydrogen evolution reaction rates of the alloys had an impact on the corrosion areas with the maximum thickness of the alloys and the depth of corrosion layers. Greater hydrogen evolution reaction rate can lead to shorter distance between the corrosion area with the maximum thickness and the liquid level; whereas the greater corrosion layer thickness can bring aggravated risk of negative strap corrosion failure.

  15. Micro-analytical study of interactions between oil and lead compounds in paintings

    International Nuclear Information System (INIS)

    Cotte, M.; Checroun, E.; Susini, J.; Walter, P.

    2007-01-01

    Oil paintings are complex hybrid materials, made of organic binders associated with inorganic minerals, susceptible to evolving over centuries. In particular, interactions of oil with lead compounds may give rise to the formation of lead soap aggregates, so-called protrusions. This phenomenon is studied here via X-ray and FTIR micro-analysis of an ancient painting dated from 1610. In complement, the synthesis of modern preparations, reconstructed from ancient recipes was assessed. Molecular and atomic images are obtained by combining synchrotron-based FTIR and X-ray fluorescence microscopies. Protrusions are identified in both ancient and modern samples, more particularly, in the ground layer of the paintings, below the colored layer. These observations imply that lead oxide, introduced as a siccative and not as a pigment, may be the element mainly responsible for the protrusions formation, and that this degradation may appear very rapidly on paintings. (orig.)

  16. US Competitiveness in Synthetic Biology.

    Science.gov (United States)

    Gronvall, Gigi Kwik

    2015-01-01

    Synthetic biology is an emerging technical field that aims to make biology easier to engineer; the field has applications in strategically important sectors for the US economy. While the United States currently leads in synthetic biology R&D, other nations are heavily investing in order to boost their economies, which will inevitably diminish the US leadership position. This outcome is not entirely negative--additional investments will expand markets--but it is critical that the US government take steps to remain competitive: There are applications from which the US population and economy may benefit; there are specific applications with importance for national defense; and US technical leadership will ensure that US experts have a leading role in synthetic biology governance, regulation, and oversight. Measures to increase competitiveness in S&T generally are broadly applicable for synthetic biology and should be pursued. However, the US government will also need to take action on fundamental issues that will affect the field's development, such as countering anti-GMO (genetically modified organism) sentiments and anti-GMO legislation. The United States should maintain its regulatory approach so that it is the product that is regulated, not the method used to create a product. At the same time, the United States needs to ensure that the regulatory framework is updated so that synthetic biology products do not fall into regulatory gaps. Finally, the United States needs to pay close attention to how synthetic biology applications may be governed internationally, such as through the Nagoya Protocol of the Convention on Biological Diversity, so that beneficial applications may be realized.

  17. Numerical study of a 50 kA current lead using bulk high temperature superconductors

    International Nuclear Information System (INIS)

    Heller, R.

    1993-06-01

    Based on the design of the 30 kA current lead with a low temperature superconductor (LTSC) forseen for the test of a superconducting pulsed model coil (POLO model coil) in the test facility TOSKA at KfK, a 50 kA current lead for the future test of a model coil for the International Thermonuclear Experimental Reactor ITER in the TOSKA facility was proposed resulting in a helium mass flow rate normalized to the current of 0.055 g/(s-kA) at 50 kA resp. of 0.015 g/(s-kA) at zero current. In this paper, the possibility of the use of High Temperature Superconductors (HTSC) for high current carrying current leads cooled by forced flow supercritical helium has been investigated in order to study the capabilities. The current lead behaviour has been theoretically studied under different conditions: zero current operation, nominal current (50 kA) operation, extended current (70 kA) operation, and safety behaviour (loss of helium mass flow). Two design cases which differ in the current sharing and critical temperatures of the HTSC have been investigated in order to look on the amount of helium mass flow reduction. The result is that the reduction of mass flow rate will be 50% at zero current and about 10 to 20% at 50 kA for the two cases. The transient behaviour of the HTSC lead differs considerably from the one of the LTSC lead due to the high electrical resisitivity of the HTSC. (orig.)

  18. A phase 1 pharmacokinetic study of ATX-101: serum lipids and adipokines following synthetic deoxycholic acid injections.

    Science.gov (United States)

    Walker, Patricia; Lee, Daniel

    2015-03-01

    ATX-101 (deoxycholic acid injection, Kythera Biopharmaceuticals, Inc.) is a proprietary formulation of pure synthetic deoxycholic acid (DCA). It is undergoing clinical investigation as an injectable drug for contouring the submental area by reducing submental fat (SMF). When injected into subcutaneous fat, ATX-101 causes focal adipocytolysis, the targeted destruction of fat cells. This phase 1 study evaluated the safety, pharmacokinetics (PK), and pharmacodynamic effects of ATX-101 (100-mg total dose). Following PK evaluation of baseline endogenous DCA, lipids, and adipokines in the initial stage of the study (samples collected at hours 0.25, 0.5, 1, 1.5, 2, 4, 6, 12, 15.5, and 24.5), 10 subjects received subcutaneous injections of ATX-101 into abdominal fat. PK evaluation of DCA, lipids, and adipokines was repeated in the second phase of the study. After ATX-101 injections, plasma concentration of DCA increased transiently, reached a maximum plasma concentration rapidly, and returned to endogenous concentrations within 12 h postdose. ATX-101 injection was not associated with any clinically meaningful changes in systemic concentrations of total cholesterol, total triglycerides, free fatty acids, C-reactive protein, or interleukin-6. Adverse events were mild in severity, transient, and showed a temporal relationship to dosing. This study demonstrated favorable safety and PK profiles, and no clinically meaningful changes in DCA, lipids, and proinflammatory cytokines following subcutaneous injection of ATX-101. Our results support continued clinical investigation of ATX-101 as an injectable drug to reduce SMF. © 2015 Wiley Periodicals, Inc.

  19. Structural Studies on Intact Clostridium Botulinum Neurotoxins Complexed with Inhibitors Leading to Drug Design

    Science.gov (United States)

    2006-02-01

    structure1. Introduction Tetanus neurotoxin (TeNT) produced by Clostridium tetani and the seven antigenically distinct botulinum neurotoxins (BoNT/A-G...2-0011 TITLE: Structural Studies on Intact Clostridium Botulinum Neurotoxins Complexed with Inhibitors Leading to Drug...DATES COVERED (From - To) 28 Jan 2005 – 27 Jan 2006 4. TITLE AND SUBTITLE Structural Studies on Intact Clostridium Botulinum Neurotoxins Complexed

  20. Surface deformation measured with interferometric synthetic aperture radar: Case studies of basin and range and Garlock-San Andreas fault

    Science.gov (United States)

    Greene, Fernando

    Interferometric Synthetic Aperture Radar (InSAR) and Global Positioning System (GPS) is widely used to detect ground deformation from varieties of geophysical origins. However, most studies lack the spatial and temporal resolutions to better characterize such observations. The purpose of this research is to use multi-track satellite radar imagery to generate time series to study and monitor vertical ground deformation over large regions such as the Nevada portion of the Basin and Range Province and the western end of the Mojave Desert. We developed an innovative method to remove horizontal movements from InSAR line-of-sight (LOS) observations using a GPS velocity field and subsequently combine the multi-track imagery resulting in one single high spatial resolution map of observed vertical crustal and surface movements. By implementing this technique we detect vertical deformation signals with short and intermediate wavelength signals associated to tectonic processes such as interseismic and postseismic deformation. In Central Nevada Seismic Belt we detect in three independent orbits a broad area of uplift that confirms results of previous studies that associate the origin of this signal to post-seimic deformation of the historic earthquakes at this region. In south-central Nevada we detect several valleys that show a gradual eastward tilt of the valley floors due to deep geodynamical processes. The valleys located at the eastern side of Ruby Mountains show a range decrease that could indicate uplift related to magma intrusion or post-seismic deformation due to older, unrecognized earthquakes. In the Big Bend segment in southern California we detect vertical uplift as expected by mechanical models of interseismic deformation. Additionaly all our velocity maps reveal small wavelength deformation signals of anthropogenic origin.

  1. Synthetic Scenarios from CMIP5 Model Simulations for Climate Change Impact Assessments in Managed Ecosystems and Water Resources: Case Study in South Asian Countries

    Science.gov (United States)

    Anandhi, A.; Omani, N.; Chaubey, I.; Horton, R.; Bader, D.; Nanjundiah, R. S.

    2017-01-01

    Increasing population, urbanization, and associated demand for food production compounded by climate change and variability have important implications for the managed ecosystems and water resources of a region. This is particularly true for south Asia, which supports one quarter of the global population, half of whom live below the poverty line. This region is largely dependent on monsoon precipitation for water. Given the limited resources of the developing countries in this region, the objective of our study was to empirically explore climate change in south Asia up to the year 2099 using monthly simulations from 35 global climate models (GCMs) participating in the fifth phase of the Climate Model Inter-comparison Project (CMIP5) for two future emission scenarios (representative concentration pathways RCP4.5 and RCP8.5) and provide a wide range of potential climate change outcomes. This was carried out using a three-step procedure: calculating the mean annual, monsoon, and non-monsoon precipitation and temperatures; estimating the percent change from historical conditions; and developing scenario funnels and synthetic scenarios. This methodology was applied for the entire south Asia region; however, the percent change information generated at 1.5deg grid scale can be used to generate scenarios at finer spatial scales. Our results showed a high variability in the future change in precipitation (-23% to 52%, maximum in the non-monsoon season) and temperature (0.8% to 2.1%) in the region. Temperatures in the region consistently increased, especially in the Himalayan region, which could have impacts including a faster retreat of glaciers and increased floods. It could also change rivers from perennial to seasonal, leading to significant challenges in water management. Increasing temperatures could further stress groundwater reservoirs, leading to withdrawal rates that become even more unsustainable. The high precipitation variability (with higher propensity for

  2. Occupational lead exposure among automotive garage workers – a case study for Jimma town, Ethiopia

    Directory of Open Access Journals (Sweden)

    Adela Yalemsew

    2012-07-01

    Full Text Available Abstract Background In Ethiopia, although there are numerous small-scale and medium industries which use lead-based raw materials that may pose health risks to workers, there are no workplace regulations for lead exposure. Moreover, there are no studies carried out on the blood lead levels (BLLs of workers or on the contribution of common workplace practices to lead poisoning. Method A cross-sectional study on the BLLs of 45 automotive garage workers and 40 non-garage workers was carried out in the town of Jimma, Ethiopia. In addition to BLL analysis, data on some risk factors such as smoking, and chewing ‘khat’ (the leaves of Catha adulis were gathered through structured questionnaires and interviews and data analysis was performed using SPSS (version 16. The t-test was used to compare mean BLLs of study groups. The analysis of variance (ANOVA, Kruskal-Wallis, Pearson chi-square and odds ratio tests were used to investigate the associations between specific job type, smoking and/or ‘khat’ chewing, service years and occurrence of non-specific symptoms with BLLs. Results The mean BLL of the automotive-garage workers was found to be significantly greater than that of the controls. The BLLs of all the lead-exposed individuals were found to be over 10 μg/dL, and 53% of them had BLLs ranging 12 – 20 μg/dL, with the remaining 47% having over 20 μg/dL. The BLL of the workers increased with the duration of working in an automotive garage. Individuals involved in manual car painting comprise a larger percentage (58% of those with the highest BLLs (≥ 20 μg/dL. Lead accumulation in individuals who chew ‘khat’ in the work place was found to be faster than in those who are not used to chewing ‘khat’. ‘Khat’ is an evergreen shrub native to tropical East Africa, with dark green opposite leaves which are chewed when fresh for their stimulating effects. Conclusion The findings of the study have clearly demonstrated that the

  3. Potential of Opuntia ficus-indica for air pollution biomonitoring: a lead isotopic study.

    Science.gov (United States)

    El Hayek, Eliane; El Samrani, Antoine; Lartiges, Bruno; Kazpard, Veronique; Benoit, Mathieu; Munoz, Marguerite

    2015-11-01

    Opuntia ficus-indica (Ofi) is a long-domesticated cactus that is widespread throughout arid and semiarid regions. Ofi is grown for both its fruits and edible cladodes, which are flattened photosynthetic stems. Young cladodes develop from mother cladodes, thus forming series of cladodes of different ages. Therefore, successive cladodes may hold some potential for biomonitoring over several years the local atmospheric pollution. In this study, cladodes, roots, dust deposited onto the cladodes, and soil samples were collected in the vicinity of three heavily polluted sites, i.e., a fertilizer industry, the road side of a highway, and mine tailings. The lead content was analyzed using atomic absorption spectroscopy (AAS) and inductively coupled plasma-mass spectrometry (ICP-MS). Scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM-EDX) was used to characterize the cladode surfaces and the nature of dust deposit, and the lead isotopes were analyzed to identify the origin of Pb. The results show that (i) Ofi readily bioaccumulates Pb, (ii) the lead isotopic composition of cladodes evidences a foliar pathway of lead into Ofi and identifies the relative contributions of local Pb sources, and (iii) an evolution of air quality is recorded with successive cladodes, which makes Ofi a potential biomonitor to be used in environmental and health studies.

  4. FTIR imaging in diffusion studies: CO2 and H2O in a synthetic sector-zoned beryl

    Directory of Open Access Journals (Sweden)

    Giancarlo eDella Ventura

    2015-06-01

    Full Text Available In this work we investigate the strongly inhomogeneous distribution of CO2 and H2O in a synthetic beryl having a peculiar hourglass zoning of Cr due to the crystal growth. The sample was treated at 800°C, 500 MPa, in a CO2-rich atmosphere. High-resolution FESEM images revealed that the hourglass boundary is not correlated to physical discontinuities, at least at the scale of tens of nanometers. Polarized FPA-FTIR imaging, on the other side, revealed that the chemical zoning acts as a fast pathway for carbon dioxide diffusion, a feature never observed so far in minerals. The hourglass zone boundary may be thus considered as a structural defect possibly due to the mismatch induced by the different growth rates of each sector. High-resolution synchrotron-light FTIR imaging, in addition, also allows enhancement of CO2 diffusion along the hourglass boundary to be distinguished from diffusion along fractures in the grain. Therefore, FTIR imaging provides evidence that different diffusion mechanisms may locally combine, suggesting that the distribution of the target molecules needs to be be carefully characterized in experimental studies. This piece of information is mandatory when the study is aimed at extracting diffusion coefficients from analytical profiles. Combination of TOF-SIMS and FPA data shows a significant depletion of type II H2O along the hourglass boundary, indicating that water diffusion could be controlled by the distribution of alkali cations within channels, coupled to a plug effect of CO2.

  5. Plant synthetic biology.

    Science.gov (United States)

    Liu, Wusheng; Stewart, C Neal

    2015-05-01

    Plant synthetic biology is an emerging field that combines engineering principles with plant biology toward the design and production of new devices. This emerging field should play an important role in future agriculture for traditional crop improvement, but also in enabling novel bioproduction in plants. In this review we discuss the design cycles of synthetic biology as well as key engineering principles, genetic parts, and computational tools that can be utilized in plant synthetic biology. Some pioneering examples are offered as a demonstration of how synthetic biology can be used to modify plants for specific purposes. These include synthetic sensors, synthetic metabolic pathways, and synthetic genomes. We also speculate about the future of synthetic biology of plants. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Synthetic antifreeze peptide

    OpenAIRE

    1991-01-01

    A synthetic antifreeze peptide and a synthetic gene coding for the antifreeze peptide have been produced. The antifreeze peptide has a greater number of repeating amino acid sequences than is present in the native antifreeze peptides from winter flounder upon which the synthetic antifreeze peptide was modeled. Each repeating amino acid sequence has two polar amino acid residues which are spaced a controlled distance apart so that the antifreeze peptide may inhibit ice formation. The synthetic...

  7. Mobile phone use, blood lead levels, and attention deficit hyperactivity symptoms in children: a longitudinal study.

    Directory of Open Access Journals (Sweden)

    Yoon-Hwan Byun

    Full Text Available BACKGROUND: Concerns have developed for the possible negative health effects of radiofrequency electromagnetic field (RF-EMF exposure to children's brains. The purpose of this longitudinal study was to investigate the association between mobile phone use and symptoms of Attention Deficit Hyperactivity Disorder (ADHD considering the modifying effect of lead exposure. METHODS: A total of 2,422 children at 27 elementary schools in 10 Korean cities were examined and followed up 2 years later. Parents or guardians were administered a questionnaire including the Korean version of the ADHD rating scale and questions about mobile phone use, as well as socio-demographic factors. The ADHD symptom risk for mobile phone use was estimated at two time points using logistic regression and combined over 2 years using the generalized estimating equation model with repeatedly measured variables of mobile phone use, blood lead, and ADHD symptoms, adjusted for covariates. RESULTS: The ADHD symptom risk associated with mobile phone use for voice calls but the association was limited to children exposed to relatively high lead. CONCLUSIONS: The results suggest that simultaneous exposure to lead and RF from mobile phone use was associated with increased ADHD symptom risk, although possible reverse causality could not be ruled out.

  8. [Blood lead levels during pregnancy in th the newborn period. Study of the population of Bari].

    Science.gov (United States)

    Carbone, R; Laforgia, N; Crollo, E; Mautone, A; Iolascon, A

    1998-01-01

    Blood lead levels during pregnancy and in neonates immediately after birth have been evaluated, showing higher values in mothers compared to neonates (5.81 +/- 3.05 vs 4.87 +/- 3.60 micrograms/100 ml) and a positive correlation between maternal and neonatal levels (r = 0.82). On the basis of the results derived from the population examined, it has been observed that 6% of newborns have blood lead levels higher than 10 micrograms/100 ml a value recently identified by the Centers for Disease Control (CDC, Atlanta, USA) as a limit for toxicity in children. Moreover, neonatal Pb levels were higher than those found in infants from 6 to 12 months (4.87 +/- 3.60 vs 2.24 +/- 0.54 micrograms/100 ml). During the first week of life there is a steady decrease of blood lead levels, together with increasing renal lead excretion. This study was carried out at the "Dipartimento di Biomedicina dell'Età Evolutiva" University of Bari, southern Italy.

  9. Mobile Phone Use, Blood Lead Levels, and Attention Deficit Hyperactivity Symptoms in Children: A Longitudinal Study

    Science.gov (United States)

    Byun, Yoon-Hwan; Ha, Mina; Kwon, Ho-Jang; Hong, Yun-Chul; Leem, Jong-Han; Sakong, Joon; Kim, Su Young; Lee, Chul Gab; Kang, Dongmug; Choi, Hyung-Do; Kim, Nam

    2013-01-01

    Background Concerns have developed for the possible negative health effects of radiofrequency electromagnetic field (RF-EMF) exposure to children’s brains. The purpose of this longitudinal study was to investigate the association between mobile phone use and symptoms of Attention Deficit Hyperactivity Disorder (ADHD) considering the modifying effect of lead exposure. Methods A total of 2,422 children at 27 elementary schools in 10 Korean cities were examined and followed up 2 years later. Parents or guardians were administered a questionnaire including the Korean version of the ADHD rating scale and questions about mobile phone use, as well as socio-demographic factors. The ADHD symptom risk for mobile phone use was estimated at two time points using logistic regression and combined over 2 years using the generalized estimating equation model with repeatedly measured variables of mobile phone use, blood lead, and ADHD symptoms, adjusted for covariates. Results The ADHD symptom risk associated with mobile phone use for voice calls but the association was limited to children exposed to relatively high lead. Conclusions The results suggest that simultaneous exposure to lead and RF from mobile phone use was associated with increased ADHD symptom risk, although possible reverse causality could not be ruled out. PMID:23555766

  10. Environmental factors predicting blood lead levels in pregnant women in the UK: the ALSPAC study.

    Science.gov (United States)

    Taylor, Caroline M; Golding, Jean; Hibbeln, Joseph; Emond, Alan M

    2013-01-01

    Lead is a widespread environmental toxin. The behaviour and academic performance of children can be adversely affected even at low blood lead levels (BLL) of 5-10 µg/dl. An important contribution to the infant's lead load is provided by maternal transfer during pregnancy. Our aim was to determine BLL in a large cohort of pregnant women in the UK and to identify the factors that contribute to BLL in pregnant women. Pregnant women resident in the Avon area of the UK were enrolled in the Avon Longitudinal Study of Parents and Children (ALSPAC) in 1991-1992. Whole blood samples were collected at median gestational age of 11 weeks and analysed by inductively coupled plasma dynamic reaction cell mass spectrometry (n = 4285). Self-completion postal questionnaires were used to collect data during pregnancy on lifestyle, diet and other environmental exposures. Statistical analysis was carried out with SPSS v19. The mean±SD BLL was 3.67±1.47 (median 3.41, range 0.41-19.14) µg/dl. Higher educational qualification was found to be one of the strongest independent predictor of BLL in an adjusted backwards stepwise logistic regression to predict maternal BLL caffeine, although further investigation of the effect of calcium on lead levels is needed.

  11. Kinetic study on recovery of metal values in anode slime from used lead batteries

    Energy Technology Data Exchange (ETDEWEB)

    Itoh, S.; Nagasaka, T. [Tohoku Univ., Sendai (Japan). Dept. of Environmental Studies; Ono, J.; Hino, M. [Tohoku Univ., Sendai (Japan). Dept. of Metallurgy

    2004-07-01

    Oxidation experiments were conducted with pure antimony and antimony-lead bismuth alloys to examine the oxidation kinetics and mechanisms used to treat the anode slime produced during lead electrorefining and recovery of antimony from used lead batteries. In order to recycle and recover valuable metals from the used lead batteries, the oxidation experiments were conducted with pure liquid antimony at temperatures between 973 and 1373 K. The study showed that the gas phase mass transfer step is the basic mechanisms that controls the oxidation rate for pure antimony. It was noted that the oxidation rate of the alloy was identical to that of the pure antimony, suggesting that an oxidation reaction of the anode slime proceeds at the same rate as pure antimony. This is one of the advantages of treating anode slime through oxidation. Mass transfer in the gas phase was the rate-determining step in the alloy oxidation reaction. It was concluded that a higher oxygen partial pressure and sufficient gas flow rate at temperature of 1073 K is needed to conserve energy and recovery antimony oxide. 13 refs., 2 tabs., 12 figs.

  12. What can science and technology studies learn from art and design? Reflections on ‘Synthetic Aesthetics’

    Science.gov (United States)

    Calvert, Jane; Schyfter, Pablo

    2016-01-01

    In this paper we reflect on a project called ‘Synthetic Aesthetics’, which brought together synthetic biologists with artists and designers in paired exchanges. We – the STS researchers on the project – were quickly struck by the similarities between our objectives and those of the artists and designers. We shared interests in forging new collaborations with synthetic biologists, ‘opening up’ the science by exploring implicit assumptions, and interrogating dominant research agendas. But there were also differences between us, the most important being that the artists and designers made tangible artefacts, which had an immediacy and an ability to travel, and which seemed to allow different types of discussions from those initiated by our academic texts. The artists and designers also appeared to have the freedom to be more playful, challenging and perhaps subversive in their interactions with synthetic biology. In this paper we reflect on what we learned from working with the artists and designers on the project, and we argue that engaging more closely with art and design can enrich STS work by enabling an emergent form of critique. PMID:28025902

  13. Enhancement of synthetic jets by means of an integrated valve-less pump, Part II: Numerical and experimental studies

    Czech Academy of Sciences Publication Activity Database

    Trávníček, Zdeněk; Tesař, Václav; Wang, A.

    2005-01-01

    Roč. 125, č. 1 (2005), s. 50-58 ISSN 0924-4247 R&D Projects: GA AV ČR(CZ) KSK2076106 Institutional research plan: CEZ:AV0Z20760514 Keywords : periodic jets * synthetic jets Subject RIV: BK - Fluid Dynamics Impact factor: 1.363, year: 2005

  14. 2,6-Lutidine-isatinecate, a semi-synthetic pyrrolizidine alkaloid: X-ray and N. M. R. studies

    Energy Technology Data Exchange (ETDEWEB)

    Drewes, S.E.; Field, J.S.; Pitchford, A.T.; Van Rooyen, P.H.; Dillen, J.L.M.

    1985-09-01

    A semi-synthetic pyrrolizidine alkaloid has been prepared from a necic acid and a pyridine base moiety. N.M.R. and X-ray analyses of this compound were carried out in order to establish the relationship between the structure and chemical shift.

  15. Effects of Synthetic Speech Output on Requesting and Natural Speech Production in Children with Autism: A Preliminary Study

    Science.gov (United States)

    Schlosser, Ralf W.; Sigafoos, Jeff; Luiselli, James K.; Angermeier, Katie; Harasymowyz, Ulana; Schooley, Katherine; Belfiore, Phil J.

    2007-01-01

    Requesting is often taught as an initial target during augmentative and alternative communication intervention in children with autism. Speech-generating devices are purported to have advantages over non-electronic systems due to their synthetic speech output. On the other hand, it has been argued that speech output, being in the auditory…

  16. Low-level lead exposure and mortality in US adults: a population-based cohort study

    Directory of Open Access Journals (Sweden)

    Bruce P Lanphear, ProfMD

    2018-04-01

    Full Text Available Summary: Background: Lead exposure is a risk factor for cardiovascular disease mortality, but the number of deaths in the USA attributable to lead exposure is poorly defined. We aimed to quantify the relative contribution of environmental lead exposure to all-cause mortality, cardiovascular disease mortality, and ischaemic heart disease mortality. Methods: Our study population comprised a nationally representative sample of adults aged 20 years or older who were enrolled in the Third National Health and Nutrition Examination Survey (NHANES-III between 1988 and 1994 and followed up to Dec 31, 2011. Participants had completed a medical examination and home interview and had results for concentrations of lead in blood, cadmium in urine, and other relevant covariates. Individuals were linked with the National Death Index. This study presents extended follow-up of an earlier analysis. Findings: We included 14 289 adults in our study. The geometric mean concentration of lead in blood was 2·71 μg/dL (geometric SE 1·31. 3632 (20% participants had a concentration of lead in blood of at least 5 μg/dL (≥0·24 μmol/L. During median follow-up of 19·3 years (IQR 17·6–21·0, 4422 people died, 1801 (38% from cardiovascular disease and 988 (22% from ischaemic heart disease. An increase in the concentration of lead in blood from 1·0 μg/dL to 6·7 μg/dL (0·048 μmol/L to 0·324 μmol/L, which represents the tenth to 90th percentiles, was associated with all-cause mortality (hazard ratio 1·37, 95% CI 1·17–1·60, cardiovascular disease mortality (1·70, 1·30–2·22, and ischaemic heart disease mortality (2·08, 1·52–2·85. The population attributable fraction of the concentration of lead in blood for all-cause mortality was 18·0% (95% CI 10·9–26·1, which is equivalent to 412 000 deaths annually. Respective fractions were 28·7% (15·5–39·5 for cardiovascular disease mortality and 37·4% (23·4–48·6 for ischaemic heart disease

  17. Structural studies of nanoparticles doped with rare-earth ions in oxyfluoride lead-silicate glasses

    Science.gov (United States)

    Kichanov, Sergey E.; Kozlenko, D. P.; Gorshkova, Yu. E.; Rachkovskaya, G. E.; Zakharevich, G. B.; Savenko, B. N.

    2018-03-01

    Formation of PbF2 nanoparticles as up-conversion luminescent centers in oxyfluoride lead-silicate glass matrixes doped with rare-earth oxides has been studied by means of small-angle neutron scattering and neutron diffraction methods. During a two-stage heat treatment process, amorphous nanoparticles with sizes of 5-7 nm were initially formed, then were aggregated into more complex clusters with average dimensions up to 30 nm. The thermal treating at higher temperature led to crystallization of amorphous nanoparticles and, as a result, the formation of up-conversion luminescent centers in studied lead-silicate glasses. The sizes of amorphous and crystalline nanoparticles, fractional dimensions of density fluctuations in glass materials, as well as the lattice parameters of a phase of PbF2 were calculated.

  18. Surface modification and multiple exciton generation studies of lead(II) sulfide nanoparticles

    Science.gov (United States)

    Zemke, Jennifer M.

    2011-12-01

    Solar energy is a green alternative to fossil fuels but solar technologies to date have been plagued by low conversion efficiencies and high input costs making solar power inaccessible to much of the developing world. Semiconductor nanoparticles (NPs) may provide a route to efficient, economical solar devices through a phenomenon called multiple exciton generation (MEG). Through MEG, semiconductor NPs use a high-energy input photon to create more than one exciton (electron-hole pair) per photon absorbed, thereby exhibiting large photoconversion efficiencies. While MEG has been studied in many NP systems, and we understand some of the factors that affect MEG, a rigorous analysis of the NP-ligand interface with respect to MEG is missing. This dissertation describes how the NP ligand shell directly affects MEG and subsequent charge carrier recombination. Chapter I describes the motivation for studying MEG with respect to NP surface chemistry. Chapter II provides an in-depth overview of the transient absorption experiment used to measure MEG in the NP samples. Chapter III highlights the effect of oleic acid and sodium 2, 3-dimercaptopropane sulfonate on MEG in PbS NPs. The differences in carrier recombination were accounted for by two differences between these ligands: the coordinating atom and/or the secondary structure of the ligand. Because of these hypotheses, experiments were designed to elucidate the origin of these effects by controlling the NP ligand shell. Chapter IV details a viable synthetic route to thiol and amine-capped PbS NPs using sodium 3-mercaptopropane sulfonate as an intermediate ligand. With the versatile ligand exchange described in Chapter IV, the MEG yield and carrier recombination was investigated for ligands with varying headgroups but the same secondary structure. The correlation of ligand donor atom to MEG is outlined in Chapter V. Finally, Chapter VI discusses the conclusions and future outlook of the research reported in this dissertation

  19. A Study of the Central Auditory Function in Stutters by Masking Level Difference and Synthetic Sentence Identification Tests

    Directory of Open Access Journals (Sweden)

    Afsaneh Rajab

    2007-06-01

    Full Text Available Background and Aim: There are evidences that indicate a relationship between auditory processing disor¬ders and stuttering,¬ and any disorder in the central auditory function can be at least one of the underly¬ing causes of stuttering. Even though, using the most state of the art radiographic technologies, i.e. MRI, no definitive answer has been given in relative to this question. In this research, using Mask-ing Level Difference (MLD and Synthetic Sentence Identification (SSI tests, the central auditory func¬tion of stutters and normal group was evaluated.Materials and Methods: In this study was analytic cross-sectional, fifteen male patients with stutter-ing and 15 male normal cases with the age range from 16 to 40 years (average age 26.78 year were evalu¬ated. SSI-ICM, SSI-CCM and MLD tests were performed. The results were compared in both groups.Results: Although stutterers mean MLD was less than that of normal group, the different was not signifi¬cant between stutters and normal group in SSI test in right ear at negative MCRs. There was a signifi¬cant difference in ICM state, but in CCM state, there was no significant difference between the aver¬age score of two groups in various MCRs.Conclusion: The findings of this research is compatible with those of similar researches about the SSI test and the pattern of results, probably indicates a partial dysfunction of brainstem in some of the stutters.

  20. Improvement of Atrophic Acne Scars in Skin of Color Using Topical Synthetic Epidermal Growth Factor (EGF) Serum: A Pilot Study.

    Science.gov (United States)

    Stoddard, Marie Alexia; Herrmann, Jennifer; Moy, Lauren; Moy, Ronald

    2017-04-01

    BACKGROUND: Atrophic scarring in skin of color is a common, permanent, and distressing result of uncontrolled acne vulgaris. Ablative lasers and chemical peels are frequently used to improve the appearance of atrophic scars, primarily through the stimulation of collagen and elastin; however, these treatment modalities are associated with risks, such as dyspigmentation and hypertrophic scarring, especially in patients with darker skin. OBJECTIVE: We evaluated the efficacy of topically applied synthetic epidermal growth factor (EGF) serum in reducing the appearance of atrophic acne scars in skin of color. METHODS: A single-center clinical trial was performed on twelve healthy men and women (average age 32.5) with Fitzpatrick Type IV-V skin and evidence of facial grade II-IV atrophic acne scars. Subjects applied topical EGF serum to the full-face twice daily for 12 weeks. Scar improvement was investigated at each visit using an Investigator Global Assessment (IGA), a Goodman grade, clinical photography, and patient self-assessment. RESULTS: Eleven subjects completed the trial. Compared to baseline, there was an improvement in mean IGA score from 3.36 (SEM = 0.15) to 2.18 (SEM = 0.33). Mean Goodman grade was reduced from 2.73 (SEM = 0.19) to 2.55 (SEM = 0.21). Of the eleven pairs of before and after photographs, nine were correctly chosen as the post-treatment image by a blind investigator. On self-assessment, 81% reported a "good" to "excellent" improvement in their scars compared to baseline (P = 0.004). CONCLUSION: Topical EGF may improve the appearance of atrophic acne scars in skin of color. Additional, larger studies should be conducted to better characterize improvement. J Drugs Dermatol. 2017;16(4):322-326..

  1. [SYNTHETIC PEPTIDE VACCINES].

    Science.gov (United States)

    Sergeyev, O V; Barinsky, I F

    2016-01-01

    An update on the development and trials of synthetic peptide vaccines is reviewed. The review considers the successful examples of specific protection as a result of immunization with synthetic peptides using various protocols. The importance of conformation for the immunogenicity of the peptide is pointed out. An alternative strategy of the protection of the organism against the infection using synthetic peptides is suggested.

  2. Synthetic tsunami waveform catalogs with kinematic constraints

    Directory of Open Access Journals (Sweden)

    M. A. Baptista

    2017-07-01

    Full Text Available In this study we present a comprehensive methodology to produce a synthetic tsunami waveform catalogue in the northeast Atlantic, east of the Azores islands. The method uses a synthetic earthquake catalogue compatible with plate kinematic constraints of the area. We use it to assess the tsunami hazard from the transcurrent boundary located between Iberia and the Azores, whose western part is known as the Gloria Fault. This study focuses only on earthquake-generated tsunamis. Moreover, we assume that the time and space distribution of the seismic events is known. To do this, we compute a synthetic earthquake catalogue including all fault parameters needed to characterize the seafloor deformation covering the time span of 20 000 years, which we consider long enough to ensure the representability of earthquake generation on this segment of the plate boundary. The computed time and space rupture distributions are made compatible with global kinematic plate models. We use the tsunami empirical Green's functions to efficiently compute the synthetic tsunami waveforms for the dataset of coastal locations, thus providing the basis for tsunami impact characterization. We present the results in the form of offshore wave heights for all coastal points in the dataset. Our results focus on the northeast Atlantic basin, showing that earthquake-induced tsunamis in the transcurrent segment of the Azores–Gibraltar plate boundary pose a minor threat to coastal areas north of Portugal and beyond the Strait of Gibraltar. However, in Morocco, the Azores, and the Madeira islands, we can expect wave heights between 0.6 and 0.8 m, leading to precautionary evacuation of coastal areas. The advantages of the method are its easy application to other regions and the low computation effort needed.

  3. Synthetic tsunami waveform catalogs with kinematic constraints

    Science.gov (United States)

    Baptista, Maria Ana; Miranda, Jorge Miguel; Matias, Luis; Omira, Rachid

    2017-07-01

    In this study we present a comprehensive methodology to produce a synthetic tsunami waveform catalogue in the northeast Atlantic, east of the Azores islands. The method uses a synthetic earthquake catalogue compatible with plate kinematic constraints of the area. We use it to assess the tsunami hazard from the transcurrent boundary located between Iberia and the Azores, whose western part is known as the Gloria Fault. This study focuses only on earthquake-generated tsunamis. Moreover, we assume that the time and space distribution of the seismic events is known. To do this, we compute a synthetic earthquake catalogue including all fault parameters needed to characterize the seafloor deformation covering the time span of 20 000 years, which we consider long enough to ensure the representability of earthquake generation on this segment of the plate boundary. The computed time and space rupture distributions are made compatible with global kinematic plate models. We use the tsunami empirical Green's functions to efficiently compute the synthetic tsunami waveforms for the dataset of coastal locations, thus providing the basis for tsunami impact characterization. We present the results in the form of offshore wave heights for all coastal points in the dataset. Our results focus on the northeast Atlantic basin, showing that earthquake-induced tsunamis in the transcurrent segment of the Azores-Gibraltar plate boundary pose a minor threat to coastal areas north of Portugal and beyond the Strait of Gibraltar. However, in Morocco, the Azores, and the Madeira islands, we can expect wave heights between 0.6 and 0.8 m, leading to precautionary evacuation of coastal areas. The advantages of the method are its easy application to other regions and the low computation effort needed.

  4. Coupled study of radionuclides and stable lead isotopes in Western Mediterranean

    International Nuclear Information System (INIS)

    Miralles, J.

    2004-05-01

    The aim of this work is to identified an environmental deposit able to have stored the atmospheric signal over large time-scale leaning our investigations on lead stable isotopes ( 206 Pb, 207 Pb, 208 Pb) and radionuclide ( 210 Pb, 137 Cs, 239 Pu, 240 Pu) analysis. Owing to prior studies on anthropogenic lead sources, emission intensity and sedimentary accumulation, we choose to investigate the marine sediments of the Western Mediterranean. In the Gulf of Lions, the sedimentary accumulation is 110 ± 7 μg.cm -2 high in good agreement with the atmospheric inventory estimate we made from salt marshes of Camargue (99 μg.cm -2 ). The reconstructed lead accumulation through a modelling step coupling 210 Pb and stable isotopes corroborates the regional anthropogenic emissions (Ferrand, 1996). Briefly, in this context of the marine sediments are a relevant proxy to study past lead atmospheric concentration over the last hundred years. In the Alboran Sea, the study area is less constrained and more complex in terms of climatic, meteorological and hydrological conditions. The sedimentary inventory is of 153 ± 47 μg.cm -2 , 1,5 higher than in the margin sediments of the Gulf of Lions. The analysis of aerosols, sediments and settling particles evidences a continuity between the atmospheric signal and the sedimentary record. In spite of this encouraging results, the knowledge of the Alboran system is still too restricted in order to unambiguously conclude on accuracy of deep marine sediments of this area to study past atmospheric fallouts. (author)

  5. Lead Exposure Assessment among Pregnant Women, Newborns, and Children: Case Study from Karachi, Pakistan.

    Science.gov (United States)

    Fatmi, Zafar; Sahito, Ambreen; Ikegami, Akihiko; Mizuno, Atsuko; Cui, Xiaoyi; Mise, Nathan; Takagi, Mai; Kobayashi, Yayoi; Kayama, Fujio

    2017-04-13

    Lead (Pb) in petrol has been banned in developed countries. Despite the control of Pb in petrol since 2001, high levels were reported in the blood of pregnant women and children in Pakistan. However, the identification of sources of Pb has been elusive due to its pervasiveness. In this study, we assessed the lead intake of pregnant women and one- to three-year-old children from food, water, house dust, respirable dust, and soil. In addition, we completed the fingerprinting of the Pb isotopic ratios (LIR) of petrol and secondary sources (food, house-dust, respirable dust, soil, surma (eye cosmetics)) of exposure within the blood of pregnant women, newborns, and children. Eight families, with high (~50 μg/dL), medium (~20 μg/dL), and low blood levels (~10 μg/dL), were selected from 60 families. The main sources of exposure to lead for children were food and house-dust, and those for pregnant women were soil, respirable dust, and food. LIR was determined by inductively coupled plasma quadrupole mass spectrometry (ICP-QMS) with a two sigma uncertainty of ±0.03%. The LIR of mothers and newborns was similar. In contrast, surma , and to a larger extent petrol, exhibited a negligible contribution to both the child's and mother's blood Pb. Household wet-mopping could be effective in reducing Pb exposure. This intake assessment could be replicated for other developing countries to identify sources of lead and the burden of lead exposure in the population.

  6. Blood Lead Levels and Delayed Onset of Puberty in a Longitudinal Study of Russian Boys

    Science.gov (United States)

    Williams, Paige L.; Sergeyev, Oleg; Lee, Mary M.; Korrick, Susan A.; Burns, Jane S.; Humblet, Olivier; DelPrato, Julie; Revich, Boris; Hauser, Russ

    2011-01-01

    Background World-wide trends towards earlier pubertal onset have raised concerns regarding the potential role of environmental exposures, including lead. Previous animal studies and studies in girls have revealed associations of lead with perturbations in pubertal onset. We evaluated the association of blood lead levels (BLLs) with pubertal onset in a longitudinal cohort of Russian boys. Methods 489 Russian boys were enrolled in 2003–2005 at ages 8–9 years and followed annually through May 2008. Cox proportional hazards models were used to evaluate the association of BLLs at enrollment with time to pubertal onset during follow-up based on testicular volume (TV) and pubertal staging, adjusting for birth characteristics, nutritional status, maternal exposures during pregnancy, height and BMI, and socioeconomic status. Results 481 boys had BLLs, with median=3 µg/dL and 28% ≥ 5 µg/dL. The percentage of pubertal boys increased with age, from 12% at age 8 to 83% at age 12 as defined by TV>3ml, from 22% to 90% as defined by genitalia stage 2 or higher, and from 4% to 40% as defined by pubic hair stage 2 or higher. After adjustment for potential confounders including BMI and height, boys with high BLLs (≥ 5 µg/dL) had a 24%–31% reduced risk of pubertal onset based on TV>3ml (Hazard Ratio (HR)= 0.73; 95% CI: 0.55, 0.97, p=0.03), genital staging (HR=0.76, 95% CI: 0.59, 0.98, p=0.04), and pubic hair staging (HR=0.69, 95% CI: 0.44, 1.07, p=0.10) as compared to those with lower lead levels. Pubertal onset occurred 6–8 months later on average for boys with high BLLs compared to those with BLLs < 5 µg/dL. Conclusions Higher blood lead was associated with later pubertal onset in this prospective study of peri-pubertal Russian boys. Given the large numbers of children with BLLs≥5 µg/dL worldwide, this shift has important public health implications and supports review of current lead policies. PMID:20368318

  7. Apparent Consumption vs. Total Consumption--A Lead-Acid Battery Case Study

    Science.gov (United States)

    Wilburn, David R.; Buckingham, David A.

    2006-01-01

    Introduction: This report compares estimates of U.S. apparent consumption of lead with estimates of total U.S. consumption of this mineral commodity from a materials flow perspective. The difference, attributed to the amount of lead contained in imported and exported products, was found to be significant for this sector. The study also assesses the effects of including mineral commodities incorporated in manufactured products on the interpretation of observed trends in minerals consumption and trade. Materials flow is a systems approach to understanding what happens to the materials we use from the time a material is extracted, through its processing and manufacturing, to its ultimate disposition. The U.S. Geological Survey (USGS) provides accurate and detailed mineral production and mineral commodity consumption statistics that are essential for government, nongovernment organizations, and the public to gain a better understanding of how and where materials are used and their effect on the environment and society. Published statistics on mineral apparent consumption are limited to estimates of consumption of raw material forms (ore, concentrate, and [or] refined metal). For this study, apparent consumption is defined as mine production + secondary refined production + imports (concentrates and refined metal) ? exports (concentrates and refined metal) + adjustments for government and industry stock changes. These estimates do not account for the amount of mineral commodities contained in manufactured products that are imported to the United States, nor do they deduct the amount of these mineral commodities contained in manufactured products that are exported from the United States. When imports or exports of manufactured products contribute significantly to the total use of a particular raw material, an estimate of consumption that does not consider the incorporated forms of these mineral commodities within imported or exported manufactured products can be either

  8. Wettability study of lead free solder paste and its effect towards multiple reflow

    Directory of Open Access Journals (Sweden)

    Idris Siti Rabiatull Aisha

    2016-01-01

    Full Text Available Nowadays, wafer bumping using solder paste has come into focus as it provides a low cost method. However, since the industries are moving towards lead-free electronic packaging, a new type of no-clean flux was produced specifically for lead-free solder paste. Therefore, this study is used to evaluate the wettability of two different types of no-clean flux onto copper substrate. Besides, its effect towards multiple reflow was also studied. Reflow soldering was conducted for both types of solder paste that contained different type of no-clean flux for up to double reflow. Two different reflow profile was used. The results showed that the Flux A exhibit better soldering performance after first and second reflow soldering. In addition, type of intermetallic compound (IMC found after first reflow remain the same even after second reflow which was Cu-Sn based. This is shows that Flux A manage to control the diffusion process which will finally leads to a better solder joint performance. Nevertheless, mechanical testing should be carried out in order to evaluate the solder joint strength.

  9. Experimental studies of dynamic impact response with scale models of lead shielded radioactive material shipping containers

    International Nuclear Information System (INIS)

    Robinson, R.A.; Hadden, J.A.; Basham, S.J.

    1978-01-01

    Preliminary experimental studies of dynamic impact response of scale models of lead-shielded radioactive material shipping containers are presented. The objective of these studies is to provide DOE/ECT with a data base to allow the prediction of a rational margin of confidence in overviewing and assessing the adequacy of the safety and environmental control provided by these shipping containers. Replica scale modeling techniques were employed to predict full scale response with 1/8, 1/4, and 1/2 scale models of shipping containers that are used in the shipment of spent nuclear fuel and high level wastes. Free fall impact experiments are described for scale models of plain cylindrical stainless steel shells, stainless steel shells filled with lead, and replica scale models of radioactive material shipping containers. Dynamic induced strain and acceleration measurements were obtained at several critical locations on the models. The models were dropped from various heights, attitudes to the impact surface, with and without impact limiters and at uniform temperatures between -40 and 175 0 C. In addition, thermal expansion and thermal gradient induced strains were measured at -40 and 175 0 C. The frequency content of the strain signals and the effect of different drop pad compositions and stiffness were examined. Appropriate scale modeling laws were developed and scaling techniques were substantiated for predicting full scale response by comparison of dynamic strain data for 1/8, 1/4, and 1/2 scale models with stainless steel shells and lead shielding

  10. X-ray studies of krypton, xenon and lead inclusions in aluminium single crystals

    International Nuclear Information System (INIS)

    Grabaek, L.; Bohr, J.; Johnson, E.; Andersen, H.H.; Johansen, A.; Sarholt-Kristensen, L.

    1988-01-01

    Samples of aluminum single crystals with [111] normal were implanted with either Kr, Xe or Pb. The small inclusions formed due to the immiscibility of these elements and aluminum were then studied by X-ray diffraction at various temperatures. The analysis showed that the small noble gas inclusions (≅ 23 A) formed after implantation are solid up to at least 541 Kelvin. During the first heating cycle the inclusions grow and in a second heating cycle it is found that the largest of the inclusions (≅ 42 A) melt below 260 Kelvin. The lead inclusions grow during the first and the second temperature cycle. Gradual melting was observed in a temperature interval from 621-660 Kelvin, which is above 603 Kelvin, the melting temperature of bulk lead. (orig.)

  11. A Comparative Study of Lithium Ion to Lead Acid Batteries for use in UPS Applications

    DEFF Research Database (Denmark)

    Stan, Ana-Irina; Swierczynski, Maciej Jozef; Stroe, Daniel Ioan

    2014-01-01

    batteries, which are currently used in UPS applications. The main purpose of this paper is to analyze how Li-ion batteries can become a useful alternative to present VRLA. In this study, three different electrochemical battery technologies were investigated; two of the most appealing Li-ion chemistries...... ion batteries are getting more and more attention for their use in the back-up power systems and UPSs, because of their superior characteristics, which include increased safety and higher gravimetric and volumetric energy densities. This fact allows them to be smaller in size and weight less than VRLA......Uninterruptible power supply (UPS) systems have incorporated in their structure an electrochemical battery which allows for smooth power supply when a power failure occurs. In general, UPS systems are based on lead acid batteries; mainly a valve regulated lead acid (VRLA) battery. Recently, lithium...

  12. LEADING WITH LEADING INDICATORS

    International Nuclear Information System (INIS)

    PREVETTE, S.S.

    2005-01-01

    This paper documents Fluor Hanford's use of Leading Indicators, management leadership, and statistical methodology in order to improve safe performance of work. By applying these methods, Fluor Hanford achieved a significant reduction in injury rates in 2003 and 2004, and the improvement continues today. The integration of data, leadership, and teamwork pays off with improved safety performance and credibility with the customer. The use of Statistical Process Control, Pareto Charts, and Systems Thinking and their effect on management decisions and employee involvement are discussed. Included are practical examples of choosing leading indicators. A statistically based color coded dashboard presentation system methodology is provided. These tools, management theories and methods, coupled with involved leadership and employee efforts, directly led to significant improvements in worker safety and health, and environmental protection and restoration at one of the nation's largest nuclear cleanup sites

  13. Public sector accounting in the education syllabi of leading chartered accountant professional bodies: A comparative study

    Directory of Open Access Journals (Sweden)

    Ahmed Mohammadali-Haji

    2016-05-01

    Full Text Available Public sector accounting has emerged as an area of concern within the sphere of professional accounting education. The International Federation of Accountants (IFAC allows its member bodies to apply discretion in the application of public sector accounting education requirements. This study explored the nature and extent to which public sector accounting features in the education syllabi of the leading chartered accountant professional bodies that form part of the IFAC contingent. By following an explorative approach, the study identified international trends within the ambit of public sector accounting education and provides guidance for other professional bodies in assessing the nature and extent of their public sector accounting education requirements

  14. Space Synthetic Biology Project

    Science.gov (United States)

    Howard, David; Roman, Monsi; Mansell, James (Matt)

    2015-01-01

    Synthetic biology is an effort to make genetic engineering more useful by standardizing sections of genetic code. By standardizing genetic components, biological engineering will become much more similar to traditional fields of engineering, in which well-defined components and subsystems are readily available in markets. Specifications of the behavior of those components and subsystems can be used to model a system which incorporates them. Then, the behavior of the novel system can be simulated and optimized. Finally, the components and subsystems can be purchased and assembled to create the optimized system, which most often will exhibit behavior similar to that indicated by the model. The Space Synthetic Biology project began in 2012 as a multi-Center effort. The purpose of this project was to harness Synthetic Biology principals to enable NASA's missions. A central target for application was to Environmental Control & Life Support (ECLS). Engineers from NASA Marshall Space Flight Center's (MSFC's) ECLS Systems Development Branch (ES62) were brought into the project to contribute expertise in operational ECLS systems. Project lead scientists chose to pursue the development of bioelectrochemical technologies to spacecraft life support. Therefore, the ECLS element of the project became essentially an effort to develop a bioelectrochemical ECLS subsystem. Bioelectrochemical systems exploit the ability of many microorganisms to drive their metabolisms by direct or indirect utilization of electrical potential gradients. Whereas many microorganisms are capable of deriving the energy required for the processes of interest (such as carbon dioxide (CO2) fixation) from sunlight, it is believed that subsystems utilizing electrotrophs will exhibit smaller mass, volume, and power requirements than those that derive their energy from sunlight. In the first 2 years of the project, MSFC personnel conducted modeling, simulation, and conceptual design efforts to assist the

  15. Advanced airbreathing engine lubricants study with a tetraester fluid and a synthetic paraffinic oil at 492 K (425 F)

    Science.gov (United States)

    Zaretsky, E. V.; Bamberger, E. N.

    1972-01-01

    Groups of 120-mm-bore angular-contact ball bearings made from AISI M-50 steel were fatigue tested with a tetraester and a synthetic paraffinic oil at a bearing temperature of 492 K (425 F) in an air environment. Bearing life exceeded AFBMA-predicted (catalog) life by factors in excess of 4 and 10 for the tetraester and synthetic paraffinic fluids, respectively. The final viscosities after 500 hours of operation were 14 and 6 times the initial values, respectively. During the same time period, when the test oil is replaced at a rate approximating the replenishment rate in actual commerical engine usage, no significant increase in lubricant viscosity with time was observed.

  16. VO2+ ions in zinc lead borate glasses studied by EPR and optical absorption techniques.

    Science.gov (United States)

    Prakash, P Giri; Rao, J Lakshmana

    2005-09-01

    Electron paramagnetic resonance (EPR) and optical absorption spectra of vanadyl ions in zinc lead borate (ZnO-PbO-B2O3) glass system have been studied. EPR spectra of all the glass samples exhibit resonance signals characteristic of VO2+ ions. The values of spin-Hamiltonian parameters indicate that the VO2+ ions in zinc lead borate glasses were present in octahedral sites with tetragonal compression and belong to C4V symmetry. The spin-Hamiltonian parameters g and A are found to be independent of V2O5 content and temperature but changing with ZnO content. The decrease in Deltag( parallel)/Deltag( perpendicular) value with increase in ZnO content indicates that the symmetry around VO2+ ions is more octahedral. The decrease in intensity of EPR signal above 10 mol% of V2O5 is attributed to a fall in the ratio of the number of V4+ ions (N4) to the number of V5+ ions (N5). The number of spins (N) participating in resonance was calculated as a function of temperature for VO2+ doped zinc lead borate glass sample and the activation energy was calculated. From the EPR data, the paramagnetic susceptibility was calculated at various temperatures and the Curie constant was evaluated from the 1/chi-T graph. The optical absorption spectra show single absorption band due to VO2+ ions in tetragonally distorted octahedral sites.

  17. Kinetic and equilibrium studies in removing lead ions from aqueous solutions by natural sepiolite

    Energy Technology Data Exchange (ETDEWEB)

    Bektas, Nihal; Agim, Burcu Akman; Kara, Serdar

    2004-08-09

    The capacity of sepiolite for the removal of lead ions from aqueous solution was investigated under different experimental conditions. The Langmuir and Freundlich equations, which are in common use for describing sorption equilibrium for wastewater-treatment applications, were applied to data. The constants and correlation coefficients of these isotherm models for the present system at different conditions such as pH, temperature and particle size were calculated and compared. The equilibrium process was well described by the Langmuir isotherm model and the maximum sorption capacity was found to be 93.4 mg/g for the optimal experimental condition. The thermodynamic parameters ({delta}G deg., {delta}H deg. and {delta}S deg.) for lead sorption on the sepiolite were also determined from the temperature dependence. The influences of specific parameters such as the agitation speed, particle size and initial concentration for the kinetic studies were also examined. The sorption kinetics were tested for first order reversible, pseudo-first order and pseudo-second order reaction and the rate constants of kinetic models were calculated. The best correlation coefficients were obtained using the pseudo-second order kinetic model, indicating that lead uptake process followed the pseudo-second order rate expression.

  18. A cohort mortality study of lead-exposed workers in the USA, Finland and the UK.

    Science.gov (United States)

    Steenland, Kyle; Barry, Vaughn; Anttila, Ahti; Sallmén, Markku; McElvenny, Damien; Todd, A C; Straif, Kurt

    2017-11-01

    To investigate further whether inorganic lead is a carcinogen among adults, or associated with increased blood pressure and kidney damage, via a large mortality study. We conducted internal analyses via Cox regression of mortality in three cohorts of lead-exposed workers with blood lead (BL) data (USA, Finland, UK), including over 88 000 workers and over 14 000 deaths. Our exposure metric was maximum BL. We also conducted external analyses using country-specific background rates. The combined cohort had a median BL of 26 µg/dL, a mean first-year BL test of 1990 and was 96% male. Fifty per cent had more than one BL test (mean 7). Significant (p40 µg/dL; for bladder, lung and larynx cancer; and for COPD. In a small subsample of the US cohort (n=115) who were interviewed, we found no association between smoking and BL. We found strong positive mortality trends, with increasing BL level, for several outcomes in internal analysis. Many of these outcomes are associated with smoking, for which we had no data. A borderline trend was found for brain cancer, not associated with smoking. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  19. Sky View Factors from Synthetic Fisheye Photos for Thermal Comfort Routing—A Case Study in Phoenix, Arizona

    Directory of Open Access Journals (Sweden)

    Ariane Middel

    2017-03-01

    Full Text Available The Sky View Factor (SVF is a dimension-reduced representation of urban form and one of the major variables in radiation models that estimate outdoor thermal comfort. Common ways of retrieving SVFs in urban environments include capturing fisheye photographs or creating a digital 3D city or elevation model of the environment. Such techniques have previously been limited due to a lack of imagery or lack of full scale detailed models of urban areas. We developed a web based tool that automatically generates synthetic hemispherical fisheye views from Google Earth at arbitrary spatial resolution and calculates the corresponding SVFs through equiangular projection. SVF results were validated using Google Maps Street View and compared to results from other SVF calculation tools. We generated 5-meter resolution SVF maps for two neighborhoods in Phoenix, Arizona to illustrate fine-scale variations of intra-urban horizon limitations due to urban form and vegetation. To demonstrate the utility of our synthetic fisheye approach for heat stress applications, we automated a radiation model to generate outdoor thermal comfort maps for Arizona State University’s Tempe campus for a hot summer day using synthetic fisheye photos and on-site meteorological data. Model output was tested against mobile transect measurements of the six-directional radiant flux density. Based on the thermal comfort maps, we implemented a pedestrian routing algorithm that is optimized for distance and thermal comfort preferences. Our synthetic fisheye approach can help planners assess urban design and tree planting strategies to maximize thermal comfort outcomes and can support heat hazard mitigation in urban areas.

  20. Genome-wide association study of blood lead shows multiple associations near ALAD

    OpenAIRE

    Warrington, Nicole M.; Zhu, Gu; Dy, Veronica; Heath, Andrew C.; Madden, Pamela A.F.; Hemani, Gibran; Kemp, John P.; Mcmahon, George; St Pourcain, Beate; Timpson, Nicholas J.; Taylor, Caroline M.; Golding, Jean; Lawlor, Debbie A.; Steer, Colin; Montgomery, Grant W.

    2015-01-01

    Exposure to high levels of environmental lead, or biomarker evidence of high body lead content, is associated with anaemia, developmental and neurological deficits in children, and increased mortality in adults. Adverse effects of lead still occur despite substantial reduction in environmental exposure. There is genetic variation between individuals in blood lead concentration but the polymorphisms contributing to this have not been defined. We measured blood or erythrocyte lead content, and ...

  1. The effects of lead time and visual aids in TTO valuation: a study of the EQ-VT framework

    NARCIS (Netherlands)

    N. Luo (Nan); M. Li (Minghui); E.A. Stolk (Elly); N. Devlin (Nancy)

    2013-01-01

    markdownabstract__Abstract__ __Background__ The effect of lead time in time trade-off (TTO) valuation is not well understood. The purpose of this study was to investigate the effects on health-state valuation of the length of lead time and the way the lead-time TTO task is displayed visually.

  2. Studies of a self-cooled lead lithium blanket for HiPER reactor

    Science.gov (United States)

    Juárez, R.; Sanz, J.; Sánchez, C.; Zanzi, C.; Hernández, J.; Perlado, J. M.

    2013-11-01

    Within the frame of the HiPER reactor, we propose and study a Self Cooled Lead Lithium blanket with two different cooling arrangements of the system First Wall - Blanket for the HiPER reactor: Integrated First Wall Blanket and Separated First Wall Blanket. We compare the two arrangements in terms of power cycle efficiency, operation flexibility in out-off-normal situations and proper cooling and acceptable corrosion. The Separated First Wall Blanket arrangement is superior in all of them, and it is selected as the advantageous proposal for the HiPER reactor blanket. However, it still has to be improved from the standpoint of proper cooling and corrosion rates.

  3. Structural investigations of bismuth lead borosilicate glasses under the influence of gamma irradiation through ultrasonic studies

    Science.gov (United States)

    Bootjomchai, Cherdsak; Laopaiboon, Jintana; Laopaiboon, Raewat

    2012-04-01

    The ultrasonic velocity measurements for different compositions of irradiated bismuth lead borosilicate glasses xBi2O3-(50-x)PbO-20B2O3-30SiO2 (x=2, 4, 6, 8, and 10 mol.%) were performed at room temperature using pulse-echo technique. Densities of glass samples were measured by Archimedes' principle using n-hexane as the immersion liquid. The results from the studies show that ultrasonic velocity, elastic moduli, Poisson's ratio, microhardness, and the Debye temperature increase with increasing bismuth oxide content and increasing gamma-radiation dose (3-12 Gy).

  4. Compressible Navier-Stokes equations: A study of leading edge effects

    Science.gov (United States)

    Hariharan, S. I.; Karbhari, P. R.

    1987-01-01

    A computational method is developed that allows numerical calculations of the time dependent compressible Navier-Stokes equations.The current results concern a study of flow past a semi-infinite flat plate.Flow develops from given inflow conditions upstream and passes over the flat plate to leave the computational domain without reflecting at the downstream boundary. Leading edge effects are included in this paper. In addition, specification of a heated region which gets convected with the flow is considered. The time history of this convection is obtained, and it exhibits a wave phenomena.

  5. Sintering study in vertical fixed bed reactor for synthetic aggregate production; Estudo da sinterizacao em reator vertical de leito fixo para producao de agregado sintetico

    Energy Technology Data Exchange (ETDEWEB)

    Quaresma, D.S.; Neves, A.S.S.; Melo, A.O.; Pereira, L.F.S.; Bezerra, P.T.S.; Macedo, E.N.; Souza, J.A.S., E-mail: danysq@gmail.com [Universidade Federal do Para (UFPA), Belem, PA (Brazil). Faculdade de Engenharia Quimica

    2017-04-15

    The synthetic aggregates are being employed in civil construction for the reduction of mineral extraction activities. Within this context, the recycling of industrial waste is the basis of the majority of processes to reduce the exploitation of mineral resources. In this work the sintering in a vertical fixed bed reactor for synthetic aggregate production using 20% pellets and 80% charcoal was studied. The pellets were prepared from a mixture containing clay, charcoal and fly ash. Two experiments varying the speed of air sucking were carried out. The material produced was analyzed by X-ray diffraction, scanning electron microscopy, measures of their ceramic properties, and particle size analysis. The results showed that the solid-state reactions, during the sintering process, were efficient and the produced material was classified as coarse lightweight aggregate. The process is interesting for the sintering of aggregates, and can be controlled by composition, particle size, temperature gradient and gaseous flow. (author)

  6. The European power plant conceptual study: Helium-cooled lithium-lead reactor concept

    International Nuclear Information System (INIS)

    Sardain, P.; Maisonnier, D.; Di Pace, L.; Giancarli, L.; Puma, A. Li; Norajitra, P.; Orden, A.; Arenaza, E.; Ward, D.

    2006-01-01

    The power plant conceptual study (PPCS) carried out in Europe between 2001 and 2004, aimed at the demonstration of the credibility, the safety and environmental advantages and the potential economic viability of future fusion power reactors. A set of requirements was issued by industry and utilities concerning safety, operational and economic aspects. In this framework, the helium-cooled lithium-lead (HCLL) reactor concept has been studied, which was based on limited extrapolation in both present physics and technology. The HCLL blanket is considered in Europe as a possible concept for DEMO. The net electric power was set at about 1500 MW e . The maintenance scheme considered is based on the removal of blanket modules through the equatorial ports and the removal of divertor cassettes through the lower ports of the vacuum vessel. This scheme shows the potential for good overall plant availability (75%). The balance of plant has been studied, taking into account the following systems: the primary heat transport system, the lithium lead circulation system and the secondary heat transfer system. A safety analysis has been carried out. A set of envelope accident sequences was identified using a functional failure mode and effects analysis (FFMEA) methodology and the deterministic assessment of the scenarios was carried out using best estimate computer codes. It is concluded that the HCLL reactor concept meets the overall objectives of the PPCS

  7. Part I: A comparative study of bismuth-modified screen-printed electrodes for lead detection

    Energy Technology Data Exchange (ETDEWEB)

    Calvo Quintana, Josefina [Dipartimento di Scienze e Tecnologie Chimiche, Universita di Roma Tor Vergata, Via della Ricerca Scientifica, 00133 Rome (Italy); Consorzio Interuniversitario Biostrutture e Biosistemi ' INBB' , Viale Medaglie d' Oro 305, 00136 Rome (Italy); Arduini, Fabiana, E-mail: fabiana.arduini@uniroma2.it [Dipartimento di Scienze e Tecnologie Chimiche, Universita di Roma Tor Vergata, Via della Ricerca Scientifica, 00133 Rome (Italy); Consorzio Interuniversitario Biostrutture e Biosistemi ' INBB' , Viale Medaglie d' Oro 305, 00136 Rome (Italy); Amine, Aziz [Faculte des Sciences et Techniques, B.P.146, Mohammadia, Morocco, Rome (Italy); Punzo, Francesco; Destri, Giovanni Li [LAMSUN and CSGI at Dipartimento di Scienze Chimiche, Universita degli Studi di Catania, Viale A. Doria 6, 95125, Catania (Italy); Bianchini, Chiara [Dipartimento di Ingegneria Chimica Materiali Ambienti dell' Universita degli Studi ' La Sapienza' di Roma, via Eudossiana 18, 00184 Rome (Italy); Zane, Daniela; Curulli, Antonella [Istituto per lo Studio dei Materiali Nanostrutturati (ISMN)-CNR,via del Castro Laurenziano 7, 00161 Rome (Italy); Palleschi, Giuseppe; Moscone, Danila [Dipartimento di Scienze e Tecnologie Chimiche, Universita di Roma Tor Vergata, Via della Ricerca Scientifica, 00133 Rome (Italy); Consorzio Interuniversitario Biostrutture e Biosistemi ' INBB' , Viale Medaglie d' Oro 305, 00136 Rome (Italy)

    2011-11-30

    Highlights: Black-Right-Pointing-Pointer 'In situ' Bi-SPE has higher sensitivity than 'ex situ' Bi-SPE and 'Bi{sub 2}O{sub 3} bulk' SPE. Black-Right-Pointing-Pointer Electrochemical treatment of SPE before Bi film deposition allows one to reach low LOD. Black-Right-Pointing-Pointer The linearity of Pb{sup 2+} in HCl and HClO{sub 4} is greatly affected by the ionic strength. Black-Right-Pointing-Pointer Satisfactory values of the recovery percentage were obtained in drinking water samples. - Abstract: Lead determination was carried out in the frame of the European Union project Biocop ( (www.biocop.org)) using a bismuth-modified screen-printed electrode (Bi-SPE) and the stripping analysis technique. In order to choose a sensitive Bi-SPE for lead detection, an analytical comparative study of electrodes modified by Bi using 'in situ', 'ex situ' and 'bulk' procedures was carried out. On the basis of the results obtained, we confirmed that the 'in situ' procedure resulted in better analytical performances with respect to not only 'ex situ' but also to 'Bi{sub 2}O{sub 3} bulk' modified electrodes, allowing for a linear range of lead ion concentration from 0.5 to 100 {mu}g L{sup -1} and a detection limit of 0.15 {mu}g L{sup -1}. We demonstrated that, before the Bi film deposition, an oxidative electrochemical pre-treatment of the working electrode could be useful because it eliminates traces of lead in the graphite-ink, as shown with stripping measurements. It also improves the electrochemical performance of the electrodes as demonstrated with Electrochemical Impedance Spectroscopy (EIS) measurements. The influence of different analytical parameters, such as the electrolyte solution composition (acetate buffer, chloridric acid, nitric acid, perchloric acid) and the ionic strength was investigated in order to evaluate how to treat the sample before the analysis. The morphology of

  8. Environmental factors predicting blood lead levels in pregnant women in the UK: the ALSPAC study.

    Directory of Open Access Journals (Sweden)

    Caroline M Taylor

    Full Text Available Lead is a widespread environmental toxin. The behaviour and academic performance of children can be adversely affected even at low blood lead levels (BLL of 5-10 µg/dl. An important contribution to the infant's lead load is provided by maternal transfer during pregnancy.Our aim was to determine BLL in a large cohort of pregnant women in the UK and to identify the factors that contribute to BLL in pregnant women.Pregnant women resident in the Avon area of the UK were enrolled in the Avon Longitudinal Study of Parents and Children (ALSPAC in 1991-1992. Whole blood samples were collected at median gestational age of 11 weeks and analysed by inductively coupled plasma dynamic reaction cell mass spectrometry (n = 4285. Self-completion postal questionnaires were used to collect data during pregnancy on lifestyle, diet and other environmental exposures. Statistical analysis was carried out with SPSS v19.The mean±SD BLL was 3.67±1.47 (median 3.41, range 0.41-19.14 µg/dl. Higher educational qualification was found to be one of the strongest independent predictor of BLL in an adjusted backwards stepwise logistic regression to predict maternal BLL <5 or ≥5 µg/dl (odds ratio 1.26, 95% confidence interval 1.12-1.42; p<0.001. Other predictive factors included cigarette smoking, alcohol and coffee drinking, and heating the home with a coal fire, with some evidence for iron and calcium intake having protective effects.The mean BLL in this group of pregnant women is higher than has been found in similar populations in developed countries. The finding that high education attainment was independently associated with higher BLL was unexpected and currently unexplained. Reduction in maternal lead levels can best be undertaken by reducing intake of the social drugs cigarettes, alcohol and caffeine, although further investigation of the effect of calcium on lead levels is needed.

  9. Part I: A comparative study of bismuth-modified screen-printed electrodes for lead detection

    International Nuclear Information System (INIS)

    Calvo Quintana, Josefina; Arduini, Fabiana; Amine, Aziz; Punzo, Francesco; Destri, Giovanni Li; Bianchini, Chiara; Zane, Daniela; Curulli, Antonella; Palleschi, Giuseppe; Moscone, Danila

    2011-01-01

    Highlights: ► “In situ” Bi-SPE has higher sensitivity than “ex situ” Bi-SPE and “Bi 2 O 3 bulk” SPE. ► Electrochemical treatment of SPE before Bi film deposition allows one to reach low LOD. ► The linearity of Pb 2+ in HCl and HClO 4 is greatly affected by the ionic strength. ► Satisfactory values of the recovery percentage were obtained in drinking water samples. - Abstract: Lead determination was carried out in the frame of the European Union project Biocop ( (www.biocop.org)) using a bismuth-modified screen-printed electrode (Bi-SPE) and the stripping analysis technique. In order to choose a sensitive Bi-SPE for lead detection, an analytical comparative study of electrodes modified by Bi using “in situ”, “ex situ” and “bulk” procedures was carried out. On the basis of the results obtained, we confirmed that the “in situ” procedure resulted in better analytical performances with respect to not only “ex situ” but also to “Bi 2 O 3 bulk” modified electrodes, allowing for a linear range of lead ion concentration from 0.5 to 100 μg L −1 and a detection limit of 0.15 μg L −1 . We demonstrated that, before the Bi film deposition, an oxidative electrochemical pre-treatment of the working electrode could be useful because it eliminates traces of lead in the graphite-ink, as shown with stripping measurements. It also improves the electrochemical performance of the electrodes as demonstrated with Electrochemical Impedance Spectroscopy (EIS) measurements. The influence of different analytical parameters, such as the electrolyte solution composition (acetate buffer, chloridric acid, nitric acid, perchloric acid) and the ionic strength was investigated in order to evaluate how to treat the sample before the analysis. The morphology of prepared “in situ” Bi-SPEs was also characterized by Atomic Force Microscopy (AFM). Finally, the Bi-SPEs were used to determine the concentration of lead ions in tap and commercial water

  10. Lead poisoning in shooting-range workers in Gauteng Province, South Africa: Two case studies

    Directory of Open Access Journals (Sweden)

    S Naidoo

    2017-04-01

    Full Text Available Background. Lead exposure constitutes a major public health concern globally. Relative to developed nations, lead exposure is understudied and poorly addressed in Africa, and there is a dearth of information available to inform lead poisoning prevention strategies, even in high-risk groups such as workers in shooting ranges who are potentially exposed to lead daily. Methods. Two workers at a private shooting range in Gauteng, South Africa (SA, had blood lead levels and exposure histories taken. Results. Workers had highly elevated blood lead levels and clinical symptoms associated with elevated blood lead levels. Conclusion. Workers in private SA shooting ranges are vulnerable to lead exposure and poisoning, and scaled-up action is required to protect them and their families, as well as shooting-range users, from lead and the related health risks.

  11. Atmospheric deposition study in the area of Kardzhali lead-zinc plant based on moss analysis

    International Nuclear Information System (INIS)

    Hristozova, G.; Marinova, S.; Strelkova, L.P.; Goryajnova, Z.; Frontas'eva, M.V.; Stafilov, T.

    2015-01-01

    For the first time the moss biomonitoring technique was used to assess the environmental situation in the area affected by the lead-zinc plant as one of the most hazardous enterprises in Bulgaria. 77 Hypnum cupressiforme moss samples were collected in the Kardzhali municipality in the summer and autumn of 2011. The concentrations of a total of 47 elements were determined by means of instrumental epithermal neutron activation analysis (ENAA), atomic absorption spectrometry (AAS) and inductively coupled plasma-atomic emission spectrometry (ICP-AES). Multivariate statistics was applied to characterize the sources of elements detected in the samples. Four groups of elements were found. In comparison to the data averaged for the area outside of the town, the atmospheric deposition loads for the elements of industrial origin in Kardzhali, where the smelter chimney is located, were found to be much higher. Median levels of the measured concentrations of the most toxic metals (Pb, Zn, Cd, As, Cu, In, Sb) were extremely high in this hot spot when compared to the median Bulgarian cross-country data from the 2010-2011 European moss survey. GIS technology was used to produce element distribution maps illustrating deposition patterns of element pollutants in the study area. The results obtained contribute to the Bulgarian environmental research used to study and control the manufacturing processes of the lead-zinc plant in the town of Kardzhali.

  12. A longitudinal study of the effects of long-term exposure to lead among lead battery factory workers in Taiwan (1989-1999)

    Energy Technology Data Exchange (ETDEWEB)

    Hsiao, Chun-Yin; Wu, Hong-Dar Isaac; Lai, Jim-Shoung; Kuo, Hsien-Wen [Institute of Environmental Health, China Medical College, No 91, Hsueh-Shin Rd., Taichung, Taiwan (China)

    2001-11-12

    The objective of this study was to assess the relationship between blood-lead levels (BLL), hematological, liver and renal indicators among workers in a lead battery factory in Taiwan over a 10-year period. Blood samples were taken periodically from 30 workers and BLL, HGB (hemoglobin), RBC (red blood cells), WBC (white blood cells) and HCT (hematocrit) were measured. Levels of GPT (alanine aminotransferase) and Crea (creatinine) in the blood were assessed to indicate liver and renal function, respectively. The results showed that there was a general decrease in BLL over the 10-year period (except for 1993). There was a similar trend for HCT, RBC and Crea. There was no significant trend for the other health indicators. Four generalized estimating equation (GEE) models [correlation model (A), threshold correlation model (B), instant change model (C) and lag change model (D)] were set up to demonstrate the causal relationship between BLL and the other health indicators. Models A and C showed that BLL correlated positively with RBC, but negatively with Crea. Model B showed that BLL correlated positively with GPT. There were no significant correlations of BLL with the other indicators. Models C and D, (GEE with logit link function to analyze the association between changes BLL and the other health indicators) showed that when BLL increased, RBC and HCT increased, both longitudinally and cross-sectionally. The authors conclude that long-term exposure to lead stimulates production of RBC and HCT, but the effect on liver and renal function was unclear.

  13. Developing a synthetic national population to investigate the impact of different cardiovascular disease risk management strategies: A derivation and validation study

    Science.gov (United States)

    Jackson, Rod

    2017-01-01

    Background Many national cardiovascular disease (CVD) risk factor management guidelines now recommend that drug treatment decisions should be informed primarily by patients’ multi-variable predicted risk of CVD, rather than on the basis of single risk factor thresholds. To investigate the potential impact of treatment guidelines based on CVD risk thresholds at a national level requires individual level data representing the multi-variable CVD risk factor profiles for a country’s total adult population. As these data are seldom, if ever, available, we aimed to create a synthetic population, representing the joint CVD risk factor distributions of the adult New Zealand population. Methods and results A synthetic population of 2,451,278 individuals, representing the actual age, gender, ethnicity and social deprivation composition of people aged 30–84 years who completed the 2013 New Zealand census was generated using Monte Carlo sampling. Each ‘synthetic’ person was then probabilistically assigned values of the remaining cardiovascular disease (CVD) risk factors required for predicting their CVD risk, based on data from the national census national hospitalisation and drug dispensing databases and a large regional cohort study, using Monte Carlo sampling and multiple imputation. Where possible, the synthetic population CVD risk distributions for each non-demographic risk factor were validated against independent New Zealand data sources. Conclusions We were able to develop a synthetic national population with realistic multi-variable CVD risk characteristics. The construction of this population is the first step in the development of a micro-simulation model intended to investigate the likely impact of a range of national CVD risk management strategies that will inform CVD risk management guideline updates in New Zealand and elsewhere. PMID:28384217

  14. Temporal Decorrelation Effect in Carbon Stocks Estimation Using Polarimetric Interferometry Synthetic Aperture Radar (PolInSAR (Case Study: Southeast Sulawesi Tropical Forest

    Directory of Open Access Journals (Sweden)

    Laode M Golok Jaya

    2017-07-01

    Full Text Available This paper was aimed to analyse the effect of temporal decorrelation in carbon stocks estimation. Estimation of carbon stocks plays important roles particularly to understand the global carbon cycle in the atmosphere regarding with climate change mitigation effort. PolInSAR technique combines the advantages of Polarimetric Synthetic Aperture Radar (PolSAR and Interferometry Synthetic Aperture Radar (InSAR technique, which is evidenced to have significant contribution in radar mapping technology in the last few years. In carbon stocks estimation, PolInSAR provides information about vertical vegetation structure to estimate carbon stocks in the forest layers. Two coherence Synthetic Aperture Radar (SAR images of ALOS PALSAR full-polarimetric with 46 days temporal baseline were used in this research. The study was carried out in Southeast Sulawesi tropical forest. The research method was by comparing three interferometric phase coherence images affected by temporal decorrelation and their impacts on Random Volume over Ground (RvoG model. This research showed that 46 days temporal baseline has a significant impact to estimate tree heights of the forest cover where the accuracy decrease from R2=0.7525 (standard deviation of tree heights is 2.75 meters to R2=0.4435 (standard deviation 4.68 meters and R2=0.3772 (standard deviation 3.15 meters respectively. However, coherence optimisation can provide the best coherence image to produce a good accuracy of carbon stocks.

  15. Genomics-Based Discovery of Plant Genes for Synthetic Biology of Terpenoid Fragrances: A Case Study in Sandalwood oil Biosynthesis.

    Science.gov (United States)

    Celedon, J M; Bohlmann, J

    2016-01-01

    Terpenoid fragrances are powerful mediators of ecological interactions in nature and have a long history of traditional and modern industrial applications. Plants produce a great diversity of fragrant terpenoid metabolites, which make them a superb source of biosynthetic genes and enzymes. Advances in fragrance gene discovery have enabled new approaches in synthetic biology of high-value speciality molecules toward applications in the fragrance and flavor, food and beverage, cosmetics, and other industries. Rapid developments in transcriptome and genome sequencing of nonmodel plant species have accelerated the discovery of fragrance biosynthetic pathways. In parallel, advances in metabolic engineering of microbial and plant systems have established platforms for synthetic biology applications of some of the thousands of plant genes that underlie fragrance diversity. While many fragrance molecules (eg, simple monoterpenes) are abundant in readily renewable plant materials, some highly valuable fragrant terpenoids (eg, santalols, ambroxides) are rare in nature and interesting targets for synthetic biology. As a representative example for genomics/transcriptomics enabled gene and enzyme discovery, we describe a strategy used successfully for elucidation of a complete fragrance biosynthetic pathway in sandalwood (Santalum album) and its reconstruction in yeast (Saccharomyces cerevisiae). We address questions related to the discovery of specific genes within large gene families and recovery of rare gene transcripts that are selectively expressed in recalcitrant tissues. To substantiate the validity of the approaches, we describe the combination of methods used in the gene and enzyme discovery of a cytochrome P450 in the fragrant heartwood of tropical sandalwood, responsible for the fragrance defining, final step in the biosynthesis of (Z)-santalols. © 2016 Elsevier Inc. All rights reserved.

  16. The improved biological response of shark tooth bioapatites in a comparative in vitro study with synthetic and bovine bone grafts.

    Science.gov (United States)

    López-Álvarez, M; Pérez-Davila, S; Rodríguez-Valencia, C; González, P; Serra, J

    2016-06-07

    Autologous bone is considered to be the gold standard for bone tissue regeneration, providing more highly efficient functional responses compared to synthetic materials, and avoiding the rejection risks of allogenic grafts. However, it presents limitations for certain types of surgery due to its high resorption levels and donor site morbidity. Different biphasic synthetic composites, based onnon-apatitic calcium phosphates enriched with apatitic phases-such as hydroxyapatite, and bioderived bone grafts of bovine and porcine origin-are proposed as lower resorption materials due to their higher crystalline structure. The present work proposes two new sources of bioapatites for bone filler applications obtained from the dentine and enameloid of shark teeth, respectively. These bioapatites each present a characteristic apatite-based composition and additional enrichments of specific trace elements, such as magnesium and fluorine, with proven roles in bone metabolism. Their processing and physicochemical characterization (SEM, FT-Raman and XRD) is presented, together with an in vitro evaluation of osteogenic activity compared to a commercial bovine mineralized matrix and synthetic HA/β TCP grafts. The results proved the globular morphology (0.5-1.5 μm) and porosity (~50 μm and ~0.5-1 μm) of shark dentine bioapatites with biphasic composition: apatitic (hydroxyapatite and apatite-(CaF)), non-apatitic (whitlockite), and an apatitic phase (fluorapatite), organized in oriented crystals in enameloid bioapatites. An evaluation of the pre-osteoblast MC3T3-E1 morphology revealed the colonization of pores in dentine bioapatites and an aligned cell growth in the oriented enameloid crystals. A higher proliferation (p  aligned fluorapatite crystals of enameloid bioapatites in promoting greater osteogenic activity was confirmed with a significantly increased ALP synthesis (p  <  0.01) compared to the commercial grafts.

  17. [From synthetic biology to synthetic humankind].

    Science.gov (United States)

    Nouvel, Pascal

    2015-01-01

    In this paper, we propose an historical survey of the expression "synthetic biology" in order to identify its main philosophical components. The result of the analysis is then used to investigate the meaning of the notion of "synthetic man". It is shown that both notions share a common philosophical background that can be summed up by the short but meaningful assertion: "biology is technology". The analysis allows us to distinguish two notions that are often confused in transhumanist literature: the notion of synthetic man and the notion of renewed man. The consequences of this crucial distinction are discussed. Copyright © 2015 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  18. Adsorption Studies of Lead by Enteromorpha Algae and Its Silicates Bonded Material

    Directory of Open Access Journals (Sweden)

    Hassan H. Hammud

    2014-01-01

    Full Text Available Lead adsorption by green Enteromorpha algae was studied. Adsorption capacity was 83.8 mg/g at pH 3.0 with algae (E and 1433.5 mg/g for silicates modified algae (EM. FTIR and thermal analysis of algae materials were studied. Thomas and Yoon-Nelson column model were best for adsorbent (E and algae after reflux (ER and Yan model for (EM with capacity 76.2, 71.1, and 982.5 mg/g, respectively. (ER and (EM show less swelling and better flow rate control than (E. Nonlinear methods are more appropriate technique. Error function calculations proved valuable for predicting the best adsorption isotherms, kinetics, and column models.

  19. Discovery of dihydrochalcone as potential lead for Alzheimer's disease: in silico and in vitro study.

    Directory of Open Access Journals (Sweden)

    Man Hoang Viet

    Full Text Available By the virtual screening method we have screened out Dihydrochalcone as a top-lead for the Alzheimer's disease using the database of about 32364 natural compounds. The binding affinity of this ligand to amyloid beta (Aβ fibril has been thoroughly studied by computer simulation and experiment. Using the Thioflavin T (ThT assay we have obtained the inhibition constant IC50 μM. This result is in good agreement with the estimation of the binding free energy obtained by the molecular mechanic-Poisson Boltzmann surface area method and all-atom simulation with the force field CHARMM 27 and water model TIP3P. Cell viability assays indicated that Dihydrochalcone could effectively reduce the cytotoxicity induced by Aβ. Thus, both in silico and in vitro studies show that Dihydrochalcone is a potential drug for the Alzheimers disease.

  20. Synthetic Cathinones ("Bath Salts")

    Science.gov (United States)

    ... cathinones? Behavioral therapy can be used to treat addiction to synthetic cathinones. Examples include: cognitive-behavioral therapy contingency management, or motivational incentives—providing rewards to ...

  1. Recent studies on radiation damage formation in synthetic NaCl and natural rock salt for radioactive waste disposal applications

    International Nuclear Information System (INIS)

    Swyler, K.J.; Klaffky, R.W.; Levy, P.W.

    1980-01-01

    Radiation damage formation in natural rock salt is described as a function of irradiation temperature and plastic deformation. F-center formation decreases with increasing temperature while significant colloidal sodium formation occurs over a restricted temperature range around 150 0 C. Plastic deformation increases colloid formation; it is estimated that colloid concentrations may be increased by a factor of 3 if the rock salt near radioactive waste disposal canisters is heavily deformed. Optical bandshape analysis indicates systematic differences between the colloids formed in synthetic and natural rock salts

  2. Study on homogenization of synthetic GNSS-retrieved IWV time series and its impact on trend estimates with autoregressive noise

    Science.gov (United States)

    Klos, Anna; Pottiaux, Eric; Van Malderen, Roeland; Bock, Olivier; Bogusz, Janusz

    2017-04-01

    A synthetic benchmark dataset of Integrated Water Vapour (IWV) was created within the activity of "Data homogenisation" of sub-working group WG3 of COST ES1206 Action. The benchmark dataset was created basing on the analysis of IWV differences retrieved by Global Positioning System (GPS) International GNSS Service (IGS) stations using European Centre for Medium-Range Weather Forecats (ECMWF) reanalysis data (ERA-Interim). Having analysed a set of 120 series of IWV differences (ERAI-GPS) derived for IGS stations, we delivered parameters of a number of gaps and breaks for every certain station. Moreover, we estimated values of trends, significant seasonalities and character of residuals when deterministic model was removed. We tested five different noise models and found that a combination of white and autoregressive processes of first order describes the stochastic part with a good accuracy. Basing on this analysis, we performed Monte Carlo simulations of 25 years long data with two different types of noise: white as well as combination of white and autoregressive processes. We also added few strictly defined offsets, creating three variants of synthetic dataset: easy, less-complicated and fully-complicated. The 'Easy' dataset included seasonal signals (annual, semi-annual, 3 and 4 months if present for a particular station), offsets and white noise. The 'Less-complicated' dataset included above-mentioned, as well as the combination of white and first order autoregressive processes (AR(1)+WH). The 'Fully-complicated' dataset included, beyond above, a trend and gaps. In this research, we show the impact of manual homogenisation on the estimates of trend and its error. We also cross-compare the results for three above-mentioned datasets, as the synthetized noise type might have a significant influence on manual homogenisation. Therefore, it might mostly affect the values of trend and their uncertainties when inappropriately handled. In a future, the synthetic dataset

  3. Synthetic biology, metaphors and responsibility.

    Science.gov (United States)

    McLeod, Carmen; Nerlich, Brigitte

    2017-08-29

    Metaphors are not just decorative rhetorical devices that make speech pretty. They are fundamental tools for thinking about the world and acting on the world. The language we use to make a better world matters; words matter; metaphors matter. Words have consequences - ethical, social and legal ones, as well as political and economic ones. They need to be used 'responsibly'. They also need to be studied carefully - this is what we want to do through this editorial and the related thematic collection. In the context of synthetic biology, natural and social scientists have become increasingly interested in metaphors, a wave of interest that we want to exploit and amplify. We want to build on emerging articles and books on synthetic biology, metaphors of life and the ethical and moral implications of such metaphors. This editorial provides a brief introduction to synthetic biology and responsible innovation, as well as a comprehensive review of literature on the social, cultural and ethical impacts of metaphor use in genomics and synthetic biology. Our aim is to stimulate an interdisciplinary and international discussion on the impact that metaphors can have on science, policy and publics in the context of synthetic biology.

  4. Study on Leading Vehicle Detection at Night Based on Multisensor and Image Enhancement Method

    Directory of Open Access Journals (Sweden)

    Mei Chen

    2016-01-01

    Full Text Available Low visibility is one of the reasons for rear accident at night. In this paper, we propose a method to detect the leading vehicle based on multisensor to decrease rear accidents at night. Then, we use image enhancement algorithm to improve the human vision. First, by millimeter wave radar to get the world coordinate of the preceding vehicles and establish the transformation of the relationship between the world coordinate and image pixels coordinate, we can convert the world coordinates of the radar target to image coordinate in order to form the region of interesting image. And then, by using the image processing method, we can reduce interference from the outside environment. Depending on D-S evidence theory, we can achieve a general value of reliability to test vehicles of interest. The experimental results show that the method can effectively eliminate the influence of illumination condition at night, accurately detect leading vehicles, and determine their location and accurate positioning. In order to improve nighttime driving, the driver shortage vision, reduce rear-end accident. Enhancing nighttime color image by three algorithms, a comparative study and evaluation by three algorithms are presented. The evaluation demonstrates that results after image enhancement satisfy the human visual habits.

  5. What motivates occasional faculty developers to lead faculty development workshops? A qualitative study.

    Science.gov (United States)

    O'Sullivan, Patricia S; Irby, David M

    2015-11-01

    The demand for faculty development is ongoing, and many medical schools will need to expand their pool of faculty developers to include physicians and scientists whose primary expertise is not education. Insight into what motivates occasional faculty developers can guide recruitment and retention strategies. This study was designed to understand the motivations of faculty developers who occasionally (one to three times each year) lead faculty development workshops. Qualitative data were collected in March and April 2012 from interviews with faculty developers who occasionally taught workshops from 2007 to 2012 in the University of California, San Francisco, School of Medicine's faculty development program. The interviews were audiotaped and transcribed. The authors thematically analyzed the transcripts using a general inductive approach and developed codes sensitized by motivation theories. The authors interviewed 29/30 (97%) occasional faculty developers and identified five themes: mastery (desire to learn and develop professionally), relatedness (enjoyment of working with and learning from others), duty (sense of obligation to give back and be a good academic citizen), purpose (commitment to improving local teaching and ultimately patient care), and satisfaction (fun and enjoyment). Four of the themes the authors found are well addressed in motivation theory literature: mastery, relatedness, duty, and purpose. Whereas these four are motivators for occasional faculty developers, it is the fifth theme-satisfaction-that the authors feel is foundational and links the others together. Armed with this understanding, individuals leading faculty development programs can develop strategies to recruit and retain occasional faculty developers.

  6. Pharmacological and spectral studies of synthetic biomimetic copper complexes derived from 3-hydroxyflavone derivatives as anti-inflammatory agents

    Directory of Open Access Journals (Sweden)

    K. Nagashri

    2016-09-01

    Full Text Available Novel biomimetic ligands were synthesized by the condensation of 3-hydroxyflavone, 2-aminophenol(L1/2-aminobenzoic acid (L2 and-aminothiazole (L3. Their Cu(II complexes have also been synthesized and characterized on the basis of 1H NMR, IR, UV–Vis spectra, elemental analyses, molar conductivity, ESR, electrochemical behaviour and thermal analyses. The antimicrobial activities (MIC values of the ligands, copper complexes and standard drugs have been evaluated using the serial dilution technique against the bacterial species Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Proteus vulgaris and Pseudomonas aeruginosa and fungal species Aspergillus niger, Rhizopus stolonifer, Aspergillus flavus, Rhizoctonia bataicola and Candida albicans. The anti-inflammatory and SOD activities of the investigated compounds are also promising and allow the selection of a lead compound for further biological studies.

  7. Engineering Ecosystems and Synthetic Ecologies#

    Science.gov (United States)

    Mee, Michael T; Wang, Harris H

    2012-01-01

    Microbial ecosystems play an important role in nature. Engineering these systems for industrial, medical, or biotechnological purposes are important pursuits for synthetic biologists and biological engineers moving forward. Here, we provide a review of recent progress in engineering natural and synthetic microbial ecosystems. We highlight important forward engineering design principles, theoretical and quantitative models, new experimental and manipulation tools, and possible applications of microbial ecosystem engineering. We argue that simply engineering individual microbes will lead to fragile homogenous populations that are difficult to sustain, especially in highly heterogeneous and unpredictable environments. Instead, engineered microbial ecosystems are likely to be more robust and able to achieve complex tasks at the spatial and temporal resolution needed for truly programmable biology. PMID:22722235

  8. Quantifying lead-time bias in risk factor studies of cancer through simulation.

    Science.gov (United States)

    Jansen, Rick J; Alexander, Bruce H; Anderson, Kristin E; Church, Timothy R

    2013-11-01

    Lead-time is inherent in early detection and creates bias in observational studies of screening efficacy, but its potential to bias effect estimates in risk factor studies is not always recognized. We describe a form of this bias that conventional analyses cannot address and develop a model to quantify it. Surveillance Epidemiology and End Results (SEER) data form the basis for estimates of age-specific preclinical incidence, and log-normal distributions describe the preclinical duration distribution. Simulations assume a joint null hypothesis of no effect of either the risk factor or screening on the preclinical incidence of cancer, and then quantify the bias as the risk-factor odds ratio (OR) from this null study. This bias can be used as a factor to adjust observed OR in the actual study. For this particular study design, as average preclinical duration increased, the bias in the total-physical activity OR monotonically increased from 1% to 22% above the null, but the smoking OR monotonically decreased from 1% above the null to 5% below the null. The finding of nontrivial bias in fixed risk-factor effect estimates demonstrates the importance of quantitatively evaluating it in susceptible studies. Copyright © 2013 Elsevier Inc. All rights reserved.

  9. Performance of dedicated versus integrated bipolar defibrillator leads with CRT-defibrillators: results from a Prospective Multicenter Study.

    Science.gov (United States)

    Freedman, Roger A; Petrakian, Alex; Boyce, Ker; Haffajee, Charles; Val-Mejias, Jesus E; Oza, Ashish L

    2009-02-01

    Right ventricular (RV) anodal stimulation may occur in cardiac resynchronization therapy defibrillators (CRT-D) when left ventricular (LV) pacing is configured between the LV lead and an electrode on the RV defibrillator lead. RV defibrillator leads can have a dedicated proximal pacing ring electrode (dedicated bipolar) or utilize the distal shocking coil as the proximal pacing electrode (integrated bipolar). This study compares the performance of integrated versus dedicated leads with respect to anodal stimulation incidence, sensing, and inappropriate ventricular tachyarrhythmia detection in patients implanted with CRT-D. Two hundred ninety-two patients were randomly assigned to receive dedicated or integrated bipolar RV leads at the time of CRT-D implantation. Patients were followed for 6 months. Patients with dedicated bipolar RV leads exhibited markedly higher rates of anodal stimulation than did patients with integrated leads. The incidence of anodal stimulation was 64% at implant for dedicated bipolar RV leads compared to 1% for integrated bipolar RV leads. The likelihood of anodal stimulation in patients with dedicated leads fell progressively during the 6-month follow-up (51.5%), but always exceeded the incidence of anodal stimulation in patients with integrated leads (5%). Clinically detectable undersensing and oversensing were very unusual and did not differ significantly between lead designs. There were no inappropriate ventricular tachyarrhythmia detections for either lead type. Integrated bipolar RV defibrillator leads had a significantly lower incidence of RV anodal stimulation when compared to dedicated bipolar RV defibrillation leads, with no clinically detectable oversensing or undersensing, and with no inappropriate ventricular tachyarrhythmia detections for either lead type.

  10. Visualization and Studies of Ion-Diffusion Kinetics in Cesium Lead Bromide Perovskite Nanowires.

    Science.gov (United States)

    Pan, Dongxu; Fu, Yongping; Chen, Jie; Czech, Kyle J; Wright, John C; Jin, Song

    2018-03-14

    The facile chemical transformation of metal halide perovskites via ion exchange has been attributed to their "soft" crystal lattices that enable fast ion migration. Kinetic studies of such processes could provide mechanistic insights on the ion migration dynamics. Herein, by using aligned single-crystal nanowires of cesium lead bromide (CsPbBr 3 ) perovskite on epitaxial substrates as platforms, we visualize and investigate the cation or anion interdiffusion kinetics via spatially resolved photoluminescence measurement on heterostructures fabricated by stacking CsPbCl 3 , MAPbI 3 , or MAPbBr 3 microplates on top of CsPbBr 3 nanowires. Time-dependent confocal photoluminescence microscopy and energy-dispersive X-ray spectroscopy showed the solid-state anion interdiffusion readily occurs to result in halide concentration gradients along CsPbBr 3-3 x Cl 3 x ( x = 0-1) nanowires. Quantitative analysis of such composition profiles using Fick's law allowed us, for the first time, to extract interdiffusion coefficients of the chloride-bromide couple and an activation energy of 0.44 ± 0.02 eV for ion diffusion from temperature-dependent studies. In contrast, iodide-bromide interdiffusion is limited, likely due to the complex phase behaviors of mixed alloys of CsPb(Br,I) 3 . In contrast to the relatively mobile anions, A-site cation interdiffusion across the MAPbBr 3 /CsPbBr 3 junctions was barely observed at room temperature. Our results present a general method to investigate the kinetics of the solid-state ion migration, and the gained insights on ion diffusion can provide guidelines for rationally designing perovskite heterostructures that could lead to new properties for fundamental studies and technological applications.

  11. Studies on cluster decay from trans-lead nuclei using different versions of nuclear potentials

    Energy Technology Data Exchange (ETDEWEB)

    Santhosh, K.P.; Sukumaran, Indu [Kannur University, School of Pure and Applied Physics, Payyanur, Kerala (India)

    2017-06-15

    The cluster decays from various isotopes of trans-lead nuclei have been studied using 12 different nuclear potentials by evaluating decay half-lives and are then compared with the available experimental data. The study has shown that the barrier penetrability as well as the decay half-lives varies with the nuclear potential used. The standard deviation of the estimated half-lives is also calculated for these twelve nuclear potentials in comparison with the experimental data. The potential Bass 1980 is found to be the most appropriate potential for studying cluster radioactivity as the standard deviation obtained is least. Among the different proximity potential versions; proximity 1977, proximity 1988, proximity 2000, and modified proximity 2000, the minimum standard deviation is for proximity 1988. The Geiger-Nuttall (G-N) plots studied for different cluster emissions from various parents are observed to show linear behavior but with different slopes and intercepts. Again, the G-N plots obtained are linear with different slopes and intercepts when plotted for different nuclear potentials. So it is observed that with the inclusion of different nuclear potentials, the linearity of the G-N plot remains unaltered. Irrespective of the nuclear potential used, the universal curve (log{sub 10}T{sub 1/2} vs. -ln P) studied for various clusters emitted from various parents are obtained as linear with same slope and intercept. (orig.)

  12. The Identification and Synthesis of Lead Apatite Minerals Formed in Lead Water Pipes

    Directory of Open Access Journals (Sweden)

    Jeremy D. Hopwood

    2016-01-01

    Full Text Available Phosphate is added to drinking water in the UK to minimise the release of lead from lead water pipes. The phosphate encourages the formation of insoluble lead apatites on the walls of the pipe. Hydroxylpyromorphite Pb5(PO43OH is the lead apatite that is most often used to model lead levels in tap water; however, its presence has not been confirmed. Our aims were to identify the lead pipe apatite and synthesise it. The synthetic mineral would then be used in future solubility studies to produce better predictions of lead levels in tap water. XRD and FTIR were used to characterise the minerals on a range of lead pipes. Pyromorphite and hydroxylpyromorphite were absent and instead a range of mixed calcium lead apatites were present. For every five lead ions in the general formula Pb5(PO43X between one and two ions were replaced with calcium and there was evidence of substitution of PO43- by either CO32- or HPO42-. Calcium lead apatites with similar unit cell dimensions to those found on lead water pipes were then synthesised. The calcium : lead ratio in these reaction mixtures was in excess of 500 : 1 and the resulting crystals were shown by TEM to be nanosized rods and flakes. The synthetic apatites that most closely resembled the unit cell dimensions of the apatites on lead water pipes were shown to be Pb3.4Ca1.3(PO43Cl0.03OH0.97, Pb3.6Ca1.2(PO43Cl0.07OH0.93, and Pb3.6Ca1.2(PO43Cl0.27OH0.73.

  13. Synthesis and Structural Studies of Er3+ Containing Lead Cadmium Fluoroborate Glasses and Glass-Ceramics

    Directory of Open Access Journals (Sweden)

    Silva Maurício A.P.

    2002-01-01

    Full Text Available The vitreous domain was established in the PbF2-CdF2-B2O 3 system from melting and quenching experiments. Er3+ containing glasses were prepared and glass ceramics were obtained by selected heat-treatments. Lead fluoride was identified (beta-PbF2 as the crystalline phase. Structural studies were performed in some glassy and partially crystallized samples by means of X-ray Diffraction (XRD and Extended X-ray Absorption Fine Structure (EXAFS measurements. The role of Cd2+ and Pb2+ atoms on the glass network formation and also on the crystallization behavior was put forward by these techniques. After crystallization Er3+ atoms segregated in the crystal phase.

  14. A study on dietary habits, health related lifestyle, blood cadmium and lead levels of college students.

    Science.gov (United States)

    Shin, Nari; Hyun, Whajin; Lee, Hongmie; Ro, Mansoo; Song, Kyunghee

    2012-08-01

    This study was performed in order to investigate dietary habits, health related lifestyle and blood cadmium and lead levels in female college students. 80 college students (43 males and 37 females) participated in the survey questionnaires. Body weight and height, blood pressure, and body composition were measured. The systolic blood pressure of male and female students were 128.9 ± 13.9 and 109.8 ± 12.0, respectively. The diastolic blood pressure of male and female students were 77.1 ± 10.3 and 66.0 ± 6.9, respectively, showing that male students had significantly higher blood pressure than female students (P habits score of female students was significantly higher than that of male students (P improve their dietary and health related living habits.

  15. Study of beauty quark production and next-to-leading order at HERA

    Energy Technology Data Exchange (ETDEWEB)

    Nuncio Quiroz, Adriana Elizabeth

    2008-08-15

    In this thesis a study on the production and evolution of beauty quarks in ep collisions at HERA is presented. The emphasis is put on the corresponding Quantum Chromodynamics predictions including next-to-leading order corrections. In the context of this work the FMNR x Pythia interface was developed, which calculates next-to-leading order Quantum Chromodynamics predictions at visible level for heavy-flavour processes in the photoproduction regime. This is achieved using the RedStat routines which transform the FMNR program into a Monte Carlo-like event generator. The parton-level events obtained are interfaced to Pythia using the Le Houches accord routines. All branching ratios and decay channels of the heavy quarks implemented in the Pythia framework are used, and therefore complex cuts on the nal state can be applied. The FMNR x Pythia interface is applied in this thesis to obtain next-to-leading order predictions for the recently finished heavy flavour ZEUS analyses: the ep {yields} b anti bX {yields} D{sup *}{mu}X' and ep {yields} b anti bX {yields} {mu}{sup +}{mu}{sup -}X' channels. A comparison with the H1 D{sup *}{mu} measurement is also performed. Since the use of such double tagging techniques to identify events where heavy flavours are present proved to be very convenient when the nal state is a pair of leptons, another part of this thesis work deals with the implementation of an electron finder, the {sup G}Elec finder. This finder is tested on the reconstruction of the J/{psi} {yields} e{sup +}e{sup -} signal. Finally, a heavy-flavour analysis has been started, namely the ep {yields} b anti bX {yields} e{mu}X' dilepton channel, using an integrated luminosity of 114 pb{sup -1} gated by the ZEUS detector in the years 1996-2000. Compared to previous analyses the study of beauty quark production in this channel extends the phase space of the measurement closer to the kinematic threshold, since electrons provide access to lower p{sub T} values

  16. Study of beauty quark production and next-to-leading order effects at HERA

    International Nuclear Information System (INIS)

    Nuncio Quiroz, Adriana Elizabeth

    2008-08-01

    In this thesis a study on the production and evolution of beauty quarks in ep collisions at HERA is presented. The emphasis is put on the corresponding Quantum Chromodynamics predictions including next-to-leading order corrections. In the context of this work the FMNR x Pythia interface was developed, which calculates next-to-leading order Quantum Chromodynamics predictions at visible level for heavy-flavour processes in the photoproduction regime. This is achieved using the RedStat routines which transform the FMNR program into a Monte Carlo-like event generator. The parton-level events obtained are interfaced to Pythia using the Le Houches accord routines. All branching ratios and decay channels of the heavy quarks implemented in the Pythia framework are used, and therefore complex cuts on the nal state can be applied. The FMNR x Pythia interface is applied in this thesis to obtain next-to-leading order predictions for the recently finished heavy flavour ZEUS analyses: the ep → b anti bX → D * μX' and ep → b anti bX → μ + μ - X' channels. A comparison with the H1 D * μ measurement is also performed. Since the use of such double tagging techniques to identify events where heavy flavours are present proved to be very convenient when the nal state is a pair of leptons, another part of this thesis work deals with the implementation of an electron finder, the G Elec finder. This finder is tested on the reconstruction of the J/ψ → e + e - signal. Finally, a heavy-flavour analysis has been started, namely the ep → b anti bX → eμX' dilepton channel, using an integrated luminosity of 114 pb -1 gated by the ZEUS detector in the years 1996-2000. Compared to previous analyses the study of beauty quark production in this channel extends the phase space of the measurement closer to the kinematic threshold, since electrons provide access to lower p T values than muons do. The technical part of this thesis consisted in the calibration, maintenance and data

  17. Regional lead isotope study of a polluted river catchment: River Wear, Northern England, UK

    International Nuclear Information System (INIS)

    Shepherd, Thomas J.; Chenery, Simon R.N.; Pashley, Vanessa; Lord, Richard A.; Ander, Louise E.; Breward, Neil; Hobbs, Susan F.; Horstwood, Matthew; Klinck, Benjamin A.; Worrall, Fred

    2009-01-01

    High precision, lead isotope analyses of archived stream sediments from the River Wear catchment, northeast England (1986-88), provide evidence for three main sources of anthropogenic lead pollution; lead mining, industrial lead emissions and leaded petrol. In the upper catchment, pollution is totally controlled and dominated by large lead discharges from historic mining centres in the North Pennine Orefield ( 208 Pb/ 206 Pb, 207 Pb/ 206 Pb ratios range from 2.0744-2.0954 and 0.8413-0.8554 respectively). In the lower catchment, co-extensive with the Durham Coalfield and areas of high population density, pollution levels are lower and regionally more uniform. Isotope ratios are systematically higher than in the upper catchment ( 208 Pb/ 206 Pb, 207 Pb/ 206 Pb ratios range from 2.0856-2.1397 and 0.8554-0.8896 respectively) and far exceed values determined for the geogenic regional background. Here, the pollution is characterised by the atmospheric deposition of industrial lead and petrol lead. Lead derived from the combustion of coal, although present, is masked by the other two sources. Recent sediments from the main channel of the River Wear are isotopically indistinguishable from older, low order stream sediments of the North Pennine Orefield, indicating that contamination of the river by lead mining waste (up to several 1000 mg/kg Pb at some locations) continues to pose an environmental problem; a pattern that can be traced all the way to the tidal reach. Using within-catchment isotope variation and sediment lead concentrations, estimates can be made of the discharges from discrete mines or groups of mines to the overall level of lead pollution in the River Wear. As well as providing information pertinent to source apportionment and on-going catchment remediation measures, the database is a valuable resource for epidemiologists concerned with the health risks posed by environmental lead.

  18. Comparative study for "36 V" vehicle applications: advantages of lead-acid batteries

    Science.gov (United States)

    Lailler, Patrick; Sarrau, Jean-François; Sarrazin, Christian

    From thermal engine equipped vehicles to completely electric ones, evolution of light weight vehicles in the future will take several steps in so far as there is no adequate battery or fuel cell presently available to power these vehicles for "on the road" driving. On the other hand, for city driving, vehicles can be improved a lot in terms of fuel efficiency as well as air pollution, if partly or totally electric propulsion can be developed, manufactured and marketed for appropriate applications. The 36-42 V battery is part of this orientation towards improving the efficiency of thermal vehicles in city driving, while keeping adequate autonomy on the roads. Actually, in city traffic, thermal engines are idle most of the time and stop periods represent a large part of the time spent "driving", using up fuel and polluting air for no use at all. The idea of stopping the engine during these periods, if appropriately managed, might potentially lead to a large improvement in fuel economy as well as air pollution reduction. The association of a higher voltage battery to an alternator-starter device in thermal vehicles, seems to be an interesting way towards that end. In this paper, we are presenting our results of a study we have just completed in relationship with RENAULT & VALEO, supported by the French Ministry of Industry, concerning a comparative evaluation of different automobile energy storage systems, and the definition of specifications as the final step of this study. The main conclusion is that lead-acid will still remain dominant in this role, since its operational cost versus efficiency is by far the lowest of every battery presently considered, more particularly in the less expensive car segments.

  19. Synthesis of interpenetrating network hydrogel from poly(acrylic acid-co-hydroxyethyl methacrylate) and sodium alginate: modeling and kinetics study for removal of synthetic dyes from water.

    Science.gov (United States)

    Mandal, Bidyadhar; Ray, Samit Kumar

    2013-10-15

    Several interpenetrating network (IPN) hydrogels were made by free radical in situ crosslink copolymerization of acrylic acid (AA) and hydroxy ethyl methacrylate in aqueous solution of sodium alginate. N,N'-methylenebisacrylamide (MBA) was used as comonomer crosslinker for making these crosslink hydrogels. All of these hydrogels were characterized by carboxylic content, FTIR, SEM, XRD, DTA-TGA and mechanical properties. Swelling, diffusion and network parameters of the hydrogels were studied. These hydrogels were used for adsorption of two important synthetic dyes, i.e. Congo red and methyl violet from water. Isotherms, kinetics and thermodynamics of dye adsorption by these hydrogels were also studied. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Perspectives on the enablers of e-heath adoption: an international interview study of leading practitioners.

    Science.gov (United States)

    Moxham, Claire; Chambers, Naomi; Girling, Jeff; Garg, Shruti; Jelfs, Elizabeth; Bremner, Jeni

    2012-08-01

    Studies examining the application of information technology to the delivery of health-care services often highlight the anticipated benefits. In consequence, the benefits of health-care information technology adoption, often referred to as 'e-health', are widely reported yet there is limited empirical evidence as to how such benefits can be realized. Design and implementation guidelines have been considered from a socio-technical perspective and there is support for the successful application of these principles. There are also some global surveys on the topic, but these often report only statistical data and lack richness of content. This study draws on existing literature to examine whether the principles of health-care information technology adoption are currently applied in practice. The paper presents a timely international analysis of the drivers, critical enablers and successful deployment strategies for e-health from the perspective of leading practitioners. The study considers the adoption of e-health in 15 countries. A qualitative research design was used and semistructured interviews were conducted with 38 thought leaders with expertise in health-care information systems and technology. The study presents a comparative analysis of the lessons learned from implementing, integrating and embedding e-health in practice, and presents a four-phase approach from the perspective of practitioners for the accelerated deployment of e-health systems: (i) develop a strategic approach, (ii) engage the workforce, (iii) capitalize on information technology and (iv) partner with the patient/citizen.

  1. CFD study on NACA 4415 airfoil implementing spherical and sinusoidal Tubercle Leading Edge.

    Directory of Open Access Journals (Sweden)

    S M A Aftab

    Full Text Available The Humpback whale tubercles have been studied for more than a decade. Tubercle Leading Edge (TLE effectively reduces the separation bubble size and helps in delaying stall. They are very effective in case of low Reynolds number flows. The current Computational Fluid Dynamics (CFD study is on NACA 4415 airfoil, at a Reynolds number 120,000. Two TLE shapes are tested on NACA 4415 airfoil. The tubercle designs implemented on the airfoil are sinusoidal and spherical. A parametric study is also carried out considering three amplitudes (0.025c, 0.05c and 0.075c, the wavelength (0.25c is fixed. Structured mesh is utilized to generate grid and Transition SST turbulence model is used to capture the flow physics. Results clearly show spherical tubercles outperform sinusoidal tubercles. Furthermore experimental study considering spherical TLE is carried out at Reynolds number 200,000. The experimental results show that spherical TLE improve performance compared to clean airfoil.

  2. Quantum synthetic aperture radar

    Science.gov (United States)

    Lanzagorta, Marco; Jitrik, Oliverio; Uhlmann, Jeffrey; Venegas-Andraca, Salvador E.

    2017-05-01

    Synthetic aperture radar (SAR) uses sensor motion to generate finer spatial resolution of a given target area. In this paper we explore the theoretical potential of quantum synthetic aperture quantum radar (QSAR). We provide theoretical analysis and simulation results which suggest that QSAR can provide improved detection performance over classical SAR in the high-noise low-brightness regime.

  3. Designing synthetic biology.

    Science.gov (United States)

    Agapakis, Christina M

    2014-03-21

    Synthetic biology is frequently defined as the application of engineering design principles to biology. Such principles are intended to streamline the practice of biological engineering, to shorten the time required to design, build, and test synthetic gene networks. This streamlining of iterative design cycles can facilitate the future construction of biological systems for a range of applications in the production of fuels, foods, materials, and medicines. The promise of these potential applications as well as the emphasis on design has prompted critical reflection on synthetic biology from design theorists and practicing designers from many fields, who can bring valuable perspectives to the discipline. While interdisciplinary connections between biologists and engineers have built synthetic biology via the science and the technology of biology, interdisciplinary collaboration with artists, designers, and social theorists can provide insight on the connections between technology and society. Such collaborations can open up new avenues and new principles for research and design, as well as shed new light on the challenging context-dependence-both biological and social-that face living technologies at many scales. This review is inspired by the session titled "Design and Synthetic Biology: Connecting People and Technology" at Synthetic Biology 6.0 and covers a range of literature on design practice in synthetic biology and beyond. Critical engagement with how design is used to shape the discipline opens up new possibilities for how we might design the future of synthetic biology.

  4. Study on damage of DNA in mice induced by mercury cadmium and/or lead

    International Nuclear Information System (INIS)

    Hu Xiaopan; Zhou Jianhua; Shi Xijing; Yan Liping

    2004-01-01

    Objective: To explore the joint injury actions of mercury, cadmium and/or lead on DNA in peripheral blood lymphocytes of mice. Methods: The blood specimens were obtained from mice at the 2 day after the peritoneal injections. DNA damages were determined by single cell gel electrophoresis (SCGE) and 3 H-TdR incorporation. Results: Acquired by SCGE technique, tail movement of DNA in mercury-cadmium-lead group was significantly greater than that in the single exposure group, the difference was significant too between mercury-cadmium group and cadmium group, cadmium-lead group and cadmium group. The results of 3 H-TdR incorporation showed: the values of DPM in mercury-cadmium group and cadmium-lead group were lower than that in the single exposure group and the value of DPM lowered more significantly after exposure to mercury-cadmium-lead. Conclusion: The combined effects of mercury, cadmium, lead on DNA damage are more significant. (author)

  5. Research Protocol: Collections Related to Synthetic Turf ...

    Science.gov (United States)

    The “Federal Research Action Plan on Recycled Tire Crumb Used on Playing Fields and Playgrounds” (referred to subsequently as the Federal Research Action Plan or FRAP) was finalized in February 2016. The U.S. EPA and CDC/ATSDR, in collaboration with CPSC, have prepared this research protocol to implement portions of the research activities outlined under the FRAP. Specifically, this research protocol is designed to implement three of the research elements described in the Federal Research Action Plan: Conduct a literature review and data gaps analysis; Perform tire crumb rubber characterization research; Perform human exposure characterization research. Concerns have been raised by the public about the safety of recycled tire crumb rubber used in synthetic turf fields and playgrounds in the United States. Several studies have been identified that examine exposure to tire crumb rubber infill in these settings. While, in general, these studies have not provided evidence for these health concerns, the existing studies do not comprehensively evaluate all aspects of exposure associated with these use scenarios. Additional research is needed to help fill important data gaps that will lead to improved exposure assessment and risk evaluation for children and adults using synthetic turf fields and playgrounds with tire crumb rubber. In response, the U.S. Environmental Protection Agency (EPA), the Centers for Disease Control and Prevention/Agency for Toxic Su

  6. Immune function biomarkers in children exposed to lead and organochlorine compounds: a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Obi-Osius Nadia

    2005-04-01

    Full Text Available Abstract Background Different organochlorines and lead (Pb have been shown to have immunomodulating properties. Children are at greater risk for exposure to these environmental toxicants, but very little data exist on simultaneous exposures to these substances. Methods We investigated whether the organochlorine compounds (OC dichlorodiphenylethylene (DDE, hexachlorobenzene (HCB, hexachlorocyclohexane (γ-HCH, the sum of polychlorinated biphenyls (ΣPCBs and Pb were associated with immune markers such as immunoglobulin (Ig levels, white blood cell (WBC, counts of lymphocytes; eosinophils and their eosinophilic granula as well as IgE count on basophils. The investigation was part of a cross-sectional environmental study in Hesse, Germany. In 1995, exposure to OC and Pb were determined, questionnaire data collected and immune markers quantified in 331 children. For the analyses, exposure (OC and Pb concentrations were grouped in quartiles (γ-HCH into tertiles. Using linear regression, controlling for age, gender, passive smoking, serum lipids, and infections in the previous 12 months, we assessed the association between exposures and immune markers. Adjusted geometric means are provided for the different exposure levels. Results Geometric means were: DDE 0.32 μg/L, ΣPCBs 0.50 μg/L, HCB 0.22 μg/L, γ-HCH 0.02 μg/L and Pb 26.8 μg/L. The ΣPCBs was significantly associated with increased IgM levels, whereas HCB was inversely related to IgM. There was a higher number of NK cells (CD56+ with increased γ-HCH concentrations. At higher lead concentrations we saw increased IgE levels. DDE showed the most associations with significant increases in WBC count, in IgE count on basophils, IgE, IgG, and IgA levels. DDE was also found to significantly decrease eosinophilic granula content. Conclusion Low-level exposures to OC and lead (Pb in children may have immunomodulating effects. The increased IgE levels, IgE count on basophils, and the reduction of

  7. Predictors of elevated blood lead levels among 3-year-old Ukrainian children: a nested case-control study.

    Science.gov (United States)

    Friedman, L S; Lukyanova, O M; Kundiev, Y I; Shkiryak-Nizhnyk, Z A; Chislovska, N V; Mucha, A; Zvinchuk, A V; Oliynyk, I; Hryhorczuk, D

    2005-10-01

    Lead is common in the general population. However, data are lacking for the Ukraine and many other countries from the former Soviet Union (FSU). In this study we evaluate the level of blood lead among 212 Ukrainian children and determine predictors of elevated lead levels. We also describe the health effects associated with elevated blood lead. A nested case-control study from a prospective cohort of Ukrainian 3-year-old children was conducted in March 1998. Blood assays were analyzed for lead by labs at the Centers for Disease Control and using portable examination kits. We evaluated predictors of elevated blood lead (blood levels in the upper quartile >4.65 microg/dL) using a multivariable logistic regression model. The model included socioeconomic status, parent occupation, environmental tobacco smoke, hygiene, diet, and health status. The geometric mean lead level was 3.15 microg/dL (range, 0.7--22.7). In our adjusted model, we observed a strong association between lead levels in the upper quartile and children whose fathers worked manual labor jobs in industries associated with lead exposures [adjusted odds ratio (OR)=2.25; P=0.025] and mothers who smoke indoors (adjusted OR=2.87; P=0.047). Daily hygiene and dietary habits were not associated with elevated lead levels. No increased risks of overall morbidity or lead-associated illness were observed (anemia, dental caries, renal disease, cardiovascular diseases, and musculoskeletal complaints). This is the first study to describe lead levels and associated variables among Ukrainian children in the peer-reviewed literature. Elevated lead levels in these children were associated with paternal occupation and mothers smoking indoors. At age 3 no adverse health effects were observed. More data are needed to determine the level of heavy metal contamination in children from the Ukraine and many other former Soviet nation-states.

  8. Corrosion studies on copper and titanium-lead canisters for nuclear waste disposal

    International Nuclear Information System (INIS)

    Ekbom, L.B.; Hannerz, K.; Henrikson, K.S.

    1980-01-01

    The Nuclear Fuel Safety Project (KBS) has proposed that spent non-processed nuclear fuel shall be disposed of by enclosing it in copper canisters or alternatively that reprocessed and vitrified waste shall be enclosed in a titanium canister with a lead lining. The canisters are to be placed in vertical drill-holes in rock, 500 m below ground and embedded in a buffer of sand and bentonite. The purpose of this arrangement is to raise several obstacles against fission products reaching the biosphere. The thick-walled canister is one of these obstacles, which is proposed to be a barrier for a considerable period of time. Corrosion is the limiting factor of the canister durability. The rate of corrosion is dependent on the amount and transport of corrosion reactants to the surface of the canister. The thermodynamic possibilities for various corrosion reactions on copper and lead under the prevailing conditions were studied, also with regard to bacterial influence. Entrapped atmospheric oxygen and sulphide in the ground water were found to be reactants of importance. The supply of oxygen and sulphide by diffusion was calculated, and hence the greatest possible corrosion. The corrosion attack may start as pitting but will penetrate into the thick metal wall at a decreasing rate. An expert group arrived at the conclusion that under given conditions the canisters will last for a very long time (hundreds of thousands of years for copper canisters). In order to verify the expected high corrosion resistance of titanium, laboratory tests have been carried out in environments, which must be considered to provide accelerated rather than simulated tests

  9. Parametric analyses of summative scores may lead to conflicting inferences when comparing groups: A simulation study.

    Science.gov (United States)

    Khan, Asaduzzaman; Chien, Chi-Wen; Bagraith, Karl S

    2015-04-01

    To investigate whether using a parametric statistic in comparing groups leads to different conclusions when using summative scores from rating scales compared with using their corresponding Rasch-based measures. A Monte Carlo simulation study was designed to examine between-group differences in the change scores derived from summative scores from rating scales, and those derived from their corresponding Rasch-based measures, using 1-way analysis of variance. The degree of inconsistency between the 2 scoring approaches (i.e. summative and Rasch-based) was examined, using varying sample sizes, scale difficulties and person ability conditions. This simulation study revealed scaling artefacts that could arise from using summative scores rather than Rasch-based measures for determining the changes between groups. The group differences in the change scores were statistically significant for summative scores under all test conditions and sample size scenarios. However, none of the group differences in the change scores were significant when using the corresponding Rasch-based measures. This study raises questions about the validity of the inference on group differences of summative score changes in parametric analyses. Moreover, it provides a rationale for the use of Rasch-based measures, which can allow valid parametric analyses of rating scale data.

  10. Nuclear PDF studies with proton-lead measurements with the ALICE detector

    CERN Document Server

    Mischke, André

    2017-01-01

    The proton-lead programme at CERN’s Large Hadron Collider allowed the study of cold-nuclear matter effects from the initial state, such as Cronin enhancement, nuclear shadowing and gluon saturation. They result in a modification of the production cross section and thus provide crucial tests of predictions from perturbative Quantum-Chromodynamics. Furthermore, these control measurements are needed to characterise the extent to which initial-state effects can be differentiated from effects due to final-state interactions in the so-called quark-gluon plasma, produced in high-energy collisions of heavy atomic nuclei. In this contribution, recent results from the ALICE experiment on the measurements of lightflavour production and jets will be presented. Especially, the multi-strange baryon yields allow the study of the canonical suppression in small systems, whereas jets have been studied in term of the acoplanarity between full and charged jets and the nuclear modification factor as a function of collision cent...

  11. Zinc and lead transfer in a contaminated roadside soil: Experimental study and modeling

    International Nuclear Information System (INIS)

    Hanna, K.; Lassabatere, L.; Bechet, B.

    2009-01-01

    The application of a surface complexation model to simulate the sorption of metals on single sorbents is very well investigated, but very little is known regarding the use of surface complexation modeling to simulate the metal mobility in contaminated roadside soils. The overall objective of this study was to examine whether the use of the surface complexation model (SCM) could correctly describe the migration of zinc and lead in roadside soil under various physicochemical conditions. The release and transport of Zn and Pb was studied by means of batch reactors and saturated chromatography columns. Soil batch experiments were conducted to evaluate the effects of pH variation and ionic strength on the metal mobility from soil. Elution of Pb and Zn was examined in column experiments by using acetic acid at pH5 and EDTA at pH7. The modeling work has focused on the development of a SCM using MINTEQ2 database incorporated in PHREEQC-2 to describe the interactions between trace metals and the main mineral soil components (quartz, iron and aluminum oxides). In this study, it was found that the SCM was able to simulate the mobility of metals from soil by assuming one mononuclear surface reaction between one solution species (Me 2+ ) and one type of site on the surface of soil dominant sorbents

  12. Hazardous chemicals in synthetic turf materials and their bioaccessibility in digestive fluids.

    Science.gov (United States)

    Zhang, Junfeng Jim; Han, In-Kyu; Zhang, Lin; Crain, William

    2008-11-01

    Many synthetic turf fields consist of not only artificial grass but also rubber granules that are used as infill. The public concerns about toxic chemicals possibly contained in either artificial (polyethylene) grass fibers or rubber granules have been escalating but are based on very limited information available to date. The aim of this research was to obtain data that will help assess potential health risks associated with chemical exposure. In this small-scale study, we collected seven samples of rubber granules and one sample of artificial grass fiber from synthetic turf fields at different ages of the fields. We analyzed these samples to determine the contents (maximum concentrations) of polycyclic aromatic hydrocarbons (PAHs) and several metals (Zn, Cr, As, Cd, and Pb). We also analyzed these samples to determine their bioaccessible fractions of PAHs and metals in synthetic digestive fluids including saliva, gastric fluid, and intestinal fluid through a laboratory simulation technique. Our findings include: (1) rubber granules often, especially when the synthetic turf fields were newer, contained PAHs at levels above health-based soil standards. The levels of PAHs generally appear to decline as the field ages. However, the decay trend may be complicated by adding new rubber granules to compensate for the loss of the material. (2) PAHs contained in rubber granules had zero or near-zero bioaccessibility in the synthetic digestive fluids. (3) The zinc contents were found to far exceed the soil limit. (4) Except one sample with a moderate lead content of 53 p.p.m., the other samples had relatively low concentrations of lead (3.12-5.76 p.p.m.), according to soil standards. However, 24.7-44.2% of the lead in the rubber granules was bioaccessible in the synthetic gastric fluid. (5) The artificial grass fiber sample showed a chromium content of 3.93 p.p.m., and 34.6% and 54.0% bioaccessibility of lead in the synthetic gastric and intestinal fluids, respectively.

  13. A high-speed study of the dynamic bullet-body interactions produced by grazing gunshots with full metal jacketed and lead projectiles.

    Science.gov (United States)

    Thali, M J; Kneubuehl, B P; Zollinger, U; Dirnhofer, R

    2003-03-27

    Experimenting upon a synthetic, non-biological Skull-Brain Model, our goal was to document and study the bullet-body interaction of grazing (glancing, tangential) gunshots. Thanks to the high-speed study of the dynamic bullet-body interaction it was possible to document the glancing behavior of projectiles with a resolution of 50 million pictures per second. It was possible to demonstrate the differing deformation and fragmentation patterns between the 9mm Luger full metal jacketed projectile and the 38 Smith & Wesson (S & W) lead round nose projectile. In a true-to-life manner the morphologic fracture systems could be documented by utilization of the model in dependence of the projectile's behavior, deformation, and fragmentation. Based on these experimental studies with body models, conclusions could be drawn for surgical and reconstructive forensic questions in real cases. In summary, model substitutes offer a suitable basis for the study of the bullet-body interaction because the experiments are reproducible, totally independent of the biological variances of corpse and animal experiments, and are harmless from the ethical perspective.

  14. Synthetic food coloring and behavior: a dose response effect in a double-blind, placebo-controlled, repeated-measures study.

    Science.gov (United States)

    Rowe, K S; Rowe, K J

    1994-11-01

    To establish whether there is an association between the ingestion of synthetic food colorings and behavioral change in children referred for assessment of "hyperactivity." From approximately 800 children referred to the Royal Children's Hospital (Melbourne) for assessment of suspected hyperactivity, 200 were included in a 6-week open trial of a diet free of synthetic food coloring. The parents of 150 children reported behavioral improvement with the diet, and deterioration on the introduction of foods noted to contain synthetic coloring. A 30-item behavioral rating inventory was devised from an examination of the clinical histories of 50 suspected reactors. Thirty-four other children (23 suspected reactors, 11 uncertain reactors) and 20 control subjects, aged 2 to 14 years, were studied. A 21-day, double-blind, placebo-controlled, repeated-measures study used each child as his or her own control. Placebo, or one of six dose levels of tartrazine (1, 2, 5, 10, 20, 50 mg), was administered randomly each morning, and behavioral ratings were recorded by parents at the end of each 24 hours. The study identified 24 children as clear reactors (19 of 23 "suspected reactors," 3 of 11 "uncertain reactors," and 2 of 20 "control subjects"). They were irritable and restless and had sleep disturbance. Significant reactions were observed at all six dose levels. A dose response effect was obtained. With a dose increase greater than 10 mg, the duration of effect was prolonged. Behavioral changes in irritability, restlessness, and sleep disturbance are associated with the ingestion of tartrazine in some children. A dose response effect was observed.

  15. Technical performance of percutaneous leads for spinal cord stimulation: a modeling study

    NARCIS (Netherlands)

    Manola, L.; Holsheimer, J.; Veltink, Petrus H.

    Objective. To compare the technical performance of different percutaneous lead types for spinal cord stimulation. Methods. Using the UT-SCS software (University of Twente's spinal cord stimulation), lead models having similar characteristics such as the 3487A PISCES-Quad (PQ), 3887 PISCES-Quad

  16. Longitudinal changes in bone lead levels: the VA Normative Aging Study

    Science.gov (United States)

    Wilker, Elissa; Korrick, Susan; Nie, Linda H; Sparrow, David; Vokonas, Pantel; Coull, Brent; Wright, Robert O.; Schwartz, Joel; Hu, Howard

    2011-01-01

    Objective Bone lead is a cumulative measure of lead exposure that can also be remobilized. We examined repeated measures of bone lead over 11 years to characterize long-term changes and identify predictors of tibia and patella lead stores in an elderly male population. Methods Lead was measured every 3–5 years by k-x-ray fluorescence and mixed-effect models with random effects were used to evaluate change over time. Results 554 participants provided up to 4 bone lead measurements. Final models predicted a −1.4% annual decline (95%CI: −2.2,−0.7) for tibia lead and piecewise linear model for patella with an initial decline of 5.1% per year (95%CI: −6.2,−3.9) during the first 4.6 years but no significant change thereafter (−0.4% (95% CI: −2.4, 1.7)). Conclusions These results suggest that bone lead half-life may be longer than previously reported. PMID:21788910

  17. Lead user innovation and entrepreneurship in the virtual world: A study of Second Life residents

    NARCIS (Netherlands)

    Chandra, Y.

    2009-01-01

    While prior research have investigated factors, processes and pathways traversed in lead user innovation within the three-dimensional concept of space and time, there is a scant attention on lead user innovation and ‘user entrepreneurship’ that take place within the four-dimensional concept of space

  18. Application of diffraction techniques in studies of lead/acid battery performance

    International Nuclear Information System (INIS)

    Hill, R.J.

    1984-01-01

    The author presents a resume of the most significant contributions to lead/acid battery research made by X-ray, neutron, and electron diffraction techniques. In addition, those areas of research are defined which show the most promise in achieving improvements in the performance of the lead/acid battery. (Auth.)

  19. Metal immobilization in soils using synthetic zeolites

    NARCIS (Netherlands)

    Osté, L.A.; Lexmond, T.M.; Riemsdijk, van W.H.

    2002-01-01

    In situ immobilization of heavy metals in contaminated soils is a technique to improve soil quality. Synthetic zeolites are potentially useful additives to bind heavy metals. This study selected the most effective zeolite in cadmium and zinc binding out of six synthetic zeolites (mordenite-type,

  20. Blood lead level studies by the Public Health Service in an industrial stress area

    Energy Technology Data Exchange (ETDEWEB)

    Jantzen, G.

    1981-12-01

    The general directions of the European Community concerning lead resulted to be useful for analysing the biologic impact on the population living in an industrial immission area and for differentiating within this locality affected and non-affected residential districts. Consequently the social-hygienic and regional-hygienic measures are limited and justified territorially. The environmental parameters, their relation to the distance at which an industrial plant is situated and the blood lead values are indicated. Recommendations are given, which concern the protection of health and even the reconstruction of the residential area by immission-reducing measures. It was found that the lead impact on children is higher than that on grown-ups. Tables illustrate the symptomatology of lead impacts, its relation to blood lead concentration, the degree of impact measured in children and grown-ups and the corresponding necessary measures as auxiliary methods for the Public Health Service and the physicians.

  1. Physical and spectroscopic studies on manganese ions in lead halo borate glasses

    Science.gov (United States)

    Sekhar, K. Chandra; Hameed, Abdul; Ramadevudu, G.; Chary, M. Narasimha; Shareefuddin, Md.

    2017-06-01

    Lead halo borate glass systems containing manganese ions have been investigated to study the role of halide ions on the physical, optical and EPR studies. The amorphous phase of the prepared glass samples xPbX2-(30 - x)PbO-69.5B2O3-0.5MnO2 with X = F, Cl and Br and 5 ≤ x ≤ 25 mol% was confirmed from their X-ray diffraction spectra. Ionic radii of the halides played an important role in the physical properties. From the optical absorption spectra, optical band gap and Urbach energy values were evaluated. The EPR spectra have shown a six-line hyperfine (HF) structure centered at g ≈ 2.0 and attributed to Mn2+ centers in octahedral symmetry. The other signals at g ≈ 3.3 and 4.3 were attributed to the rhombic surroundings of Mn2+ ions. The negative shift in g-value revealed highly ionic environment around the Mn2+ ion in the glass hosts. The HF splitting constant (A), number of spins (N) and susceptibility (χ) values of the prepared glasses were also reported.

  2. Bulk and interface recombination in planar lead halide perovskite solar cells: A Drift-Diffusion study

    Science.gov (United States)

    Olyaeefar, Babak; Ahmadi-Kandjani, Sohrab; Asgari, Asghar

    2017-10-01

    A theoretical approach based on Drift-Diffusion equations is presented to study planar mixed lead halide perovskite solar cells. Updated physical parameters such as permittivity, mobility, effective density of states and doping density is employed in simulations. Current-voltage curve data for two experimental sample is imported and through fitting with the model, density of bulk and interface defects is calculated. We obtain the bulk defect density around 1016 cm-3 and surface recombination velocities in the range of 10 cm/s. These values which are in good agreement with experimental measurements and considerably deviated from previous theoretical studies, verify the model and adopted constants. Shockley-Queisser limit is also presented as the ideal device and the effect of bulk and interface defects are presented as loss factors that cause departure from this limit. Our simulations conclude that the overall efficiency of perovskite solar cells is mainly governed by the open-circuit voltage and also identify the interface defects as the major loss factor in these devices.

  3. KINETIC AND EQUILIBRIUM STUDIES OF LEAD AND CADMIUM BIOSORPTION FROM AQUEOUS SOLUTIONS BY SARGASSUM SPP. BIOMASS

    Directory of Open Access Journals (Sweden)

    R. Nabizadeh, K. Naddafi, R. Saeedi, A. H. Mahvi, F. Vaezi, K. Yaghmaeian and S. Nazmara

    2005-07-01

    Full Text Available Contamination of the aqueous environment by heavy metals is a worldwide environmental problem. Biosorption of lead (II and cadmium (II from aqueous solutions by brown algae Sargassum spp.biomass was studied in a batch system. The heavy metals uptake was found to be rapid and reached to 88-96% of equilibrium capacity of biosorption in 15min. The pseudo second-order and saturation rate equations were found in the best fitness with the kinetic data (R2 > 0.99. The data obtained from experiments of single-component biosorption isotherm were analyzed using the Freundlich, Langmuir, Freundlich-Langmuir and Redlich-Peterson isotherm models. The Redlich-Peterson equation described the biosorption isotherm of Pb2+ and Cd2+ with high correlation coefficient (R2 > 0.99 and better than the other equations. The effect of Na+, K+, Mg2+ and Ca2+ on the biosorption of Pb2+ was not significant, but the metal ions affected the biosorption of Cd2+ considerably. According to the Langmuir model, the maximum uptake capacities (qm of Sargassum spp. for Pb2+ and Cd2+ were obtained as 1.70 and 1.02mmol/g, respectively. Although the Sargassum spp. used in this study can be classified as an efficient biosorbent.

  4. Does cannabis use lead to depression and suicidal behaviours? A population-based longitudinal study.

    Science.gov (United States)

    Pedersen, W

    2008-11-01

    This study investigates the relationship between cannabis use and later depression, suicidal ideation and suicide attempts in a cohort of young Norwegians. Data were gathered through the Young in Norway longitudinal study, in which a population-based sample of 2033 Norwegians were followed up over a 13-year period, from their early teens to their late twenties. Data were gathered on: (a) exposure to cannabis use; and (b) depression, suicide ideation and suicide attempts. In addition, information about possible confounding factors was included. In early adolescence, no associations with later depression or suicidal behaviours were observed. In the sample's twenties, we observed highly significant associations with suicide ideation and suicide attempts. When adjusting for confounders, the OR was 2.9 (95% CI 1.3-6.1) for later suicide attempts in the group who had used cannabis 11+ times during the past 12 months. The findings suggest that exposure to cannabis by itself does not lead to depression but that it may be associated with later suicidal thoughts and attempts.

  5. Synthetic Developments of Nontoxic Quantum Dots.

    Science.gov (United States)

    Das, Adita; Snee, Preston T

    2016-03-03

    Semiconductor nanocrystals, or quantum dots (QDs), are candidates for biological sensing, photovoltaics, and catalysis due to their unique photophysical properties. The most studied QDs are composed of heavy metals like cadmium and lead. However, this engenders concerns over heavy metal toxicity. To address this issue, numerous studies have explored the development of nontoxic (or more accurately less toxic) quantum dots. In this Review, we select three major classes of nontoxic quantum dots composed of carbon, silicon and Group I-III-VI elements and discuss the myriad of synthetic strategies and surface modification methods to synthesize quantum dots composed of these material systems. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Study of samarium modified lead zirconate titanate and nickel zinc ferrite composite system

    Energy Technology Data Exchange (ETDEWEB)

    Rani, Rekha [Department of Physics, SD PG College, Panipat 132103 (India); School of Physics and Materials Science, Thapar University, Patiala 147004 (India); Juneja, J.K., E-mail: jk_juneja@yahoo.com [Department of Physics, Hindu College, Sonepat 131001 (India); Singh, Sangeeta [Department of Physics, GVM Girls College, Sonepat 131001 (India); Raina, K.K. [School of Physics and Materials Science, Thapar University, Patiala 147004 (India); Prakash, Chandra [Solid State Physics Laboratory, Timarpur, Delhi 110054 (India)

    2015-03-15

    In the present work, composites of samarium substituted lead zirconate titanate and nickel zinc ferrite with compositional formula 0.95Pb{sub 1−3x/2} Sm{sub x}Zr{sub 0.65}Ti{sub 0.35}O{sub 3}–0.05Ni{sub 0.8}Zn{sub 0.2}Fe{sub 2}O{sub 4} (x=0, 0.01, 0.02 and 0.03) were prepared by the conventional solid state route. X-ray diffraction analysis was carried out to confirm the coexistence of individual phases. Microstructural study was done by using scanning electron microscope. Dielectric constant and loss were studied as a function of temperature and frequency. To study ferroelectric and magnetic properties of the composite samples, corresponding P–E and M–H hysteresis loops were recorded. Change in magnetic properties of electrically poled composite sample (x=0.02) was studied to confirm the magnetoelectric (ME) coupling. ME coefficient (dE/dH) of the samples (x=0 and 0.02) was measured as a function of DC magnetic field. - Highlights: • We are reporting the effect of Sm substitution on PZT–NiZn ferrite composites. • Observation of both P–E and M–H loops confirms ferroelectric and magnetic ordering. • With Sm substitution, significant improvement in properties was observed. • Increase in magnetization for electrically poled sample is evidence of ME coupling. • Electric polarization is generated by applying magnetic field.

  7. A Comprehensive Study on Fast Dispersible and Slow-Releasing Characteristic of Orange Peel Pectin in Relation to Established Synthetic Polymer.

    Science.gov (United States)

    Srivastava, Pranati; Singh, Mahendra; Bhargava, Shilpi

    2017-10-01

    In the present work, the method to extract, isolate, and characterize orange peel pectin using soxhlation, and thereafter, the use of this polymer-polymer in the formulation of fast dispersable and slow-releasing tablet has been studied. Thereafter, the evaluation and comparison of fast dispersible/slow-releasing tablets using orange peel pectin versus prepared using sodium starch glycolate (SSG) were carried out. In the present investigation, extraction methodology was employed for isolation of pectin from orange peels. Four different batches with each polymer were prepared with varying concentration of superdisintegrant and bulking agent using diclofenac sodium as model drug. Diclofenac sodium stands as easily available, cheap, and good candidate to demonstrate disintegrant property. The formulation involved wet granulation method for the preparation of tablets of each batch. The tablets were evaluated for hardness, friability, thickness, wetting time, deaggregation time, and in vitro release characteristic data. It was observed that parameters for batch O2* were comparable with that of synthetic superdisintegrant. This batch gave around 92.12% drug release in period of 90 min. The study showed that orange peel pectin could be a potential candidate for formulation of orodispersible dosage forms in competence to SSG, which is established superdisintegrant. The results led to the conclusion that the use of natural polymers in formulation of pharmaceutical dosage form can be put into practice on industrial scale meeting the similar requirements as done by synthetic polymers. The present work aims to demonstrate and establish the use of naturally derived polymer, i.e., orange peel pectin as a superdisintegrant. The extraction methodology has been discussed followed by comparative analysis with a synthetic polymer. Abbreviations used: O1-O2: Batches Containing Orange peel pectin, S1-S2: Batches containing SSG, SSG: Sodium starch glycolate, NDDS: Novel drug delivery

  8. [STUDY OF HUMORAL IMMUNE RESPONSE FEATURES BASED ON MODELLING OF ANTIGEN DETERMINANTS OF HEPATITIS C VIRUS BY SYNTHETIC PEPTIDES AND GENETICALLY ENGINEERED POLYPEPTIDES].

    Science.gov (United States)

    Kruglov, I V

    2015-01-01

    Study of humoral immune response features in patients with acute hepatitis C (AHC) with various disease outcomes based on modelling of antigen determinants of hepatitis C virus (HCV) by synthetic peptides and genetically engineered polypeptides. 20 patients with icteric form of AHC based on clinical-biochemical presentation and HCV RNA detection by PCR in blood sera during 12 months from the disease onset were included into the study. Antibody seroconversion study was carried out by EIA. Genetically engineered proteins and synthetic peptides were used as antigens. Similarity and differences of humoral immune response against the HCV antigens used in this study depending on the disease outcome (convalescence or chronicity) were shown. Significant difference of the humoral immune response to both HCV core protein and various fragments of the immune dominant region of this protein were detected, that indicates on a link of these features of immune response with perspectives of a more or less favorable disease development. The regularities of seroconversion detected allow to consider anti-NS5 IgG as a prognostic marker of the disease chronicity. Such marker, as anti-NS3 IgG, is important for diagnostics, but not for disease outcome prognosis.

  9. Experimental study of gas-cooled current leads for superconducting magnets

    International Nuclear Information System (INIS)

    Warren, R.P.

    1978-04-01

    Design details and experimental test results from several design variations of the gas-cooled, copper current leads used in conjunction with the superconducting dipole magnets for ESCAR (Experimental Superconducting Accelerator Ring) are reported. Thermal acoustic oscillations, which were experienced with an initial design, were eliminated in subsequent designs by a reduction of the hydraulic diameter. The occurrence of these oscillations is in general agreement with the stability analysis of Rott but the observed gas flow dependence is not in agreement with some other recently reported results for leads operated supercritical phase coolant. An empirically determined correlation was obtained by plotting lead resistance vs. enthalpy gain of the coolant gas. The resulting family of curves can be reduced to a single line on a plot of effective resistivity vs. the product of current and cross-sectional area divided by the product of the square of the mass flow of the coolant and the lead length. This correlation, which should be applicable to other designs of copper current leads in which ideal heat transfer to the coolant gas is approached, predicts that the enthalpy gain of the coolant, and therefore the peak lead temperature, is proportional to the cube of the ratio of current to coolant mass flow. The effective value of the strongly temperature-dependent kinematic viscosity of the coolant gas was found to vary linearly with the effective resistivity of the lead

  10. Lead (Pb) Isotope Baselines for Studies of Ancient Human Migration and Trade in the Maya Region.

    Science.gov (United States)

    Sharpe, Ashley E; Kamenov, George D; Gilli, Adrian; Hodell, David A; Emery, Kitty F; Brenner, Mark; Krigbaum, John

    2016-01-01

    We examined the potential use of lead (Pb) isotopes to source archaeological materials from the Maya region of Mesoamerica. The main objectives were to determine if: 1) geologic terrains throughout the Maya area exhibit distinct lead isotope ratios (206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb), and 2) a combination of lead and strontium ratios can enhance sourcing procedures in the Mesoamerica region. We analyzed 60 rock samples for lead isotope ratios and a representative subset of samples for lead, uranium, and thorium concentrations across the Maya region, including the Northern Lowlands of the Mexican Yucatan Peninsula, the Southern Lowlands of Guatemala and Belize, the Volcanic Highlands, the Belizean Maya Mountains, and the Metamorphic Province/Motagua Valley. Although there is some overlap within certain sub-regions, particularly the geologically diverse Metamorphic Province, lead isotopes can be used to distinguish between the Northern Lowlands, the Southern Lowlands, and the Volcanic Highlands. The distinct lead isotope ratios in the sub-regions are related to the geology of the Maya area, exhibiting a general trend in the lowlands of geologically younger rocks in the north to older rocks in the south, and Cenozoic volcanic rocks in the southern highlands. Combined with other sourcing techniques such as strontium (87Sr/86Sr) and oxygen (δ18O), a regional baseline for lead isotope ratios can contribute to the development of lead isoscapes in the Maya area, and may help to distinguish among geographic sub-regions at a finer scale than has been previously possible. These isotope baselines will provide archaeologists with an additional tool to track the origin and movement of ancient humans and artifacts across this important region.

  11. Lead (Pb Isotope Baselines for Studies of Ancient Human Migration and Trade in the Maya Region.

    Directory of Open Access Journals (Sweden)

    Ashley E Sharpe

    Full Text Available We examined the potential use of lead (Pb isotopes to source archaeological materials from the Maya region of Mesoamerica. The main objectives were to determine if: 1 geologic terrains throughout the Maya area exhibit distinct lead isotope ratios (206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb, and 2 a combination of lead and strontium ratios can enhance sourcing procedures in the Mesoamerica region. We analyzed 60 rock samples for lead isotope ratios and a representative subset of samples for lead, uranium, and thorium concentrations across the Maya region, including the Northern Lowlands of the Mexican Yucatan Peninsula, the Southern Lowlands of Guatemala and Belize, the Volcanic Highlands, the Belizean Maya Mountains, and the Metamorphic Province/Motagua Valley. Although there is some overlap within certain sub-regions, particularly the geologically diverse Metamorphic Province, lead isotopes can be used to distinguish between the Northern Lowlands, the Southern Lowlands, and the Volcanic Highlands. The distinct lead isotope ratios in the sub-regions are related to the geology of the Maya area, exhibiting a general trend in the lowlands of geologically younger rocks in the north to older rocks in the south, and Cenozoic volcanic rocks in the southern highlands. Combined with other sourcing techniques such as strontium (87Sr/86Sr and oxygen (δ18O, a regional baseline for lead isotope ratios can contribute to the development of lead isoscapes in the Maya area, and may help to distinguish among geographic sub-regions at a finer scale than has been previously possible. These isotope baselines will provide archaeologists with an additional tool to track the origin and movement of ancient humans and artifacts across this important region.

  12. Lead (Pb) Isotope Baselines for Studies of Ancient Human Migration and Trade in the Maya Region

    Science.gov (United States)

    Kamenov, George D.; Gilli, Adrian; Hodell, David A.; Emery, Kitty F.; Brenner, Mark; Krigbaum, John

    2016-01-01

    We examined the potential use of lead (Pb) isotopes to source archaeological materials from the Maya region of Mesoamerica. The main objectives were to determine if: 1) geologic terrains throughout the Maya area exhibit distinct lead isotope ratios (206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb), and 2) a combination of lead and strontium ratios can enhance sourcing procedures in the Mesoamerica region. We analyzed 60 rock samples for lead isotope ratios and a representative subset of samples for lead, uranium, and thorium concentrations across the Maya region, including the Northern Lowlands of the Mexican Yucatan Peninsula, the Southern Lowlands of Guatemala and Belize, the Volcanic Highlands, the Belizean Maya Mountains, and the Metamorphic Province/Motagua Valley. Although there is some overlap within certain sub-regions, particularly the geologically diverse Metamorphic Province, lead isotopes can be used to distinguish between the Northern Lowlands, the Southern Lowlands, and the Volcanic Highlands. The distinct lead isotope ratios in the sub-regions are related to the geology of the Maya area, exhibiting a general trend in the lowlands of geologically younger rocks in the north to older rocks in the south, and Cenozoic volcanic rocks in the southern highlands. Combined with other sourcing techniques such as strontium (87Sr/86Sr) and oxygen (δ18O), a regional baseline for lead isotope ratios can contribute to the development of lead isoscapes in the Maya area, and may help to distinguish among geographic sub-regions at a finer scale than has been previously possible. These isotope baselines will provide archaeologists with an additional tool to track the origin and movement of ancient humans and artifacts across this important region. PMID:27806065

  13. COST531 project: Study of the advanced materials for lead free soldering

    Directory of Open Access Journals (Sweden)

    Kroupa A.

    2007-01-01

    Full Text Available The COST 531 [1] project runt in the years 2002-2007, and dealt with the materials suitable for lead-free soldering. The main aim was to increase the basic knowledge on possible alloy systems that were used or planned to be used as lead-free solder materials and offer scientific information about these materials in order to replace the currently used lead-containing solders. The databases of materials and thermodynamic properties are one of the expected results and the basic features and properties of the thermodynamic database, allowing to model phase diagrams in multicomponent systems, are described in following paper.

  14. Lead Poisoning

    Science.gov (United States)

    Lead is a metal that occurs naturally in the earth's crust. Lead can be found in all parts of our ... from human activities such as mining and manufacturing. Lead used to be in paint; older houses may ...

  15. 75 FR 76336 - Notice of Data Availability Regarding Two Studies of Ambient Lead Concentrations Near a General...

    Science.gov (United States)

    2010-12-08

    ... studies are located in Docket ID No. EPA-HQ-OAR-2006-0735. II. How does this information relate to the.... Modeling results show aircraft engine run-up is the most important source contribution to the maximum lead concentration. Sensitivity analysis shows that engine run-up time, lead concentration in aviation gasoline, and...

  16. Case Studies of Leading Edge Small Urban High Schools. Relevance Strategic Designs: 5. Life Academy of Health and Bioscience

    Science.gov (United States)

    Shields, Regis Anne; Ireland, Nicole; City, Elizabeth; Derderian, Julie; Miles, Karen Hawley

    2008-01-01

    This report is one of nine detailed case studies of small urban high schools that served as the foundation for the Education Resource Strategies (ERS) report "Strategic Designs: Lessons from Leading Edge Small Urban High Schools." These nine schools were dubbed "Leading Edge Schools" because they stand apart from other high…

  17. Case Studies of Leading Edge Small Urban High Schools. Relevance Strategic Designs: 8. High Tech High School

    Science.gov (United States)

    Shields, Regis Anne; Ireland, Nicole; City, Elizabeth; Derderian, Julie; Miles, Karen Hawley

    2008-01-01

    This report is one of nine detailed case studies of small urban high schools that served as the foundation for the Education Resource Strategies (ERS) report "Strategic Designs: Lessons from Leading Edge Small Urban High Schools." These nine schools were dubbed "Leading Edge Schools" because they stand apart from other high…

  18. Case Studies of Leading Edge Small Urban High Schools. Personalization Strategic Designs: 9. MetWest High School

    Science.gov (United States)

    Shields, Regis Anne; Ireland, Nicole; City, Elizabeth; Derderian, Julie; Miles, Karen Hawley

    2008-01-01

    This report is one of nine detailed case studies of small urban high schools that served as the foundation for the Education Resource Strategies (ERS) report "Strategic Designs: Lessons from Leading Edge Small Urban High Schools." These nine schools were dubbed "Leading Edge Schools" because they stand apart from other high…

  19. Case Studies of Leading Edge Small Urban High Schools. Relevance Strategic Designs: 7. TechBoston Academy

    Science.gov (United States)

    Shields, Regis Anne; Ireland, Nicole; City, Elizabeth; Derderian, Julie; Miles, Karen Hawley

    2008-01-01

    This report is one of nine detailed case studies of small urban high schools that served as the foundation for the Education Resource Strategies (ERS) report "Strategic Designs: Lessons from Leading Edge Small Urban High Schools." These nine schools were dubbed "Leading Edge Schools" because they stand apart from other high…

  20. Case Studies of Leading Edge Small Urban High Schools. Core Academic Strategic Designs: 3. University Park Campus School

    Science.gov (United States)

    Shields, Regis Anne; Ireland, Nicole; City, Elizabeth; Derderian, Julie; Miles, Karen Hawley

    2008-01-01

    This report is one of nine detailed case studies of small urban high schools that served as the foundation for the Education Resource Strategies (ERS) report "Strategic Designs: Lessons from Leading Edge Small Urban High Schools." These nine schools were dubbed "Leading Edge Schools" because they stand apart from other high…

  1. Case Studies of Leading Edge Small Urban High Schools. Core Academic Strategic Designs: 1. Academy of the Pacific Rim

    Science.gov (United States)

    Shields, Regis Anne; Ireland, Nicole; City, Elizabeth; Derderian, Julie; Miles, Karen Hawley

    2008-01-01

    This report is one of nine detailed case studies of small urban high schools that served as the foundation for the Education Resource Strategies (ERS) report "Strategic Designs: Lessons from Leading Edge Small Urban High Schools." These nine schools were dubbed "Leading Edge Schools" because they stand apart from other high…

  2. Case Studies of Leading Edge Small Urban High Schools. Core Academic Strategic Designs: 2. Noble Street Charter High School

    Science.gov (United States)

    Shields, Regis Anne; Ireland, Nicole; City, Elizabeth; Derderian, Julie; Miles, Karen Hawley

    2008-01-01

    This report is one of nine detailed case studies of small urban high schools that served as the foundation for the Education Resource Strategies (ERS) report "Strategic Designs: Lessons from Leading Edge Small Urban High Schools." These nine schools were dubbed "Leading Edge Schools" because they stand apart from other high…

  3. Synthetic biological networks

    International Nuclear Information System (INIS)

    Archer, Eric; Süel, Gürol M

    2013-01-01

    Despite their obvious relationship and overlap, the field of physics is blessed with many insightful laws, while such laws are sadly absent in biology. Here we aim to discuss how the rise of a more recent field known as synthetic biology may allow us to more directly test hypotheses regarding the possible design principles of natural biological networks and systems. In particular, this review focuses on synthetic gene regulatory networks engineered to perform specific functions or exhibit particular dynamic behaviors. Advances in synthetic biology may set the stage to uncover the relationship of potential biological principles to those developed in physics. (review article)

  4. Synthetic Base Fluids

    Science.gov (United States)

    Brown, M.; Fotheringham, J. D.; Hoyes, T. J.; Mortier, R. M.; Orszulik, S. T.; Randles, S. J.; Stroud, P. M.

    The chemical nature and technology of the main synthetic lubricant base fluids is described, covering polyalphaolefins, alkylated aromatics, gas-to-liquid (GTL) base fluids, polybutenes, aliphatic diesters, polyolesters, polyalkylene glycols or PAGs and phosphate esters.Other synthetic lubricant base oils such as the silicones, borate esters, perfluoroethers and polyphenylene ethers are considered to have restricted applications due to either high cost or performance limitations and are not considered here.Each of the main synthetic base fluids is described for their chemical and physical properties, manufacture and production, their chemistry, key properties, applications and their implications when used in the environment.

  5. A numerical and experimental study of the effects of dynamic roughness on laminar leading edge separation

    Science.gov (United States)

    Gall, Peter D.

    The aircraft industry, as a whole, has been deeply concerned with improving the aerodynamic efficiency of current and future flight vehicles, particularly in the commercial and military markets. However, of particular interest to the field of aerodynamics is the elusive concept of a workable flow control mechanism. Effective flow control is a concept which if properly applied can increase aerodynamic efficiency. Various concepts and ideas to obtain successful flow control have been studied in an attempt to reap these rewards. Some examples include boundary layer blowing (steady and periodic), suction, and compliant walls for laminar flow control. The overall goal of flow control is to increase performance by increasing lift, reducing drag, and delaying or eliminating leading edge separation. The specific objectives of flow control are to (1) delay or eliminate flow separation, (2) delay boundary layer transition, and (3) and reduce skin friction drag. The purpose of this research is to investigate dynamic roughness as a novel method of flow control technology for external boundary layer flows. As opposed to standard surface roughness, dynamic roughness incorporates small time dependent perturbations to the surface of the airfoil. These surface perturbations are actual humps and/or ridges on the surface of the airfoil that are on the scale of the laminar boundary, and oscillate with an unsteady motion. Research has shown that this can provide a means to modify the instantaneous and mean velocity profile near the wall and favorably control the existing state of the boundary layer. Several flow control parameters were studied including dynamic roughness frequency, amplitude, and geometry. The results of this study have shown, both numerically and experimentally, that dynamic roughness can provide an effective means for eliminating both a short and long laminar separation bubble and possibly prove a viable alternative in effective flow control, hence reaping some of

  6. Study and understanding of the ageing mechanisms in lead-calcium alloys

    International Nuclear Information System (INIS)

    Rossi, F.

    2006-12-01

    The data available in the literature about ageing and over-ageing of lead-calcium alloys are often incomplete and inconsistent. It is undoubtedly due to the experimental difficulties encountered to observe the structure transformations which are numerous. As a result there is a certain confusion among the results of the different authors. Moreover, small variations in the process parameters and chemical composition may have some influence on the alloy behaviour. This work enabled us to obtain a set of TTT diagrams, more realistic and accurate than the ones available in the literature. Experimental techniques developed (particularly the preservation of the cold chain with is essential for the guaranty of the results repeatability), enabled particularly the study of the first transformations and better control the five stages of ageing and over-ageing. Our work have enabled to determine precisely the kinetics and the mechanisms of the transformations. This work constitutes a thorough analysis of the ageing and over-ageing of theses alloys. (author)

  7. Identification and systematical studies of the electron-capture delayed fission (ECDF) in the lead region

    CERN Multimedia

    Pauwels, D B; Lane, J

    2008-01-01

    In our recent experiment (March 2007) at the velocity filter SHIP(GSI) we observed the electron-capture delayed fission of the odd-odd isotope $^{194}$At. This is the first unambiguous identification of this phenomenon in the very neutron-deficient nuclei in the vicinity of the proton shell closure at Z=82. In addition, the total kinetic energy (TKE) for the daughter nuclide $^{194}$Po was measured, despite the fact that this isotope does not decay via spontaneous fission. Semi-empirical analysis of the electron-capture Q$_{EC}$ values and fission barriers B$_{f}$ shows that a relatively broad island of ECDF must exist in this region of the Nuclide Chart, with some of the nuclei having unusually high ECDF probabilities. Therefore, this Proposal is intended to initiate the systematic identification and study of $\\beta$-delayed fission at ISOLDE in the very neutron-deficient lead region. Our aim is to provide unique low-energy fission data (e.g. probabilities, TKE release, fission barriers and their isospin dep...

  8. A study on the ultrastructure of the mouse kidney tissues affected by lead (Pb)

    International Nuclear Information System (INIS)

    Yoo, Chang Kyu; Choe, Rim Soon

    1986-01-01

    This study was made to investigate the ultrastructural changes of the male mouse(ICR strain) kidney tissue affected by lead(Pb). Pb, as a form of Pb(CH 3 COO) 2 was injected within the peritoneal cavity at the time interval of 24 hrs, 48 hrs and 72 hrs from injection time. In the meantime, electron microscopy was used to investigate the histologic changes occured in control animals, experimental animals. In kidney cells of experimental animals, changes of the nuclear chromatin were little, but cristae of mitochondria presented in cytoplasm was impaired, vacuolation was risen, thoseby many vacuole was formed. Especially, in the case of 5 mg/kg and 10 mg/kg Pb concentration, mitochondrial presented in cytoplasm was considerably deformed. While, with 20 mg/kg of Pb(CH 3 C00) 2 , it was observed that normal structure was presented in the nucleus electrodensity in cytoplasm was decreased mostly, but mitochondrial deform was slightly decreased. (Author)

  9. Experimental study of the Phenomenology of Spallation Neutrons in a large lead block

    International Nuclear Information System (INIS)

    Gonzalez, E.

    1997-01-01

    The TARC Experiment is the second phase of the experimental program associated to the Energy Amplifier (EA) [1]. In the first experiment, FEAT [2], the amplification of the energy supplied by a proton beam, by means of a subcritical device, was measured and an excellent agreement was found with the prediction of the Monte Carlo developed for the EA project. Two critical aspects of the present concepts and applications of the EA are Targeted by TARC. First the study of the spallation and neutron transport in a large volume of pure lead, and second, the verification of the enhanced isotope transmutation inside the EA, by the Adiabatic Resonance Crossing mechanism. Both the data and the comparison with the predictions based on the presently available data bases and MC programs, provide useful information for the development of the ADS concepts. The TARC collaboration has collected a comprehensive and redundant set of high quality data on neutron fluxes and transmutation rates, that will provide a precise understanding of the subjacent basic process and an excellent benchmark for ADS simulation systems. At present we are finishing the detailed data analysis and starting the comparison with the predictions of the EA MC. In this sense all the data presented in this communication are still preliminary. (Author) 3 refs

  10. Comparative Study of Breakdown Voltage of Mineral, Synthetic and Natural Oils and Based Mineral Oil Mixtures under AC and DC Voltages

    Directory of Open Access Journals (Sweden)

    Abderrahmane Beroual

    2017-04-01

    Full Text Available This paper deals with a comparative study of AC and DC breakdown voltages of based mineral oil mixtures with natural and synthetic esters mainly used in high voltage power transformers. The goal was to analyze the performances of oil mixtures from the dielectric withstand point of view and to predict the behavior of transformers originally filled with mineral oil and re-filled with synthetic or natural ester oils when emptied for maintenance. The study concerns mixtures based on 20%, 50%, and 80% of natural and synthetic ester oils. AC breakdown voltages were measured using a sphere-sphere electrode system according to IEC 60156 specifications; the same specification was adopted for DC measurements since there is no standard specifications for this voltage waveform. A statistical analysis of the mean values, standard deviations, and histograms of breakdown voltage data was carried out. The Normal and Weibull distribution functions were used to analyze the experimental data and the best function that the data followed was used to estimate the breakdown voltage with risk of 1%, 10%, and 50% probability. It was shown that whatever the applied voltage waveforms, ester oils always have a significantly higher breakdown voltage than mineral oil. The addition of only 20% of natural or synthetic ester oil was sufficient to considerably increase the breakdown voltage of mineral oil. The dielectric strength of such a mixture is much higher than that of mineral oil alone and can reach that of ester oils. From the point of view of dielectric strength, the mixtures constitute an option for improving the performance of mineral oil. Thus, re-filling of transformers containing up to 20% mineral oil residues with ester oils, does not present any problem; it is even advantageous when considering only the breakdown voltage. Under AC, the mixtures with natural ester always follow the behavior of vegetable oil alone. With the exception of the 20% mixture of natural

  11. Soil Lead Testing at a High Spatial Resolution in an Urban Community Garden: A Case Study in Relic Lead in Terre Haute, Indiana.

    Science.gov (United States)

    Latimer, Jennifer C; Van Halen, David; Speer, James; Krull, Stephanie; Weaver, Patricia; Pettit, Joseph; Foxx, Heather

    2016-10-01

    Industrial emissions, deteriorating or improperly removed lead paint, and the use of lead additives in fuel have left a substantial burden of heavy metals, such as lead, in urban soils. Much of this lead remains near the surface where it has the potential to impact human health. Exposure to lead, especially in children, can have lasting impacts on neurological development and academic achievement. Urban gardening, in particular, is an activity that could result in increased exposure to soil lead for many unsuspecting gardeners. During the summer of 2012, more than 1,061 surface soil samples were collected from an approximately 1.25 acre urban community garden in Terre Haute, Indiana. Samples were collected to evaluate the spatial distribution of lead across the community garden on the plot level. The results highlight the variability that can be seen within small areas of a former residential property, for example lead concentrations that are low (garden plot as concentrations that are considered high (>600 ppm). Based on the results of this work, several areas of concern were identified and the community garden was reconfigured to reduce potential lead exposure to gardeners and the local community.

  12. Lead adsorption study on combustion derived γ-Fe2O3 surface

    Indian Academy of Sciences (India)

    2016-08-26

    AAS) and solution conductivity (SC). Reduction in the concentration and increase in conductance of eluent lead solution is observed. The potential use of solid adsorbents for the adsorption of heavy metal pollutants is envisaged ...

  13. Degradation patterns of natural and synthetic textiles on a soil surface during summer and winter seasons studied using ATR-FTIR spectroscopy

    Science.gov (United States)

    Ueland, Maiken; Howes, Johanna M.; Forbes, Shari L.; Stuart, Barbara H.

    2017-10-01

    Textiles are a valuable source of forensic evidence and the nature and condition of textiles collected from a crime scene can assist investigators in determining the nature of the death and aid in the identification of the victim. Until now, much of the knowledge of textile degradation in forensic contexts has been based on the visual inspection of material collected from soil environments. The purpose of the current study was to investigate the potential of a more quantitative approach to the understanding of forensic textile degradation through the application of infrared spectroscopy. Degradation patterns of natural and synthetic textile materials as they were subjected to a natural outdoor environment in Australia were investigated. Cotton, polyester and polyester - cotton blend textiles were placed on a soil surface during the summer and winter seasons and were analysed over periods 1 and 1.5 years, respectively, and examined using attenuated total reflectance (ATR) spectroscopy. Statistical analysis of the spectral data obtained for the cotton material correlated with visual degradation and a difference in the onset of degradation between the summer and winter season was revealed. The synthetic material did not show any signs of degradation either visually or statistically throughout the experimental period and highlighted the importance of material type in terms of preservation. The cotton section from the polyester - cotton blend samples was found to behave in a similar manner to that of the 100% cotton samples, however principal component analysis (PCA) demonstrated that the degradation patterns were less distinct in both the summer and winter trial for the blend samples. These findings indicated that the presence of the synthetic material may have inhibited the degradation of the natural material. The use of statistics to analyse the spectral data obtained for textiles of forensic interest provides a better foundation for the interpretation of the data

  14. Lead (Pb) bioaccumulation; genera Bacillus isolate S1 and SS19 as a case study

    Science.gov (United States)

    Arifiyanto, Achmad; Apriyanti, Fitria Dwi; Purwaningsih, Puput; Kalqutny, Septian Hary; Agustina, Dyah; Surtiningsih, Tini; Shovitri, Maya; Zulaika, Enny

    2017-06-01

    Lead (Pb) includes a group of large heavy metal in nature was toxic either on animal or human and did not provide an advantage function biologically. Bacillus isolates S1 and SS19 known resistant to lead up to 50 mg / L PbCl2. In this research will be examined whether genera Bacillus isolates S1 and SS19 could accumulate metal lead (Pb), their capability in accumulating and profile protein differences when the bacteria genera Bacillus isolates S1 and SS19 get exposed metal lead (Pb). Inoculum at age ± 9 hours are used, with a Nutrient Broth (NB) containing 50, 75 and 100 mg / L PbCl2. Inductively Coupled Plasma Atomic Emission Spectrometry (ICP) used to assessed Pb2+ concentrations. Bioaccumulation levels of Pb2+ by Bacillus isolate S1 and SS19 related to the distinction of beginning concentration to the final concentration. Bacillus isolate S1 achieved 53% and 51% bioaccumulation efficiency rate in lead presence concentration (75 and 100 mg/L) and 51% (50 mg/L). Another way Bacillus isolate SS19 was able to accumulate 57% (50 mg/L PbCl2) and kept stable on 36% bioaccumulation efficiency rate (75 and 100 mg/L PbCl2). Regarding SDS-PAGE electrophoresis protein profile result, protein in ± 127 kDa, molecule mass detected in the presence of Lead for Bacillus isolate S1.

  15. Is lead shielding of patients necessary during fluoroscopic procedures? A study based on kyphoplasty

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Joshua R.; Marsh, Rebecca M.; Silosky, Michael S. [University of Colorado School of Medicine, Department of Radiology, Aurora, CO (United States)

    2018-01-15

    To determine the benefits, risks, and limitations associated with wrapping a patient with lead shielding during fluoroscopy-guided kyphoplasty procedures as a way to reduce operator radiation exposure. An anthropomorphic phantom was used to mimic a patient undergoing a kyphoplasty procedure under fluoroscopic guidance. Radiation measurements of the air kerma rate (AKR) were made at several locations and under various experimental conditions. First, AKR was measured at various angles along the horizontal plane of the phantom and at varying distances from the phantom, both with and without a lead apron wrapped around the lower portion of the phantom (referred to here as phantom shielding). Second, the effect of an operator's apron was simulated by suspending a lead apron between the phantom and the measurement device. AKR was measured for the four shielding conditions - phantom shielding only, operator apron only, both phantom shielding and operator apron, and no shielding. Third, AKR measurements were made at various heights and with varying C-arm angle. At all locations, the phantom shielding provided no substantial protection beyond that provided by an operator's own lead apron. Phantom shielding did not reduce AKR at a height comparable to that of an operator's head. Previous reports of using patient shielding to reduce operator exposure fail to consider the role of an operator's own lead apron in radiation protection. For an operator wearing appropriate personal lead apparel, patient shielding provides no substantial reduction in operator dose. (orig.)

  16. Structural and luminescence studies on Dy3+ doped lead boro-telluro-phosphate glasses

    Science.gov (United States)

    Selvi, S.; Venkataiah, G.; Arunkumar, S.; Muralidharan, G.; Marimuthu, K.

    2014-12-01

    This paper reports results obtained on the structural and luminescence properties of Dy3+doped lead boro-telluro-phosphate glasses prepared following the melt quenching technique. FTIR spectra exhibit the presence of B-O vibrations, P-O-P symmetric vibrations and Te-O stretching modes of TeO3 and TeO6 units. The metal-ligand bond was identified through UV-vis-NIR absorption spectra and to determine the band tailing parameter, direct and indirect band gap energy of the prepared glasses. The Judd-Ofelt (JO) intensity parameters (Ω2, Ω4 and Ω6), experimental and theoretical oscillator strengths were also determined and reported. Luminescence measurements were made to determine the transition probability (A), stimulated emission cross-section (σPE) and branching ratio (βR) for the transitions that include 4F9/2→6H11/2, 6H13/2 and 6H15/2 bands. The effect of Dy3+ ion concentration on the intensity ratio of yellow to blue emission bands has also been studied and reported. The lifetime corresponding to the 4F9/2 level of the title glasses has been found to decrease with the increase in Dy3+ ion concentration. The chromaticity coordinates (x,y) have been estimated from the luminescence spectra and the suitability of title glasses for white light applications has been analyzed using CIE chromaticity diagram. The variation of optical properties with the concentration of dysprosium oxide content in the glasses have been studied and reported.

  17. Structural and luminescence studies on Dy{sup 3+} doped lead boro–telluro-phosphate glasses

    Energy Technology Data Exchange (ETDEWEB)

    Selvi, S. [Department of Physics, Gandhigram Rural University, Gandhigram 624302 (India); Venkataiah, G. [Department of Physics, Sri Venkateswara University, Tirupati 517502 (India); Arunkumar, S.; Muralidharan, G. [Department of Physics, Gandhigram Rural University, Gandhigram 624302 (India); Marimuthu, K., E-mail: mari_ram2000@yahoo.com [Department of Physics, Gandhigram Rural University, Gandhigram 624302 (India)

    2014-12-01

    This paper reports results obtained on the structural and luminescence properties of Dy{sup 3+}doped lead boro−telluro-phosphate glasses prepared following the melt quenching technique. FTIR spectra exhibit the presence of B−O vibrations, P−O−P symmetric vibrations and Te−O stretching modes of TeO{sub 3} and TeO{sub 6} units. The metal–ligand bond was identified through UV−vis−NIR absorption spectra and to determine the band tailing parameter, direct and indirect band gap energy of the prepared glasses. The Judd−Ofelt (JO) intensity parameters (Ω{sub 2}, Ω{sub 4} and Ω{sub 6}), experimental and theoretical oscillator strengths were also determined and reported. Luminescence measurements were made to determine the transition probability (A), stimulated emission cross-section (σ{sub P}{sup E}) and branching ratio (β{sub R}) for the transitions that include {sup 4}F{sub 9/2}→{sup 6}H{sub 11/2}, {sup 6}H{sub 13/2} and {sup 6}H{sub 15/2} bands. The effect of Dy{sup 3+} ion concentration on the intensity ratio of yellow to blue emission bands has also been studied and reported. The lifetime corresponding to the {sup 4}F{sub 9/2} level of the title glasses has been found to decrease with the increase in Dy{sup 3+} ion concentration. The chromaticity coordinates (x,y) have been estimated from the luminescence spectra and the suitability of title glasses for white light applications has been analyzed using CIE chromaticity diagram. The variation of optical properties with the concentration of dysprosium oxide content in the glasses have been studied and reported.

  18. Interrupted time series analysis of children’s blood lead levels: A case study of lead hazard control program in Syracuse, New York

    Science.gov (United States)

    Shao, Liyang; Zhang, Lianjun; Zhen, Zhen

    2017-01-01

    Children’s blood lead concentrations have been closely monitored over the last two decades in the United States. The bio-monitoring surveillance data collected in local agencies reflected the local temporal trends of children’s blood lead levels (BLLs). However, the analysis and modeling of the long-term time series of BLLs have rarely been reported. We attempted to quantify the long-term trends of children’s BLLs in the city of Syracuse, New York and evaluate the impacts of local lead poisoning prevention programs and Lead Hazard Control Program on reducing the children’s BLLs. We applied interrupted time series analysis on the monthly time series of BLLs surveillance data and used ARMA (autoregressive and moving average) models to measure the average children’s blood lead level shift and detect the seasonal pattern change. Our results showed that there were three intervention stages over the past 20 years to reduce children’s BLLs in the city of Syracuse, NY. The average of children’s BLLs was significantly decreased after the interventions, declining from 8.77μg/dL to 3.94μg/dL during1992 to 2011. The seasonal variation diminished over the past decade, but more short term influences were in the variation. The lead hazard control treatment intervention proved effective in reducing the children’s blood lead levels in Syracuse, NY. Also, the reduction of the seasonal variation of children’s BLLs reflected the impacts of the local lead-based paint mitigation program. The replacement of window and door was the major cost of lead house abatement. However, soil lead was not considered a major source of lead hazard in our analysis. PMID:28182688

  19. Where Synthetic Biology Meets ET

    Science.gov (United States)

    Rothschild, Lynn J.

    2016-01-01

    Synthetic biology - the design and construction of new biological parts and systems and the redesign of existing ones for useful purposes - has the potential to transform fields from pharmaceuticals to fuels. Our lab has focused on the potential of synthetic biology to revolutionize all three major parts of astrobiology: Where do we come from? Where are we going? and Are we alone? For the first and third, synthetic biology is allowing us to answer whether the evolutionary narrative that has played out on planet earth is likely to have been unique or universal. For example, in our lab we are re-evolving the biosynthetic pathways of amino acids in order to understand potential capabilities of an early organism with a limited repertoire of amino acids and developing techniques for the recovery of metals from spent electronics on other planetary bodies. And what about the limits for life? Can we create organisms that expand the envelope for life? In the future synthetic biology will play an increasing role in human activities both on earth, in fields as diverse as human health and the industrial production of novel bio-composites. Beyond earth, we will rely increasingly on biologically-provided life support, as we have throughout our evolutionary history. In order to do this, the field will build on two of the great contributions of astrobiology: studies of the origin of life and life in extreme environments.

  20. Feasibility study on commercialization of fast breeder reactor cycle system. Interim report of phase 2. Technical study report on synthetic evaluation for FBR cycle

    International Nuclear Information System (INIS)

    Shiotani, Hiroki; Ohtaki, Akira; Ono, Kiyoshi; Yasumatsu, Naoto; Kubota, Sadae; Heta, Masanori

    2004-09-01

    This report presents the outline of the development and the results of Synthetic evaluation on the candidate Fast Reactor (FR) cycle system concepts, scenario study on FR cycle deployment and cost-benefit analysis on the candidate FR cycle system concepts in the interim evaluation (FY2001 through FY2003) of the phase 2 of the Japanese 'Feasibility Study on Commercialization of Fast Reactor Cycle System (FS)'. The characteristic evaluation extended to evaluate a new view point of social acceptance besides the viewpoints of safety, economics, reduction of environmental burden, efficient utilization of uranium resource, proliferation resistance, and technical feasibility, which has been considered since the phase 1 of FS. As for the six view points, hierarchy structures and utility functions for quantitative evaluation have been developed and/or improved. Furthermore, the methodology for weighing the viewpoints, which was also developed, made it possible to examine the characteristics of the candidate concepts from all the seven viewpoints. Generally, the FR cycles with sodium-cooled FR were highly evaluated. The characteristic evaluation for alternative power supply systems was also tried in this report for the first time. FR cycle deployment scenarios clarified the necessity of FR cycle deployment and the desirable core features, etc. through the long-term mass flow analysis, which includes comparison among other nuclear fuel cycle schemes and analysis for evaluating the degree to meet future needs, on the typical FR cycle systems. Regarding cost-benefit analysis, both the amount of the cost estimated by the past R and D and the cost in the Road map of FS are used as the investment for FR cycle research and development (R and D), the results showed that the benefit derived from the commercialization of FR cycle will be more than the investment. (author)