Publications by authors named "Geórgia Labuto"

13 Publications

  • Page 1 of 1

Spatio-temporal changes in water quality in the Guarapiranga reservoir (São Paulo, Brazil): insights from a long-term monitoring data series.

Environ Monit Assess 2021 Jun 3;193(7):380. Epub 2021 Jun 3.

Department of History, Georgetown University, 3700 O Street NW, Washington, DC, 20057, USA.

The provision of drinking water in metropolises is a challenge that requires programs for continuous monitoring of water quality and processes that impact the land cover of the watershed. In this work, we investigated through multivariate statistical analysis the temporal and spatial trends of several variables, not yet explored in a data series that includes 42 years (1978-2020) of monitoring in the hydrographic basin of the Guarapiranga reservoir, in the São Paulo Metropolitan Region-SPMR (Brazil). This reservoir is the source of drinking water for 3.8 million people and plays a strategic role in the social, environmental, and economic structure at SPMR. Our results point to the continuous degradation of water quality in the reservoir, although with different causes and spatio-temporal aspects. Between the 1970s and 1980s, variables associated with erosion/silting played a more critical role. From the 1990s, the introduction of N and P intensified, and the concentration of thermotolerant coliforms increased. The loss of quality is mainly associated with the progressive advance of urban settlements without planning combined with the inefficient initiatives to control domestic sewage pollution. If there is no rapid and comprehensive intervention, there is a risk that the Guarapiranga reservoir may become unsuitable for drinking water supply and other types of use in the future. This scenario will represent a critical obstacle to regional development and the quality of life of the population.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s10661-021-09167-yDOI Listing
June 2021

Textile effluent treatment employing yeast biomass and a new nanomagnetic biocomposite.

Environ Sci Pollut Res Int 2021 Jun 28;28(21):27318-27332. Epub 2021 Jan 28.

Laboratory of Integrated Sciences, Universidade Federal de São Paulo, Prof. Artur Riedel, 275 - Eldorado, Diadema, São Paulo, CEP: 09972-270, Brazil.

Fabric dyeing produces high amounts of wastewater containing organic and inorganic pollutants such as reactive dyes that are the most common textile dyes employed by the industry. Three vinylsulfonic reactive dyes, blue 19 (B-19), red 198 (R-198), and yellow 15 (Y-15), were removed from effluents of industrial-like dyeing processes employing three adsorbents: (1) magnetite nanoparticles (MNP), (2) yeast waste obtained after β-glucan removal from yeast biomass (YW), and (3) nanomagnetic composite produced from YW and MNP (YW-MNP). The non-linear kinetic pseudo-second-order and two-stage models best explained the experimental phenomena for the majority of adsorbate:adsorbent systems. The theoretical isotherm models were fitted to experimental isotherms obtained from experiments conducted with appropriated dilutions of effluents, which have a specific condition, limited by the maximum dye concentration established by the dye recipe. Thus, the saturation of adsorbents was not reached for all adsorbate:adsorbent systems. In this way, the best conditional sorption capacities (SC) were obtained by YW (1.7, 2.3, and 2.5 g/kg for B-19, R-198, and Y-15, respectively). The SIPS model best described all dyes adsorbed by YW, while the D-R model best described the phenomena for MNP and YW-MNP.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11356-021-12594-6DOI Listing
June 2021

Hexavalent chromium removal from water: adsorption properties of in natura and magnetic nanomodified sugarcane bagasse.

Environ Sci Pollut Res Int 2021 May 6;28(19):24816-24829. Epub 2021 Jan 6.

Laboratório de Materiais Poliméricos e Biossorventes, Universidade Federal de São Carlos, Araras, SP, 13600-970, Brazil.

Biosorption has become a viable and ecological process in which biological materials are employed as adsorbents for the removal of potentially toxic metals, such as hexavalent chromium, from aqueous matrices. This work proposed the use of in natura (SB) and nanomodified sugarcane bagasse (SB-NP) with ferromagnetic nanoparticles (FeO) to adsorb Cr(VI) from water. These materials were analyzed by X-ray Spectroscopy (XRD), Scanning Electron Microscopy (SEM), and Fourier Transform Infrared Spectroscopy (FTIR) to investigate their morphology and interaction with Cr(VI). It was observed the efficient impregnation of magnetite on the SB surface and the presence of functional groups such as O-H, C-H, C=O, C-O-C, C-O, and Fe-O (characteristic of magnetite). The best conditions for Cr(VI) removal in aqueous medium were determined by assessing the pH at the point of zero charge (pH = 6.1 and 5.8 for SB and SB-NP, respectively), adsorption pH and kinetics, and adsorption capacity. Batch procedures were performed using increasing concentrations of Cr(VI), 10-100 mg/L at pH 1.0, and 30 min of contact time. The adsorbent dose was 10 mg/L, and the experimental adsorption capacities (SC) for SB, NP, and SB-NP were 1.49 ± 0.06 mg/g, 2.48 ± 0.57 mg/g, and 1.60 ± 0.08 mg/g, respectively. All Cr contents were determined by flame atomic absorption spectrometry (FAAS). The pseudo-2nd-order kinetic equation provided the best adjustments with r 0.9966 and 0.9931 for SB and SB-NP, respectively. Six isotherm models (Langmuir, Freundlich, Sips, Temkin, Dubinin-Radushkevich, and Hill) were applied to the experimental data, and Freundlich, Dubinin-Radushkevich (D-R), and Temkin were the models that best described the experimental sorption process. The binding energy values (E) provided by the D-R model were 0.11 ± 0.25, 0.09 ± 0.20, and 0.08 ± 0.25 kJ/mol, for NP, SB-NP, and SB, respectively, and denote a physical interaction for the studied adsorbate-adsorbent system. The nanomodification of the biomass slightly improved the efficiency for the sorption of Cr(VI) and facilitated the removal of Cr(VI)-containing biosorbents from water medium.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11356-020-11726-8DOI Listing
May 2021

Pharmaceutical market, environmental public policies and water quality: the case of the São Paulo Metropolitan Region, Brazil.

Cad Saude Publica 2020 23;36(11):e00192319. Epub 2020 Nov 23.

Instituto de Ciências Ambientais, Químicas e Farmacêuticas, Universidade Federal de São Paulo, Diadema, Brasil.

Water pollution has been an increasing concern for the authorities responsible for planning and executing public policies. In this qualitative research, we have discussed the most sold pharmaceuticals in the São Paulo Metropolitan Region, Brazil, and compared public policies focused on pharmaceuticals and environmental issues among countries/regions. For that, data provided by Close-Up International related to the sales of medicines in the São Paulo Metropolitan Region between April/2016 and April/2017 were collected and processed to identify and quantify the pharmaceutical products. The 300 most sold medicines in the São Paulo Metropolitan Region fall in 26 therapeutic classes, which include 159 drugs. The most sold pharmaceutical products group is nonsteroidal anti-inflammatory drugs (NSAIDs) representing approximately 44.3% of the total. The ten most sold pharmaceuticals sum up 1200 tons. Dipyrone is the first place in mass representing around 488 tons, followed by metformin with around 310 tons commercialized. Public policies focused on pharmaceuticals in the environment still need adjustments to improve reinforcement, even in developed countries. There is no international standard on how to conduct the issue, each country adopting the public policy that best matches to the local. Brazil, despite having some legislation that approaches the theme, still lacks effective public policies and stakeholder awareness. In this aspect, the need for improvement of the reverse logistics system, consumer orientation to the adequate disposal of unused/expired medicines, and the adoption of the unit-dose system as a therapeutic strategy is evident.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1590/0102-311X00192319DOI Listing
March 2021

Nanomodified sugarcane bagasse biosorbent: synthesis, characterization, and application for Cu(II) removal from aqueous medium.

Environ Sci Pollut Res Int 2021 May 31;28(19):24744-24755. Epub 2020 Oct 31.

Laboratório de Materiais Poliméricos e Biossorventes, Universidade Federal de São Carlos, Araras, SP, 13600-970, Brazil.

Biosorption is a technique widely used in the remediation of contaminated effluents, and its main advantages are its easy applicability, high efficiency rate, versatility, and its economic viability. Associated with nanotechnology, this work proposes the use of nanocomposites of sugarcane bagasse (SB) and ferromagnetic nanoparticles (FeO) in the removal of metallic ions present in contaminated water. SB is a promising adsorbent material since it is an abundant agricultural residue, easily accessed. By using the coprecipitation method, two nanocomposites were obtained from in natura (SB-NP) or acid-treated (MSB-NP) sugarcane bagasse. These materials were synthetized by impregnation of FeO to gain paramagnetic properties and to facilitate the removal of the contaminant-containing adsorbent. The characterization of the nanocomposites was performed using pH, FTIR, XRD, and SEM/EDS techniques, to evaluate the synthesis efficiency and investigate the morphology of the materials. The efficiency of magnetite impregnation on the SB was assessed by SEM/EDS and XRD, while the main functional groups (carbonyl, carboxyl, hydroxyl, amine, amide, and nitrate) responsible for adsorption were found by FTIR. In the surface charge characterization by pH sorption of dyes, it was found that negative charges are predominant. The pH for SB-NP and MSB-NP was 5.95 and 5.59, respectively, and the chosen Cu(II) adsorption pH was 6.2 ± 0.1. The adsorption equilibrium was reached between 10 and 60 min of contact time. The maximum experimental sorption capacity (SC) was 2.53 ± 0.09 (SB-NP) and 2.61 ± 0.01 mg/g (MSB-NP). The isotherm models applied to the experimental data were Langmuir, Freundlich, Sips, Temkin, and Dubinin-Radushkevich, and Temkin best described the adsorption phenomena for Cu(II) by SB-NP (r = 0.9976 and χ = 3.965) and MSB-NP (r = 0.9990 and χ = 1.816). Reuse cycles of the nanocomposites were also performed employing ten cycles of sorption using 50 mg/L Cu(II) solutions, after which the materials showed SC = 7.47 ± 0.04 mg/g (SB-NP) and 7.82 ± 0.04 mg/g (MSB-NP). Therefore, the investigated materials exhibited promising results to be used as biosorbents in the remediation of effluents contaminated with toxic metal ions, such as copper.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11356-020-11345-3DOI Listing
May 2021

Microplastics in sediments from Amazon rivers, Brazil.

Sci Total Environ 2020 Dec 10;749:141604. Epub 2020 Aug 10.

Laboratory of Integrated Sciences (LabInSciences), Universidade Federal de São Paulo (Unifesp), Diadema, SP CEP 09972-270, Brazil; Department of Environmental Sciences, Universidade Federal de São Paulo (Unifesp), Diadema, SP CEP 09972-270, Brazil. Electronic address:

We assessed the concentrations of microplastics in sediment samples collected in seven sites from Solimões, Negro and Amazon rivers, upstream and downstream the metropolitan region of Manaus. Concentrations ranged from 417 to 8178 particles/kg of dried sediment (microplastics: 0.063-5 mm), and from 0 to 5725 particles/kg of dried sediment (microplastics: 0.063-1 mm). The highest microplastics concentrations were observed in samples from shallow water (water depth of 5-7 m) sites with lower water velocity of the Negro river surrounding Manaus, and the lowest concentration in farthest sample collected in deeper zone (water depth of 34 m) of the Amazon river around 110 km downstream Manaus. The variation of microplastics concentrations within the studied area can be related to hydraulic characteristics defining the erosive-depositional behavior of the sampling sites and their proximity to Manaus. Our results represent the first report to show the ubiquitous presence and widespread distribution of microplastics in sediments from the lower Solimões, lower Negro and upper Amazon rivers.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.scitotenv.2020.141604DOI Listing
December 2020

Activated carbon production from industrial yeast residue to boost up circular bioeconomy.

Environ Sci Pollut Res Int 2021 May 15;28(19):24694-24705. Epub 2020 Aug 15.

Department of Chemistry, Universidade Federal de São Paulo, Diadema, SP, 09913-030, Brazil.

This work aims to obtain activated carbon (AC) from yeast residue to boost up bioeconomy. In this way, carbon was prepared from yeast biomass produced by the ethanol industry and after beta-glucan extraction. Carbon was activated with CO, water vapor, and a combination of both using an experimental design. The best conditions to produce AC were activation with CO for 30 min at 850 °C and CO flow of 0.09 L/min, set by experimental design and desirability function to optimize the yield, surface area, and microporosity. Thus, for physical activation with water vapor employing the optimized conditions, it was possible to achieve a yield of 56.6% (m/m) for AC with 1144 m/g of surface area and mean micropore volume of 0.53 cm/g. The maximum AC surface area reached 1616 ± 567 m/g with a yield of 21 ± 1%. The prepared ACs were characterized by elemental analysis, X-ray diffractometry, infrared spectroscopy, thermogravimetry analysis, pH, and potentiometric titration to determine the main functional groups of sorption sites. The carbon obtained from the desirability condition was used to remove dipyrone from synthetic aqueous effluent with an experimental sorption capacity of 88 ± 4 mg/g, being the phenomenon described by the Freundlich isotherm model.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11356-020-10458-zDOI Listing
May 2021

Environmentally friendly synthesis of [email protected] nanocomposite: characterization and application as an adsorbent to aniline removal from aqueous solution.

Environ Sci Pollut Res Int 2020 Mar 8;27(9):9181-9191. Epub 2020 Jan 8.

Department of Chemistry, Universidade Federal de São Paulo, São Paulo, Brazil.

Silica-based nanocomposite syntheses employ many harmful substances, which, in turn, demand the development of new synthetic environmental-friendly routes that meet the principles of green chemistry. In this work, we present a novel magnetic adsorbent, [email protected] nanocomposite ([email protected]), successfully obtained without surfactant, employing an electrochemical method. We characterized the nanocomposite and then applied it to remove aniline from the water medium. Characterization was carried out by vibrating-sample magnetometry (VSM), X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FT-IR). The parameters to the adsorptive removal of aniline were successfully optimized, which made possible to remove 71.04 ± 0.06% (126.6 ± 2.0 mg/g) from a 100 mg/L aniline solution at pH 6 and 323 K, by employing around 50 mg of [email protected], at a contact time of 40 min. The adsorption of aniline by [email protected] is a spontaneous and exothermic process according to the pseudo-second-order kinetic model (r = 1 at 20 mg/L aniline concentration) and the Freundlich isotherm model (r = 0.9986).
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11356-019-07491-yDOI Listing
March 2020

Biosorption of 17α-ethinylestradiol by yeast biomass from ethanol industry in the presence of estrone.

Environ Sci Pollut Res Int 2019 Oct 26;26(28):28419-28428. Epub 2019 Apr 26.

Departamento de Química, Universidade Federal de São Paulo, Diadema, Rua São Nicolau, 210-Centro, Diadema, SP, CEP 09913-030, Brazil.

Yeast biomass from ethanol industry (YB) was evaluated as a biosorbent to 17α-ethinylestradiol (EE) alone and along with estrone (EST). This material is rich in sorption sites and has a good cost-benefit ratio, since it is an industrial residue largely produced (around 30 g for each liter of ethanol). A 2-factorial design was carried out to evaluate the sorption capacity of YB for EE considering the variables pH, biosorbent dose (BD), and ionic strength (IS), at two hormone concentration (HC) levels. The best conditions assessed for individual EE adsorption (pH = 10, IS = 0.1 mol/L, and BD = 0.5 mg/L) were also established for adsorption carried out in the presence of EST. Individuals EE and EST experimental sorption capacities (SC) were, respectively, 24.50 ± 0.07 and 0.80 ± 0.07 mg/g, fairly similar to Q (EE, 21.41 ± 1.27 mg/g; EST, 0.93 ± 0.075 mg/g) from Langmuir model. The Freundlich model best fitted the experimental data for EE adsorption (r = 0.9925; χ = 0.5575). The study carried out in the presence of EST showed an associative/competitive sorption process between EE and EST, which may be explained by their similar chemical structures and organic carbon-water partition coefficients K.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11356-019-05202-1DOI Listing
October 2019

Oil spill cleanup employing magnetite nanoparticles and yeast-based magnetic bionanocomposite.

J Environ Manage 2019 Jan 5;230:405-412. Epub 2018 Oct 5.

Departamento de Química, Universidade Federal de São Paulo, Diadema, Rua São Nicolau, 210 - Centro, CEP 09913-030, Diadema, SP, Brazil. Electronic address:

Oil spill is a serious environmental concern, and alternatives to remove oils from water involving biosorbents associated to nanoparticles is an emerging subject. Magnetite nanoparticles (MNP) and yeast magnetic bionanocomposite (YB-MNP) composed by yeast biomass from the ethanol industry were produced, characterized, and tested to remove new motor oil (NMO), mixed used motor oil (MUMO) and Petroleum 28 °API (P28API) from water following the ASTM F726-12 method, which was adapted by insertion of a lyophilization step to ensure the accuracy of the gravimetric approach. Temperature, contact time, the type and the amount of the magnetic material were the parameters evaluated employing a fractional factorial design. It was observed the removal of 89.0 ± 2.6% or 3522 ± 118 g/kg (NMO) employing MNP; 69.1 ± 6.2% or 2841 ± 280 g/kg (MUMO) with YB-MNP; and 55.3 ± 8.2% or 2157 ± 281 g/kg (P28API) using MNP. The temperature was the most significant parameter in accordance with the Pareto's graphics (95% confidence) for all oil samples considered in this study as well as the two magnetic materials. Contact time and the interaction between the materials and temperature were also relevant. The D-Optimals designs showed that the NMO and P28API responded in a similar way for all evaluated parameters, while the uptake of MUMO was favored at higher temperatures. These behaviors demonstrate the influence of oil characteristics and the intermolecular forces between the oil molecules on the mechanism dragging process performed by the attraction between magnetite nanoparticles and a 0.7 T magnet. It was clear that this kind of experiment is predominantly a physic phenomenon which cannot be described as adsorption process.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jenvman.2018.09.094DOI Listing
January 2019

Agricultural solid waste for sorption of metal ions, part II: competitive assessment in multielemental solution and lake water.

Environ Sci Pollut Res Int 2018 Dec 20;25(36):35906-35914. Epub 2018 Mar 20.

Laboratório de Materiais Poliméricos e Biossorventes, Universidade Federal de São Carlos, Araras, SP, 13600-970, Brazil.

Sugarcane bagasse and hydroponic lettuce roots were used as biosorbents for the removal of Cu(II), Fe(II), Mn(II), and Zn(II) from multielemental solutions and lake water, in batch processes. These biomasses were studied in natura (lettuce roots, NLR, and sugarcane bagasse, NSB) and chemically modified with HNO (lettuce roots, MLR, and sugarcane bagasse, MSB). The results showed higher adsorption efficiency for MSB and either NLR or MLR. The maximum adsorption capacities (q) in multielemental solution for Cu(II), Fe(II), Mn(II), and Zn(II) were 35.86, 31.42, 3.33, and 24.07 mg/g for NLR; 25.36, 27.95, 14.06, and 6.43 mg/g for MLR; 0.92, 3.94, 0.03, and 0.18 mg/g for NSB; and 54.11, 6.52, 16.7, and 1.26 mg/g for MSB, respectively. The kinetic studies with chemically modified biomasses indicated that sorption was achieved in the first 5 min and reached equilibrium around 30 min. Sorption of Cu(II), Fe(II), Mn(II), and Zn(II) in lake water by chemically modified biomasses was 24.31, 14.50, 8.03, and 8.21 mg/g by MLR, and 13.15, 10.50, 6.10, and 5.14 mg/g by MSB, respectively. These biosorbents are promising and low costs agricultural residues, and as for lettuce roots, these showed great potential even with no chemical modification.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11356-018-1726-7DOI Listing
December 2018

Agricultural solid waste for sorption of metal ions: part I-characterization and use of lettuce roots and sugarcane bagasse for Cu(II), Fe(II), Zn(II), and Mn(II) sorption from aqueous medium.

Environ Sci Pollut Res Int 2018 Dec 8;25(36):35895-35905. Epub 2018 Mar 8.

Laboratório de Materiais Poliméricos e Biossorventes, Universidade Federal de São Carlos, Araras, SP, 13600-970, Brazil.

Sugarcane bagasse and hydroponic lettuce roots were used as biosorbents for Cu(II), Fe(II), Zn(II), and Mn(II) removal from monoelemental solutions in aqueous medium, at pH 5.5, using batch procedures. These biomasses were studied in natura (lettuce roots, NLR, and sugarcane bagasse, NSB) and modified with HNO (lettuce roots, MLR, and sugarcane bagasse, MSB). Langmuir, Freundlich, and Dubinin-Radushkevich non-linear isotherm models were used to evaluate the data from the metal ion adsorption assessment. The maximum adsorption capacities (q) in monoelemental solution, calculated using the Langmuir isothermal model for Cu(II), Fe(II), Zn(II), and Mn(II), were respectively 24.61, 2.64, 23.04, and 5.92 mg/g for NLR; 2.29, 16.89, 1.97, and 2.88 mg/g for MLR; 0.81, 0.06, 0.83, and 0.46 mg/g for NSB; and 1.35, 2.89, 20.76, and 1.56 mg/g for MSB. The Freundlich n parameter indicated that the adsorption process was favorable for Cu(II) uptake by NLR; Fe(II) retention by MLR and MSB; and Zn(II) sorption by NSB, MLR, and NSB and favorable for all biomasses in the accumulation of Mn(II). The Dubinin-Radushkevich isotherm was applied to estimate the energy (E) and type of adsorption process involved, which was found to be a physical one between analytes and adsorbents. Organic groups such as O-H, C-O-C, CH, and C=O were found in the characterization of the biomass by FTIR. In the determination of the biomass surface charges by using blue methylene and red amaranth dyes, there was a predominance of negative charges.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11356-018-1615-0DOI Listing
December 2018

Effect of root age on the allocation of metals, amino acids and sugars in different cell fractions of the perennial grass Paspalum notatum (bahiagrass).

Plant Physiol Biochem 2011 Dec 28;49(12):1442-7. Epub 2011 Sep 28.

Centro de Ecologia Funcional, Departamento de Ciências da Vida, Faculdade de Ciências e Tecnologia, Universidade de Coimbra, Apartado 3046, 3001-401 Coimbra, Portugal.

This work aimed to compare the allocation of Al, Fe, Cu, Ni, amino acids and sugars in different fractions of root cells of Paspalum notatum with 21 and 120 days old grown in quartz sand. In general younger roots showed a higher content of Al, Fe, Cu Ni, amino acids and sugars, compared to older roots. This can be due to a higher metabolic activity of younger roots and/or to structural changes that can occur with cell ageing. Al and Fe were mainly allocated to fractions with pectin, hemicellulose and cellulose, both in younger and older roots. However, older roots also showed a significant fraction of Al allocated to the intracellular fraction. It seems that older roots were less able to prevent the entry of Al in the cytoplasm. The proportion of Cu was higher in intracellular components, both in younger and older roots, as expected from an essential nutrient. Ni content was very low in older roots and in younger roots it was mainly allocated to the intracellular fraction and to the cell wall polysaccharides fraction. The amino acids were mainly allocated to the cytoplasm and polysaccharide fraction. Although younger roots showed a higher total amount of amino acids compared to older roots, the amino acids profile and allocation, mainly in the cytoplasm polysaccharides, was quite similar. Arabinose, a major component of structural glycoproteins of the primary cell wall matrix, was only detected in younger roots. Thus, it seems that root cells of P. notatum suffered changes in the composition of the cell wall components with ageing. To further understand the structural changes of root cells with ageing and its effect on metal allocation, it is important to quantify several components of the cell wall matrix, namely pectins and glycoproteins.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.plaphy.2011.09.010DOI Listing
December 2011
-->