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Zaleski R, Embry M, McKee R, Teuschler LK. Exploring the utility of the Threshold of Toxicological Concern (TTC) as a screening approach for complex substances. Regul Toxicol Pharmacol 2021; 127:105051. [PMID: 34614434 DOI: 10.1016/j.yrtph.2021.105051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 09/10/2021] [Accepted: 09/29/2021] [Indexed: 11/28/2022]
Abstract
The Threshold of Toxicological Concern (TTC) has been applied to assess chemical safety for use, particularly in the food safety area. Although the TTC was developed for application to an individual chemical structure, more recently this concept has been suggested for the assessment of combined exposures to multiple chemicals. This study evaluated the potential for applying the TTC to a specific type of co-exposure, that of a complex substance of variable composition which contains multiple constituents, following the World Health Organization/International Programme on Chemical Safety framework for risk assessment of combined exposure to multiple chemicals. The results indicated that the TTC threshold was lower (i.e., more conservative) than regulatory thresholds derived for the same substance or even its most toxic constituent, providing assurance that the TTC could meet the requirements for a conservative screening process. This case study indicates that the TTC concept can be a useful tool to screen for potential risks from complex substances, with the consideration of additional aspects such as variability in chemical constituents and their relative proportions within the substance.
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Affiliation(s)
- R Zaleski
- ExxonMobil Biomedical Sciences Inc, 1545 Route 22 East, Annandale, NJ, 08801, USA.
| | - M Embry
- Health and Environmental Sciences Institute, 740 15th Street NW, Suite 600, Washington, DC, 20005, USA.
| | - R McKee
- ExxonMobil Biomedical Sciences Inc, 1545 Route 22 East, Annandale, NJ, 08801, USA; Hillsborough, NJ, USA.
| | - L K Teuschler
- LK Teuschler & Associates, 6634 Tenth Avenue Terr So, St. Petersburg, FL, 33707, USA.
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2
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Pietrow M, Zaleski R, Wagner A, Słomski P, Hirschmann E, Krause-Rehberg R, Liedke MO, Butterling M, Weinberger D. An experimental investigation of light emission produced in the process of positronium formation in matter. Phys Chem Chem Phys 2021; 23:11264-11271. [PMID: 33950060 DOI: 10.1039/d1cp00755f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The excess energy emitted during the positronium (Ps) formation in condensed matter may be released as light. Spectroscopic analysis of this light can be a new method of studying the electronic properties of materials. We report the first experimental attempt, according to our knowledge, to verify the existence of this emission process. As a result, the possibility of the emission of photons during Ps formation is within the experimental uncertainty in two different solids: an n-alkane and porous silica. However, it seems that the Ps formation on the alkane surface is not accompanied by the emission of photons with energy in the detection range of 1.6-3.8 eV. Various processes that can influence the energy of the photon emitted during the Ps formation are discussed to elucidate this issue. To aid future experiments, equations were developed to estimate the expected ratio of light emission events to annihilation events with the presence or absence of a photon during the Ps formation.
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Affiliation(s)
- M Pietrow
- Institute of Physics, M. Curie-Skłodowska University, ul. Pl. M. Curie-Skłodowskiej 1, 20-031 Lublin, Poland.
| | - R Zaleski
- Institute of Physics, M. Curie-Skłodowska University, ul. Pl. M. Curie-Skłodowskiej 1, 20-031 Lublin, Poland.
| | - A Wagner
- Institut für Strahlenphysik/Institute of Radiation Physics, Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstr. 400, 01328 Dresden, Germany
| | - P Słomski
- IT Company Martinex, ul. Mełgiewska 95, 21-040 Swidnik, Poland
| | - E Hirschmann
- Institut für Strahlenphysik/Institute of Radiation Physics, Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstr. 400, 01328 Dresden, Germany
| | - R Krause-Rehberg
- Institut für Physik, Universität Halle, von-Danckelmann-Platz 3, 06120 Halle, Germany
| | - M O Liedke
- Institut für Strahlenphysik/Institute of Radiation Physics, Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstr. 400, 01328 Dresden, Germany
| | - M Butterling
- Institut für Strahlenphysik/Institute of Radiation Physics, Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstr. 400, 01328 Dresden, Germany
| | - D Weinberger
- Institut für Strahlenphysik/Institute of Radiation Physics, Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstr. 400, 01328 Dresden, Germany
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Dryzek E, Juszyńska-Gałązka E, Zaleski R, Jasińska B, Eusébio MES. Free volume in the smectic-E phase of 4-hexyl-4' isothiocyanatobiphenyl studied by positron annihilation spectroscopy. Phys Rev E 2020; 101:022705. [PMID: 32168647 DOI: 10.1103/physreve.101.022705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 01/08/2020] [Indexed: 06/10/2023]
Abstract
Positron annihilation lifetime spectroscopy has been used to study 4-hexyl-4'-isothiocyanatobiphenyl. Changes of the orthopositronium lifetime parameters with temperature have been observed for the supercooled smectic-E phase. The measurements confirm that positronium is created and annihilates in a layer of a lower electron density containing alkyl chains of molecules. The two-state bond-lattice model of glass transition explains the thermal activation of the centers where orthopositronium is created and annihilates when the glass of the smectic-E phase softens. However, the subsequent cold crystallization of the softened regions also influences the orthopositronium lifetime and intensity, which complicates the picture seen by positrons. The measurements during isothermal crystallization suggest that it progresses in two stages. The first stage can be described by the Avrami equation with the Avrami exponent close to unity, which indicates low-dimensional crystallization. Similarly to liquid n alkanes, the application of pressure is equivalent to temperature lowering with the similar equivalence relationship between pressure and temperature, which seems to confirm the structure of the smectic-E phase with sublayers containing alkyl chains in a molten state. The dependence of the orthopositronium lifetime on pressure for the smectic-E phase may be described by the bubble model where the positronium bubble is approximated with a finite square potential well with the depth of U=1.45eV.
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Affiliation(s)
- E Dryzek
- Institute of Nuclear Physics, Polish Academy of Sciences, 31-342 Kraków, Poland
| | - E Juszyńska-Gałązka
- Institute of Nuclear Physics, Polish Academy of Sciences, 31-342 Kraków, Poland
| | - R Zaleski
- Institute of Physics, Maria Curie-Skłodowska University, Pl. M. Curie-Skłodowskiej 1, 20-031 Lublin, Poland
| | - B Jasińska
- Institute of Physics, Maria Curie-Skłodowska University, Pl. M. Curie-Skłodowskiej 1, 20-031 Lublin, Poland
| | - M E S Eusébio
- CQC Departamento de Quimica, Universidade de Coimbra, Rua Larga 3004-534 Coimbra, Portugal
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Korcyl G, Bialas P, Curceanu C, Czerwinski E, Dulski K, Flak B, Gajos A, Glowacz B, Gorgol M, Hiesmayr BC, Jasinska B, Kacprzak K, Kajetanowicz M, Kisielewska D, Kowalski P, Kozik T, Krawczyk N, Krzemien W, Kubicz E, Mohammed M, Niedzwiecki S, Pawlik-Niedzwiecka M, Palka M, Raczynski L, Rajda P, Rudy Z, Salabura P, Sharma NG, Sharma S, Shopa RY, Skurzok M, Silarski M, Strzempek P, Wieczorek A, Wislicki W, Zaleski R, Zgardzinska B, Zielinski M, Moskal P. Evaluation of Single-Chip, Real-Time Tomographic Data Processing on FPGA SoC Devices. IEEE Trans Med Imaging 2018; 37:2526-2535. [PMID: 29994248 DOI: 10.1109/tmi.2018.2837741] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
A novel approach to tomographic data processing has been developed and evaluated using the Jagiellonian positron emission tomography scanner as an example. We propose a system in which there is no need for powerful, local to the scanner processing facility, capable to reconstruct images on the fly. Instead, we introduce a field programmable gate array system-on-chip platform connected directly to data streams coming from the scanner, which can perform event building, filtering, coincidence search, and region-of-response reconstruction by the programmable logic and visualization by the integrated processors. The platform significantly reduces data volume converting raw data to a list-mode representation, while generating visualization on the fly.
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Bartoš J, Zgardzinska B, Švajdlenková H, Lukešová M, Zaleski R. ESR and PALS detection of the dynamic crossover in the supercooled liquid states of short and medium-sized n-alkanes. Chem Phys Lett 2018. [DOI: 10.1016/j.cplett.2018.04.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Dellarco M, Zaleski R, Gaborek BJ, Qian H, Bellin CA, Egeghy P, Heard N, Jolliet O, Lander DR, Sunger N, Stylianou KS, Tanir JY. Using exposure bands for rapid decision making in the RISK21 tiered exposure assessment. Crit Rev Toxicol 2017; 47:317-341. [PMID: 28266262 PMCID: PMC6091571 DOI: 10.1080/10408444.2016.1270255] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The ILSI Health and Environmental Sciences Institute (HESI) Risk Assessment in the Twenty-first Century (RISK21) project was initiated to address and catalyze improvements in human health risk assessment. RISK21 is a problem formulation-based conceptual roadmap and risk matrix visualization tool, facilitating transparent evaluation of both hazard and exposure components. The RISK21 roadmap is exposure-driven, that is, exposure is used as the second step (after problem formulation) to define and focus the assessment. This paper describes the exposure tiers of the RISK21 matrix and the approaches to adapt readily available information to more quickly inform exposure at a screening level. In particular, exposure look-up tables were developed from available exposure tools (European Centre for Ecotoxicology and Toxicology of Chemicals (ECETOC) Targeted Risk Assessment (TRA) for worker exposure, ECETOC TRA, European Solvents Industry Group (ESIG) Generic Exposure Scenario (GES) Risk and Exposure Tool (EGRET) for consumer exposure, and USEtox® for indirect exposure to humans via the environment) and were tested in a hypothetical mosquito bed netting case study. A detailed WHO risk assessment for a similar mosquito net use served as a benchmark for the performance of the RISK21 approach. The case study demonstrated that the screening methodologies provided suitable conservative exposure estimates for risk assessment. The results of this effort showed that the RISK21 approach is useful for defining future assessment efforts, focusing assessment activities and visualizing results.
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Affiliation(s)
- M Dellarco
- a National Children?s Study, Eunice Kennedy Shriver National Institute of Child Health and Human Development , Bethesda , MD , USA
| | - R Zaleski
- b Occupational and Public Health Division, ExxonMobil Biomedical Sciences, Inc , Annandale , NJ , USA
| | - B J Gaborek
- c DuPont Haskell Global Centers for Health and Environmental Sciences, DuPont , Newark , DE , USA
| | - H Qian
- b Occupational and Public Health Division, ExxonMobil Biomedical Sciences, Inc , Annandale , NJ , USA
| | - C A Bellin
- c DuPont Haskell Global Centers for Health and Environmental Sciences, DuPont , Newark , DE , USA
| | - P Egeghy
- d National Exposure Research Laboratory , U.S. Environmental Protection Agency, Research Triangle Park , NC , USA
| | - N Heard
- e Product Safety, Operator and Consumer Safety, Syngenta Crop Protection LLC , Greensboro , NC , USA
| | - O Jolliet
- f Department of Environmental Health Sciences , University of Michigan , Ann Arbor , MI , USA
| | - D R Lander
- c DuPont Haskell Global Centers for Health and Environmental Sciences, DuPont , Newark , DE , USA
| | - N Sunger
- g Toxicology and Environmental Research & Consulting, The Dow Chemical Company , Midland , MI , USA
| | - K S Stylianou
- f Department of Environmental Health Sciences , University of Michigan , Ann Arbor , MI , USA
| | - J Y Tanir
- h ILSI Health and Environmental Sciences Institute , Washington , DC , USA
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Kowalewska A, Nowacka M, Włodarska M, Zgardzińska B, Zaleski R, Oszajca M, Krajenta J, Kaźmierski S. Solid-state dynamics and single-crystal to single-crystal structural transformations in octakis(3-chloropropyl)octasilsesquioxane and octavinyloctasilsesquioxane. Phys Chem Chem Phys 2017; 19:27516-27529. [DOI: 10.1039/c7cp05233b] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Thermally induced formation of symmetric crystal lattices in functional POSS proceeds via different mechanisms and results in unique reversible phenomena.
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Affiliation(s)
- A. Kowalewska
- Centre of Molecular and Macromolecular Studies
- Polish Academy of Sciences
- 90-363 Łódź
- Poland
| | - M. Nowacka
- Centre of Molecular and Macromolecular Studies
- Polish Academy of Sciences
- 90-363 Łódź
- Poland
| | - M. Włodarska
- Institute of Physics
- Lodz University of Technology
- 90-924 Łódź
- Poland
| | - B. Zgardzińska
- Department of Nuclear Methods
- Institute of Physics
- Maria Curie-Sklodowska University
- 20-031 Lublin
- Poland
| | - R. Zaleski
- Department of Nuclear Methods
- Institute of Physics
- Maria Curie-Sklodowska University
- 20-031 Lublin
- Poland
| | - M. Oszajca
- Jagiellonian University
- Faculty of Chemistry
- 30-060 Kraków
- Poland
| | - J. Krajenta
- Centre of Molecular and Macromolecular Studies
- Polish Academy of Sciences
- 90-363 Łódź
- Poland
| | - S. Kaźmierski
- Centre of Molecular and Macromolecular Studies
- Polish Academy of Sciences
- 90-363 Łódź
- Poland
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8
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Dryzek E, Juszyńska E, Zaleski R, Jasińska B, Gorgol M, Massalska-Arodź M. Positron annihilation studies of 4-n-butyl-4'-isothiocyanato-1,1'-biphenyl. Phys Rev E Stat Nonlin Soft Matter Phys 2013; 88:022504. [PMID: 24032853 DOI: 10.1103/physreve.88.022504] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Indexed: 06/02/2023]
Abstract
Positron annihilation lifetime spectroscopy (PALS) measurements were performed between 93 and 293 K in order to study the supercooled smectic-E (Sm-E) phase of 4-n-butyl-4'-isothiocyanato-1,1'-biphenyl (4TCB), the ordered molecular crystal of 4TCB, and the phase transition between the Sm-E phase and the ordered molecular crystal of 4TCB. The phase transition was well reflected in the abrupt increase of the ortho-positronium (o-Ps) lifetime and intensity. The value of the o-Ps lifetime in the Sm-E liquid crystalline phase of 4TCB, i.e., 2.21 ns at room temperature, was explained by the formation of bubbles induced by Ps atoms, which are created due to a liquidlike state of the butyl chains of 4TCB molecules in the Sm-E phase. The temperature dependence of the o-Ps intensity for the supercooled Sm-E phase can be explained by thermal generation of sites where bubbles are formed; an activation energy equal to 0.30±0.02 eV was estimated. This value was compared with the activation energies of molecular motions. The o-Ps lifetime in the ordered molecular crystal was interpreted as originating from the annihilation of o-Ps confined in molecular vacancy-type imperfections in the crystal lattice. The value of the o-Ps pickoff annihilation between 1.8 and 1.9 ns is in accordance with the size of the molecular vacancy for the 4TCB crystal lattice. Its intensity is lower than 5%. The isothermal crystallization of the 4TCB Sm-E phase was observed by PALS. The low-dimensional crystal growth was concluded from the Avrami equation fitted to the time dependence of the o-Ps intensity, which resulted in an Avrami exponent equal to 1.73.
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Affiliation(s)
- E Dryzek
- The H. Niewodniczański Institute of Nuclear Physics PAN, ul. Radzikowskiego 152, 31-342 Kraków, Poland
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Kierys A, Zaleski R, Buda W, Pikus S, Dziadosz M, Goworek J. Nanostructured polymer-titanium composites and titanium oxide through polymer swelling in titania precursor. Colloid Polym Sci 2012; 291:1463-1470. [PMID: 23741082 PMCID: PMC3669504 DOI: 10.1007/s00396-012-2881-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2012] [Revised: 11/02/2012] [Accepted: 12/09/2012] [Indexed: 11/28/2022]
Abstract
Polymer (XAD7HP)/Ti4+ nanocomposites were prepared through the swelling of polymer in titanium (IV) ethoxide as a titanium dioxide precursor. The nanocomposite beads exhibit relatively high porosity different than the porosity of the initial polymer. Thermal treatment of composite particles up to 200 °C in vacuum causes the change of their internal structure. At higher temperature, the components of composite become more tightly packed. Calcination at 600 °C and total removal of polymer produce spherically shaped TiO2 condensed phase as determined by XRD. Thermally treated composites show the substantial change of pore dimensions within micro- and mesopores. The presence of micropores and their transformation during thermal processing was studied successfully by positron annihilation lifetime spectroscopy (PALS). The results derived from PALS experiment were compared with those obtaining from low-temperature nitrogen adsorption data.
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Affiliation(s)
- A Kierys
- Department of Adsorption, Faculty of Chemistry, M. Curie-Sklodowska University, M. Curie-Sklodowska sq. 3, 20-031 Lublin, Poland
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Śniegocka M, Jasińska B, Goworek T, Zaleski R. Temperature dependence of o-Ps lifetime in some porous media. Deviations from ETE model. Chem Phys Lett 2006. [DOI: 10.1016/j.cplett.2006.09.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Goworek T, Zaleski R, Wawryszczuk J. Observation of intramolecular defects in n-alkanes C25H52–C29H60 by the positron annihilation method. Chem Phys Lett 2004. [DOI: 10.1016/j.cplett.2004.06.116] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Goworek T, Zaleski R, Wawryszczuk J. Temperature, pressure and source-irradiation effects in positronium formation in some solid long-chain alkanes. Chem Phys 2003. [DOI: 10.1016/j.chemphys.2003.08.019] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Goworek T, Wawryszczuk J, Zaleski R. Ortho-Ps annihilation in resorcinol at high pressure. Radiat Phys Chem Oxf Engl 1993 2003. [DOI: 10.1016/s0969-806x(03)00235-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Zaleski R, Wawryszczuk J, Goworek J, Borówka A, Goworek T. Vacuum removal of the template in MCM-41 silica studied by the positron annihilation method. J Colloid Interface Sci 2003; 262:466-73. [PMID: 16256627 DOI: 10.1016/s0021-9797(03)00206-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2002] [Accepted: 02/20/2003] [Indexed: 10/27/2022]
Abstract
Positron annihilation lifetime spectra were measured for ordered silica before template (octadecyltrimethyl ammonium) removal. An intermediate lifetime component, well pronounced in the spectra, indicates the presence of structural defects in the template being the size of a surfactant molecule. At the temperature near 420 K a radical change of template structure occurs, consisting in appearance of disorder and the degradation of template; evaporation of the fragments begins. It seems that moderate heating (up to about 500 K only) in vacuum for several hours is an effective and simple method of template removal, leaving no pure carbon residue in the pore structure. The results are compared with the data from the liquid nitrogen adsorption/desorption method and elemental analysis, confirming the positron annihilation results.
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Affiliation(s)
- R Zaleski
- Institute of Physics, Maria Curie Sklodowska University, 20-031 Lublin, Poland
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Goworek T, Jasińska B, Wawryszczuk J, Zaleski R, Suzuki T. On possible deviations of experimental PALS data from positronium pick-off model estimates. Chem Phys 2002. [DOI: 10.1016/s0301-0104(02)00491-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Giles TD, Pina IL, Quiroz AC, Roffidal L, Zaleski R, Porter RS, Karalis DG, Mohrland JS, Wolf DL, Hearron AE. Hemodynamic and neurohumoral responses to intravenous nicorandil in congestive heart failure in humans. J Cardiovasc Pharmacol 1992; 20:572-8. [PMID: 1280713 DOI: 10.1097/00005344-199210000-00010] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Nicorandil is a vasodilator drug that combines potassium channel opening properties with nitrate effects. The resulting potent and unique vasodilating properties suggest a potential therapeutic role in congestive heart failure. We therefore studied the acute hemodynamic and neurohumoral responses to nicorandil, given as single intravenous bolus doses of 158, 251, 398, or 630 micrograms/kg, to 22 patients with chronic congestive heart failure (ejection fraction less than 40%). Hemodynamic responses occurred within 5 min of dosing and terminated within 240 min. The heart rate was significantly increased only at 5 min after the 158 micrograms/kg dose, and was unchanged after all other doses. The mean arterial pressure was reduced only by the 398 and 630 micrograms/kg doses. The pulmonary capillary wedge pressure and right atrial pressure were significantly reduced by all doses within the initial 30 min; this reduction in pulmonary capillary wedge pressure was better sustained over time by the two larger doses, whereas the reduction in right atrial pressure was sustained only by the 158 micrograms/kg dose. The cardiac index was reduced by the 158 micrograms/kg dose, but increased after 251, 398, and 630 micrograms/kg of nicorandil. Plasma nicorandil concentrations were positively correlated with changes in cardiac index, systemic arterial pressure, pulmonary capillary wedge pressure, heart rate, and systemic vascular resistance. When measured 1 h after dosing, plasma immunoreactive ANF decreased, norepinephrine concentrations did not change, and plasma renin activity increased, but only at the 630 micrograms/kg dose level.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- T D Giles
- Department of Medicine, Tulane University School of Medicine, New Orleans, Louisiana 70112
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Zaleski R. An automated pharmacy management system makes a difference. Comput Healthc 1983; 4:18-20. [PMID: 10259382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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Bukowczyk A, Pionkowski J, Szefel A, Zaleski R. [Erythrocytes in patients treated with neuroleptics]. Psychiatr Pol 1979; 13:97-101. [PMID: 36642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Pionkowski J, Szefel A, Zaleski R. [Types of mental disorders found in foreign students treated at a psychiatric hospital]. Psychiatr Pol 1979; 13:125-30. [PMID: 451099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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