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Benedetto A. Biomolecules, Water and Room-Temperature Ionic Liquids: Challenges and Opportunities in Basic Science and Applications. Biophys J 2017. [DOI: 10.1016/j.bpj.2016.11.2805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Girolami F, Spalenza V, Benedetto A, Manzini L, Badino P, Abete MC, Nebbia C. Comparative liver accumulation of dioxin-like compounds in sheep and cattle: Possible role of AhR-mediated xenobiotic metabolizing enzymes. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 571:1222-1229. [PMID: 27476725 DOI: 10.1016/j.scitotenv.2016.07.150] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Revised: 07/21/2016] [Accepted: 07/21/2016] [Indexed: 06/06/2023]
Abstract
PCDDs, PCDFs, and PCBs are persistent organic pollutants (POPs) that accumulate in animal products and may pose serious health problems. Those able to bind the aryl hydrocarbon receptor (AhR), eliciting a plethora of toxic responses, are defined dioxin-like (DL) compounds, while the remainders are called non-DL (NDL). An EFSA opinion has highlighted the tendency of ovine liver to specifically accumulate DL-compounds to a greater extent than any other farmed ruminant species. To examine the possible role in such an accumulation of xenobiotic metabolizing enzymes (XME) involved in DL-compound biotransformation, liver samples were collected from ewes and cows reared in an area known for low dioxin contamination. A related paper reported that sheep livers had about 5-fold higher DL-compound concentrations than cattle livers, while the content of the six marker NDL-PCBs did not differ between species. Specimens from the same animals were subjected to gene expression analysis for AhR, AhR nuclear translocator (ARNT) and AhR-dependent oxidative and conjugative pathways; XME protein expression and activities were also investigated. Both AhR and ARNT mRNA levels were about 2-fold lower in ovine samples and the same occurred for CYP1A1 and CYP1A2, being approximately 3- and 9-fold less expressed in sheep compared to cattle, while CYP1B1 could be detectable in cattle only. The results of the immunoblotting and catalytic activity (most notably EROD) measurements of the CYP1A family enzymes were in line with the gene expression data. By contrast, phase II enzyme expression and activities in sheep were higher (UGT1A) or similar (GSTA1, NQO1) to those recorded in cattle. The overall low expression of CYP1 family enzymes in the sheep is in line with the observed liver accumulation of DL-compounds and is expected to affect the kinetics and the dynamics of other POPs such as many polycyclic aromatic hydrocarbons, as well as of toxins (e.g. aflatoxins) or drugs (e.g. benzimidazole anthelmintics) known to be metabolized by those enzymes.
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Benedetto A, Kearley GJ. Elastic Scattering Spectroscopy (ESS): an Instrument-Concept for Dynamics of Complex (Bio-) Systems From Elastic Neutron Scattering. Sci Rep 2016; 6:34266. [PMID: 27703184 PMCID: PMC5050422 DOI: 10.1038/srep34266] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Accepted: 09/12/2016] [Indexed: 11/09/2022] Open
Abstract
A new type of neutron-scattering spectroscopy is presented that is designed specifically to measure dynamics in bio-systems that are difficult to obtain in any other way. The temporal information is largely model-free and is analogous to relaxation processes measured with dielectric spectroscopy, but provides additional spacial and geometric aspects of the underlying dynamics. Numerical simulations of the basic instrument design show the neutron beam can be highly focussed, giving efficiency gains that enable the use of small samples. Although we concentrate on continuous neutron sources, the extension to pulsed neutron sources is proposed, both requiring minimal data-treatment and being broadly analogous with dielectric spectroscopy, they will open the study of dynamics to new areas of biophysics.
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Brizio P, Benedetto A, Squadrone S, Curcio A, Pellegrino M, Ferrero M, Abete MC. Heavy metals and essential elements in Italian cereals. FOOD ADDITIVES & CONTAMINANTS PART B-SURVEILLANCE 2016; 9:261-267. [DOI: 10.1080/19393210.2016.1209572] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Benedetto A, Brizio P, Guaraldo P, Stella C, Cappa C, Baioni E, Spalenza V, Nebbia C, Abete MC. Dioxins, DL-PCB and NDL-PCB accumulation profiles in livers from sheep and cattle reared in North-western Italy. CHEMOSPHERE 2016; 152:92-98. [PMID: 26963240 DOI: 10.1016/j.chemosphere.2016.02.101] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2015] [Revised: 02/22/2016] [Accepted: 02/23/2016] [Indexed: 06/05/2023]
Abstract
Products of animal origin represent the main route of human exposure to dioxins and dioxin-like PCBs (DL-compounds). Recently, concerns have been raised about ovine products, particularly the liver, in which relatively high levels of DL-compounds have been reported. We surveyed ovine and bovine livers in areas with no known sources of dioxin or DL-PCB contamination, in order to assess accumulation patterns for both DL-compounds and non-DL (NDL-) PCBs. None of the ovine and bovine samples exceeded the current Maximum Limits (MLs) for DL-compounds. Liver DL-compound TEQ concentrations were up to 5-fold higher in sheep than in cows. No statistically significant differences in total NDL-PCBs levels were found. The main contributors to TEQ levels were the Penta- and Hexa-chlorinated PCDFs and PCB 126. The results confirm the increased bioaccumulation in ovine liver towards specific DL-compounds even in ewes reared in areas with no known sources of PCDD/Fs or DL-PCBs contamination.
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Benedetto A, Brizio P, Squadrone S, Scanzio T, Righetti M, Gasco L, Prearo M, Abete MC. Oxidative stress related to chlorpyrifos exposure in rainbow trout: Acute and medium term effects on genetic biomarkers. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2016; 129:63-69. [PMID: 27017883 DOI: 10.1016/j.pestbp.2015.10.019] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Revised: 10/21/2015] [Accepted: 10/21/2015] [Indexed: 06/05/2023]
Abstract
Organophosphates (OPs) are derivatives of phosphoric acid widely used in agriculture as pesticides. Chlorpyrifos (CPF) is an OP that is extremely toxic to aquatic organisms. Rainbow trout (Oncorhynchus mykiss) is considered as a sentinel model species for ecotoxicology assessment in freshwater ecosystems. An exposure study was carried out on rainbow trout to investigate genetic responses to CPF-induced oxidative stress by Real-Time PCR, and to determine the accumulation dynamics of CPF and toxic metabolite chlorpyrifos-oxon (CPF-ox) in edible parts, by HPLC-MS/MS. Among the genes considered to be related to oxidative stress, a significant increase in HSP70 mRNA levels was observed in liver samples up to 14 days after CPF exposure (0.05 mg/L). CPF concentrations in muscle samples reach mean values of 285.25 ng/g within 96 hours of exposure, while CPF-ox concentrations were always under the limit of quantification (LOQ) of the applied method. Our findings lead us to consider HSP70 as a suitable genetic marker in rainbow trout for acute and medium-term monitoring of CPF exposure, complementary to analytical determinations.
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Magazù S, Migliardo F, Benedetto A, La Torre R, Hennet L. Comments on: Bio-protective effects of homologous disaccharides on biological macromolecules. EUROPEAN BIOPHYSICS JOURNAL : EBJ 2016; 45:379. [PMID: 27015818 DOI: 10.1007/s00249-016-1124-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
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Benedetto A. Retraction notice to “Protein dynamics by neutron scattering” [Biophysical Chemistry 182 (2013) 16-22]. Biophys Chem 2016; 209:56. [DOI: 10.1016/j.bpc.2015.12.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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34
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Benedetto A, Bingham RJ, Ballone P. Structure and dynamics of POPC bilayers in water solutions of room temperature ionic liquids. J Chem Phys 2015; 142:124706. [DOI: 10.1063/1.4915918] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
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35
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Squadrone S, Benedetto A, Brizio P, Prearo M, Abete MC. Mercury and selenium in European catfish (Silurus glanis) from Northern Italian Rivers: can molar ratio be a predictive factor for mercury toxicity in a top predator? CHEMOSPHERE 2015; 119:24-30. [PMID: 25460744 DOI: 10.1016/j.chemosphere.2014.05.052] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Revised: 05/21/2014] [Accepted: 05/22/2014] [Indexed: 06/04/2023]
Abstract
The study of mercury and selenium bioaccumulation in fish is crucially important for evaluating the extent of contamination in freshwater environments, and the possible health risk posed for humans when the antagonistic interactions of these two elements are considered. Several factors affect the risk of mercury intake from fish consumption, including mercury levels, human consumption patterns, and sensitive populations (e.g., pregnant women, foetuses, young children and unknown genetic factors). The protective effects of selenium on mercury toxicity have been extensively publicised in recent years, particularly targeting fish consumers. In this study, mercury (Hg) and selenium (Se) concentrations were determined in the muscle of European catfish (Silurus glanis) collected from North Italian Rivers. Differences in mercury and selenium levels, as a function of size, gender and location were investigated. Hg was strongly related to length, gender and location, while Se levels are not dependent on fish size or location. The mean Se/Hg molar ratio was strongly affected by location, and significantly related to length and age. Selenium was in molar excess of mercury in all sites, with a rank order of mean Se/Hg molar ratio of the Parma River (2.55)>Po River (1.71)>Tanaro River (1.66)>Bormida River (1.36). However, in 37% of analyzed samples, Hg exceeded the maximum level set by 1881/2006/EC and 629/2008/EC in fish muscle. The molar ratio of Se/Hg was <1 only in the presence of significantly high Hg levels (>0.5mg/kg), and therefore the mean molar ratio cannot be considered as a safety criterion in top predator fish.
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Benedetto A, Heinrich F, Gonzalez MA, Fragneto G, Watkins E, Ballone P. Correction to “Structure and Stability of Phospholipid Bilayers Hydrated by a Room-Temperature Ionic Liquid/Water Solution: A Neutron Reflectometry Study”. J Phys Chem B 2014; 118:14990. [DOI: 10.1021/jp511974t] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Benedetto A, Heinrich F, Gonzalez MA, Fragneto G, Watkins E, Ballone P. Structure and Stability of Phospholipid Bilayers Hydrated by a Room-Temperature Ionic Liquid/Water Solution: A Neutron Reflectometry Study. J Phys Chem B 2014; 118:12192-206. [DOI: 10.1021/jp507631h] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Benedetto A, Bodo E, Gontrani L, Ballone P, Caminiti R. Amino acid anions in organic ionic compounds. An ab initio study of selected ion pairs. J Phys Chem B 2014; 118:2471-86. [PMID: 24494698 DOI: 10.1021/jp412281n] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The combination of amino acids in their deprotonated and thus anionic form with a choline cation gives origin to a new and potentially important class of organic ionic compounds. A series of such neutral ion pairs has been investigated by first principle methods. The results reveal intriguing structural motives as well as regular patterns in the charge distribution and predict a number of vibrational and optical properties that could guide the experimental investigation of these compounds. The replacement of choline with its phosphocholine analogue causes the spontaneous reciprocal neutralization of cations and anions, taking place through the transfer of a proton between the two ions. Systems of this kind, therefore, provide a wide and easily accessible playground to probe the ionic/polar transition in organic systems, while the easy transfer of H(+) among neutral and ionic species points to their potential application as proton conductors. The analysis of the ab initio data highlights similarities as well as discrepancies from the rigid-ions force-field picture and suggests directions for the improvement of empirical models.
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Benedetto A. Retraction of the article “Protein dynamics by neutron scattering” published in Biophysical Chemistry 2013, 182, 16–22. Biophys Chem 2014; 185:108. [DOI: 10.1016/j.bpc.2013.12.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2013] [Revised: 12/03/2013] [Accepted: 12/03/2013] [Indexed: 10/25/2022]
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Magazù S, Migliardo F, Benedetto A, Vertessy B. Protein dynamics by neutron scattering: The protein dynamical transition and the fragile-to-strong dynamical crossover in hydrated lysozyme. Chem Phys 2013. [DOI: 10.1016/j.chemphys.2013.03.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Benedetto A. Protein dynamics by neutron scattering. Biophys Chem 2013; 182:16-22. [PMID: 23953400 DOI: 10.1016/j.bpc.2013.07.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Revised: 07/15/2013] [Accepted: 07/17/2013] [Indexed: 10/26/2022]
Abstract
Neutron scattering techniques represent a powerful tool for characterizing both the structure and dynamical properties of bio-systems, for example, proteins and membranes interacting with their solvents. In this paper, Elastic Neutron Scattering (ENS) data collected at the Institut Laue-Langevin (Grenoble, France) on dry and D2O hydrated lysozyme by varying hydration level are presented, and compared with previously published data on the same protein system, also with the addition of bio-protectants. The data have been collected with three different spectrometers, i.e. IN13, IN10 and IN4. This set of ENS data gives direct access to the temperature behavior of both (i) the Mean Square Displacement (MSD) and (ii) the characteristic system relaxation time. As a result, an explicative hypothesis on the relationship between the so-called "protein dynamical transition" (PDT) and the "fragile-to-strong dynamical crossover" (FSC) is formulated. Furthermore, by taking into proper account the effect of the finite instrumental energy resolution of the used spectrometers, the vibrational MSD of dry and hydrated lysozyme is calculated. The vibrational MSD of the lysozyme in the dry state resulted to be higher than the one in the hydrated state; the latter reaches the former at a temperature value of T=220K that corresponds to the temperature at which the FSC occurs. As a result, a cage effect resulting from the hydration water on the protein surface is hypothesized and subsequently linked to the FSC.
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Squadrone S, Prearo M, Gavinelli S, Pellegrino M, Tarasco R, Benedetto A, Abete M. Heavy metals inMugil cephalus(Mugilidae) from the Ligurian Sea (North-West Mediterranean, Italy). FOOD ADDITIVES & CONTAMINANTS PART B-SURVEILLANCE 2013; 6:134-8. [DOI: 10.1080/19393210.2013.766817] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Squadrone S, Prearo M, Brizio P, Gavinelli S, Pellegrino M, Scanzio T, Guarise S, Benedetto A, Abete MC. Heavy metals distribution in muscle, liver, kidney and gill of European catfish (Silurus glanis) from Italian Rivers. CHEMOSPHERE 2013; 90:358-65. [PMID: 22901372 DOI: 10.1016/j.chemosphere.2012.07.028] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2012] [Revised: 06/29/2012] [Accepted: 07/12/2012] [Indexed: 05/25/2023]
Abstract
The accumulation of heavy metals in freshwaters has direct consequences to man and ecosystem. Thus, in this study, the concentrations of mercury, cadmium, lead, arsenic and chromium in organs of the predator European catfish (Silurus glanis) were investigated. Samples were collected annually in five sites covering the area of the Po River (North Italy) between 2007 and 2009. Metals were differently distributed in the various organs, the highest concentrations of Hg were found in muscle and liver, Cd in kidney, Pb in gill and liver, as in muscle, and of Cr in gill and liver. Our survey found Hg exceeding the Maximum Levels (MLs) of 0.5 ppm in 18% of samples, while Pb and Cd were lower than the MLs set by European regulations in muscle tissues (1881/2006/EC and 629/2008/EC). Hg concentrations were significantly related to sampling stations studied, according to the presence of many industrial activities in the catchment area of Bormida and Tanaro Rivers. The finding that Hg did not fit food fish legislation limits indicated that S. glanis flesh might not be utilised for human consumption. A close monitoring of metals pollution is strongly recommended especially in piscivorous fish, cause their bioaccumulation capacity.
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Pellegrino M, Brizio P, Gallina S, Tarasco R, Gavinelli S, Palmegiano P, Fioravanti F, Benedetto A, Squadrone S, Gallo G, Abete M. EXPORT OF CHEESE IN RUSSIA: THE ROLE OF IZSPLV. Ital J Food Saf 2012. [DOI: 10.4081/ijfs.2012.4.103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Coffe-Bart D, Izing A, Benedetto A. Accompagnement d’une entreprise de transport urbain dans la prévention des risques. Travail collaboratif sur l’ergonomie aux postes de conduite de bus. ARCH MAL PROF ENVIRO 2012. [DOI: 10.1016/j.admp.2012.03.215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Magazù S, Migliardo F, Benedetto A. Reply to “Comment on 'Puzzle of the Protein Dynamical Transition'”. J Phys Chem B 2012. [DOI: 10.1021/jp300926f] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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48
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Calvi A, Benedetto A, De Blasiis MR. A driving simulator study of driver performance on deceleration lanes. ACCIDENT; ANALYSIS AND PREVENTION 2012; 45:195-203. [PMID: 22269501 DOI: 10.1016/j.aap.2011.06.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2010] [Revised: 05/31/2011] [Accepted: 06/18/2011] [Indexed: 05/31/2023]
Abstract
Deceleration lanes are important because they help drivers transition from high-speed lanes to low-speed ramps. Although they are designed to allow vehicles to depart the freeway safely and efficiently, many studies report high accident rates on exit ramps with the highest percentage of crashes taking place in deceleration lanes. This paper describes the results of a driving simulator study that focused on driving performance while approaching a divergence area and decelerating during the exiting maneuver. Three different traffic scenarios were simulated to analyze the influence of traffic volume on driving performance. Thirty drivers drove in the simulator in these scenarios while data on their lateral position, speed and deceleration were collected. Our results indicate there are considerable differences between the main assumptions of models generally used to design deceleration lanes and actual driving performance. In particular, diverging drivers begin to decelerate before arriving at the deceleration lane, causing interference with the main flow. Moreover, speeds recorded at the end of the deceleration lane exceed those for which the ramp's curves are designed; this creates risky driving conditions that could explain the high crash rates found in studies of exit ramps. Finally, statistical analyses demonstrate significant influences of traffic volume on some aspects of exiting drivers' performance: lower traffic volume results in elevated exiting speed and deceleration, and diverging drivers begin to decelerate earlier along the main lane when traffic volume is low. However, speeds at the end of the deceleration lane and the site of lane changing are not significantly influenced by traffic volume.
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Benedetto A, Migliardo F, Magazù S. Protein Dynamics by Neutron Scattering: The Protein Dynamical Transition. Biophys J 2012. [DOI: 10.1016/j.bpj.2011.11.306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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50
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Magazù S, Migliardo F, Benedetto A. Elastic incoherent neutron scattering operating by varying instrumental energy resolution: principle, simulations, and experiments of the resolution elastic neutron scattering (RENS). THE REVIEW OF SCIENTIFIC INSTRUMENTS 2011; 82:105115. [PMID: 22047337 DOI: 10.1063/1.3641870] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The main aim of this paper is to present the scientific case of the resolution elastic neutron scattering (RENS) method that is based on the collection of elastic neutron scattering intensity as a function of the instrumental energy resolution and that is able to extract information on the system dynamical properties from an elastic signal. In this framework, it is shown that in the measured elastic scattering law, as a function of the instrumental energy resolution, an inflection point occurs when the instrumental energy resolution intersects the system relaxation time, and in an equivalent way, a transition in the temperature behavior of the measured elastic scattering law occurs when the characteristic system relaxation time crosses the instrumental energy resolution time. With regard to the latter, an operative protocol to determine the system characteristic time by different elastic incoherent neutron scattering (EINS) thermal scans at different instrumental energy resolutions is also proposed. The proposed method, hence, is not primarily addressed to collect the measured elastic scattering intensity with a great accuracy, but rather relies on determining an inflection point in the measured elastic scattering law versus instrumental energy resolution. The RENS method is tested both numerically and experimentally. As far as numerical simulations are concerned, a simple model system for which the temperature behavior of the relaxation time follows an Arrhenius law, while its scattering law follows a Gaussian behavior, is considered. It is shown that the system relaxation time used as an input for the simulations coincides with the one obtained by the RENS approach. Regarding the experimental findings, due to the fact that a neutron scattering spectrometer working following the RENS method has not been constructed yet, different EINS experiments with different instrumental energy resolutions were carried out on a complex model system, i.e., dry and D(2)O hydrated lysozyme, in an extended temperature range. The resulting temperature behavior of the system relaxation time, obtained with RENS method, agrees very well with the one obtained in literature, for the same system, following the quasi-elastic neutron scattering (QENS) approach. The proposed scientific case puts into evidence the challenges of an RENS spectrometer working by varying the instrumental energy resolution; in particular, in comparison with QENS, the proposed RENS method requires a smaller amount of sample, which is an important point in dealing with biological and exotic systems; it is not affected by the use of model functions for fitting spectra as in QENS, but furnishes a direct access to relevant information.
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