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  Research Article  Application of Neutron Activation Analysis forDetermination of As, Cr, Hg, and Se in Mosses in theMetropolitan Area of the Valley of Toluca, Mexico R. Mejía-Cuero, 1,2 G. García-Rosales, 2 L. C. Longoria-Gándara, 1,3 M. C. López-Reyes, 1 and P. Ávila-Pérez  1,2 󰀱 National Institute for Nuclear Research, Carretera M ´exico-oluca S/N, La Marquesa, 󰀵󰀲󰀷󰀵󰀰 Ocoyoacac, MEX, Mexico 󰀲 Departamento de Posgrado, Instituto ecnol ´ogico de oluca, Ex-Rancho la Virgen S/N, 󰀵󰀰󰀱󰀲󰀰 Metepec, MEX, Mexico 󰀳 Division for Latin America, Department of echnical Cooperation, International Atomic Energy Agency, Wagramer Strasse 󰀵,P.O. Box 󰀱󰀰󰀰, 󰀱󰀴󰀰󰀰 Vienna, Austria Correspondence should be addressed to G. Garc´ıa-Rosales; ggarciarosales󰀵󰀰󰀸@gmail.comReceived 󰀱󰀲 December 󰀲󰀰󰀱󰀴; Revised 󰀲󰀶 March 󰀲󰀰󰀱󰀵; Accepted 󰀲󰀳 April 󰀲󰀰󰀱󰀵Academic Editor: Qiang JinCopyright © 󰀲󰀰󰀱󰀵 R. Mej´ıa-Cuero et al.TisisanopenaccessarticledistributedundertheCreativeCommonsAttributionLicense,which permits unrestricted use, distribution, and reproduction in any medium, provided the srcinal work is properly cited.Tis research presents a study o environmental monitoring at different sampling sites rom the Metropolitan Area o the Valley o oluca (MAV), Mexico, using mosses ( Leskea angustata  (ayl.) and  Fabronia ciliaris  (Brid.)) and soil samples. Te epiphyticmossesandsoilsweresampledintwocampaignswithintwoperiodsotheyear,arainyanddry-coldseason.Teselectedsamplingsites included urban regions (UR), transitional regions (R), and protected natural areas (PA). Te samples were analyzed by theInstrumental Neutron Activation Analysis (INAA) to determine As, Cr, Hg, and Se principally. However, due to the versatility o the analytic technique used, other elements including Cs, Co, Sc, Sb, Rb, Ce, La, Eu, and Yb were also detected. Statistical analysis(As, Cr, Hg, and Se) was carried out with principal components and cluster analysis methods; this revealed that a good correlationexists between metal content in mosses and the degree o pollution in the areas sampled. Te obtained results in mosses showedthat the concentrations o As, Cr, Co, Cs, Rb, Ce, La, and Yb increased with respect to the concentrations obtained during the󿬁rst sampling, whereas Se, Sc, Sb and Eu, concentrations were decreased. For As and Hg, the concentrations were similar in bothsampling periods. Te soil samples present the most signi󿬁cant concentration. 1. Introduction Te Metropolitan Area o the Valley o oluca (MAV) islocated in the central area o the State o Mexico and iscomprisedosevenmunicipalitieswithapopulationoabout󰀱.󰀸million.ItisthemostindustrializedregionoMexicowithdifferent areas o industry (tanneries, electroplating, textile,and kraf pulp bleaching) and also the signi󿬁cant amounto traffic [󰀱], resulting in the emission o various pollutantsintotheatmosphere.Currentlythedepositionlevelsometalsincluding As, Cr, Hg, and Se rom the atmosphere to thebiosphere may be signi󿬁cantly increased as a result o theanthropogenic input o ossil uels, dust rom agriculture,industry and metallurgy, or natural sources. Due to thediversity o their habitats, their structural simplicity, andrapid rate o multiplication, some mosses may be useultools or prospective studies to determine environmentalconditions and are ideal organisms or studying depositiono pollutants rom the atmosphere to vegetation [󰀲]. Mossesare ound in many different environments and consideredas indicators o elemental pollution [󰀳]. Several previousstudies have used plants and mosses as biomonitors becausethey acilitate the measurement o pollutant deposition [󰀴].Te diversity o mosses depends on the weather and sub-strate where they develop [󰀵] and the actors limiting theirdistribution are essentially water, temperature, and altitude.Te concentration o metals and other elements in mossesmay depend on morphological eatures [󰀶], wind direction,topography, altitude, latitude, and time o exposure. Addi-tionally, topsoil analysis has been widely used to evaluate Hindawi Publishing CorporationJournal of Chemistry Volume 2015, Article ID 278326, 13 pageshttp://dx.doi.org/10.1155/2015/278326  󰀲 Journal o Chemistry the uptake o contaminants in ecosystems, to estimate themaximum concentration o metal and other elements, and toevaluate their importance as a source o the metals and otherelements absorbed by mosses [󰀷]. Te organic raction o thetopsoil, in particular, the humus, can be used or measuringatmospheric deposition o metals and other elements [󰀸].In this context, the aim o this research is to determine theconcentrations o As, Cr, Hg, and Se in mosses and topsoilrom 󰀱󰀶 sampling sites in MAV using INAA. Te advantageo using INAA is the minimal sample preparation neededor analysis compared to methods and its multielement thatcan be nondestructive, with adequate limits o detection orthe majority o metals and other elements o environmentalinterest [󰀹]. 2. Material and Methods 󰀲.󰀱. Sampling.  First o all, the sampling sites were careully inspectedtodeterminethemossspeciespresentateachsite(󰀷different moss species were identi󿬁ed). However, not all wereound in all the sites investigated due to the characteristicso each area. Consequently, the main two dominant specieso epiphytic mosses were  Fabronia ciliaris  (Brid.) and  Leskeaangustata  (ayl.); these were collected in two samplingcampaigns rom the urban region (UR), transitional region(R), and the protected natural area (PA). Te 󿬁rst samplingwas perormed in November 󰀲󰀰󰀱󰀰 (dry season, autumn) andthesecondinAugust󰀲󰀰󰀱󰀱(rainyseason,summer);eachothesampling sites was selected afer considering the prevailingwinds,theproximityothesitecomparedtoareaswithhigherpopulation density, vehicular traffic, industrial activity, andthe availability o mosses.en grams o epiphytic mosses was collected rom six toten trees in a height greater than one meter. Moss sampleswereremovedromthetreeusingaplasticspatulaandplacedin polythene bags or transport to the laboratory. Duringsampling, observations o habitat type and relative density o moss carpets were perormed.Forthe󿬁rstsampling,sevensamplingpointswerelocatedin parks in urban regions (UR) (sites 󰀱–󰀷 were identi󿬁edas Negrete, Alameda, Reorma, H´ıpico, Pilita, Sant´ın, and olloc´an), two sampling points (sites 󰀸 and 󰀱󰀱, identi󿬁ed asLomas and San Miguel) were located in transition regions(R), and three sampling sites were located within naturalareas (PA) (sites 󰀱󰀳, 󰀱󰀵, and 󰀱󰀶, identi󿬁ed as San Anto-nio, Cacalomac´an, and Ciervita) (Figure 󰀱). For the second sampling, our sampling points were added to expand themonitoredarea:threeweresituatedintransitionregions(R)(sites 󰀹, 󰀱󰀰, and 󰀱󰀲, identi󿬁ed as Acazulco, Pedregal, andAmeyalco)andonewassituatedinanaturalarea(PA)(site󰀱󰀴,identi󿬁ed as San Diego). Te topsoil samples were collectedrom the same locations according to previously publishedmethodology [󰀱󰀰]. 󰀲.󰀲. Sample Preparation.  In the laboratory the mosses wereplaced in trays and dried at room temperature via exposureto sunlight or 󰀵 to 󰀸 days. Ten, the samples were groundwith an agate mortar and pestle to obtain a particle size o 󰀰.󰀸󰀵mm, and the product was stored in labeled polyethylenebottles (high density). Te collected topsoil samples werecleanedromextraneousplantmaterialsanddriedatambientroomtemperature,sortedtoremovegravel,andthenhomog-enizedandpassedthroughastainless-steelsieveo󰀰.󰀰󰀷󰀵mmaperture. Te resultant samples were stored in polyethylenebottles (high density). 󰀲.󰀳. Chemical Composition.  Te INAA was carried out atthe Department o Reactor, Neutron Activation AnalysisLaboratory, National Institute o Nuclear Research in Mexico(ININ). INAA was conducted using the standard method o analytical procedures and employed, described in detail by ravesi, 󰀱󰀹󰀷󰀵 [󰀱󰀱].o provide quality control, contents o elements yieldingshort- and long-lived isotopes were determined using certi-󿬁ed standard reerence materials (SRM). For analysis o themoss samples, standards were used: Lichen-󰀳󰀳󰀶 rom IAEA(International Atomic Energy Agency), Citrus Leaves SRM-󰀱󰀵󰀷󰀲 rom the US NIS (National Institute o Standards andechnology), and the SRM or topsoil Soil-󰀷 rom IAEA andSRM-󰀲󰀷󰀱󰀱 Montana II Soil rom US NIS or the measuredelements;thosereerencematerialswereanalyzedintriplicatealongwiththesurveyomossandtopsoilsamples.Teresultsor the SRM were within 󰀹󰀰–󰀱󰀰󰀵% o certi󿬁ed values; 󰀴󰀰mgo moss, topsoil, and control was added to quartz ampouleso 󰀹mm in diameter and 󰀶cm o length. SRM and sampleswere irradiated at the RIGA-MARK III nuclear researchreactor at the ININ in Mexico, using a neutron 󿬂ux density o   0.9 × 10 13 ncm −2 s −1 or 󰀲󰀰 hours in a SIFCA position.Afer irradiation, the samples were repacked and mea-sured afer 󰀶 days or 󰀳󰀰 minutes to determine  76 As,  140 La, 175 Yb, and  177 Lu, secondly they were measured afer 󰀳󰀰 daysor󰀳hoursto determine 203 Hg,  141 Ce,  60 Co, 51 Cr, 86 Rb, 124 Sb,and  46 Sc, and 󿬁nally they were measured between 󰀸󰀰 and 󰀱󰀶󰀰days or 󰀱󰀰–󰀱󰀶 hours to determine  75 Se,  152 Eu, and  134 Cs. Tegamma spectra o the samples were measured with a gammaspectrometer with a HPGe detector at a resolution (FWHM)o 󰀱.󰀹keV and or the peak at 󰀱󰀳󰀳󰀲keV corresponding to 60 Co. A multichannel analyzer, the 󰀸󰀱󰀹󰀲 OREC, operatedwith a peak determination program which was used oranalysis. Data processing was perormed using the sofwaredeveloped in ININ and Hypermet-PC. Te element contentswere determined on the basis o SRM and 󿬂ux comparators[󰀱󰀲, 󰀱󰀳]. 󰀲.󰀴. Statistical Analysis.  Te correlations between the sam-pling sites and metal concentration (or Hg, Se, Cr, and As)inmossesandtopsoilsweredeterminedviastatisticalanalysiswiththeStatistics󰀷.󰀰inormaticprogram[󰀱󰀴],usingprincipalcomponent analysis (PCA) with the cluster option (CA). 3. Results and Discussion 󰀳.󰀱. Chemical Composition Analysis in Moss Samples.  Teresults obtained or the 󿬁rst sampling are summarized inable 󰀱, where it is observed that the presence o As, Cr, Hg,and Se was due to the sensitivity o the analysis technique  Journal o Chemistry 󰀳 Symbology Natural protected areasArea of study Municipal limitWinds in summerWinds in winterPoints of samplingUrbanPoints1234567891011121314151620 0 20(km)Altitude2685266226442668262325962589267627402579268327652705310027443317TransitionNatural   NSW E F󰁩󰁧󰁵󰁲󰁥 󰀱: Sampling sites, wind directions, and altitudes in the MAV. used. Other elements such as Co, Cs, Sc, Sb, Rb, Ce, La, Eu,and Yb were also detected. It is important to consider thatsome o these elements can be present in the plant’s tissues asa component o irregularly shaped particles adsorbed to theplant surace.Te results obtained indicate the relative concentrationsas Co  >  Cr  >  Rb  >  Ce  >  La  >  Sc  >  As  >  Sb  >  Se  >  Cs  >  Yb  > Hg  >  Eu. Te sites with the highest elemental concentrationsare located in UR and R and they do not demonstratea trend. Tis behavior can perhaps be attributed to thegeographical site location (topography) and characteristicso each sampling site. Te presence o some elements in thesamples may be due to natural, local, or secondary sources.Te highest concentrations o As were ound in Reormaand olloc´an located in the center o MAV correspondingto UR and San Antonio located in PA. Arsenic is widely distributed in soils, water, and air. It is a component o more than 󰀱󰀰󰀰 different minerals. Teir speciation o theelement is a key actor in controlling mobility, availability,andtoxicityinnaturalenvironments.Arsenicoccurrenceandmobilization take place through a combination o naturalprocesses, or example, through water reactions, biologicalactivity, and volcanic emissions. Anthropogenic activitiesaccountorwidespreadAscontaminationarisingromavari-etyoindustrialprocessessuchaswoodpreservatives,paints,alloys, semiconductors, ossil uel combustion, mine wastes,smelting, land󿬁lling, sewerage, and agricultural applications(pesticides and ertilizer) which may also introduce As intothe environment [󰀱󰀵].Te sites with the high concentrations o Cr are commoninAlameda,olloc´an,H´ıpico,andNegrete,whicharelocated  󰀴 Journal o Chemistry      T   󰁡   󰁢   󰁬   󰁥    󰀱   :    E     l   e   m   e   n    t   c   o   n   c   e   n    t   r   a    t    i   o   n     (   m   g     k   g   −     󰀱  )    i   n   m   o   s   s     f   r   o   m    t     h   e     󿬁   r   s    t   s   a   m   p     l    i   n   g .     S   a   m   p     l    i   n   g   s    i    t   e   s    A   s    C   r    H   g    S   e    C   o    C   s    S   c    S     b    R     b    C   e    E   u    L   a    Y     b    N   e   g   r   e    t   e     (    U    R     )    󰀲 .    󰀱    󰀲     ±     󰀰 .    󰀱    󰀶    󰀴    󰀰 .    󰀷    󰀰     ±     󰀲 .    󰀶    󰀸    󰀰 .    󰀲    󰀱     ±     󰀰 .    󰀰    󰀶    󰀱 .    󰀵    󰀲     ±     󰀰 .    󰀲    󰀸    󰀲 .    󰀶    󰀶     ±     󰀰 .    󰀱    󰀵    󰀱 .    󰀴    󰀳     ±     󰀰 .    󰀱    󰀷     ∗     󰀴 .    󰀰    󰀸     ±     󰀰 .    󰀱    󰀶    󰀱 .    󰀱    󰀰     ±     󰀰 .    󰀲    󰀲    󰀲    󰀶 .    󰀵    󰀰     ±     󰀱 .    󰀴    󰀱    󰀵 .    󰀶    󰀱     ±     󰀰 .    󰀵    󰀸    󰀰 .    󰀴    󰀰    󰀰     ±     󰀰 .    󰀱    󰀱     ∗     󰀳 .    󰀴    󰀳     ±     󰀰 .    󰀱    󰀲    󰀰 .    󰀱    󰀷     ±     󰀰 .    󰀰    󰀴    A     l   a   m   e     d   a     (    U    R     )    󰀲 .    󰀴    󰀳     ±     󰀰 .    󰀱    󰀶    󰀵    󰀱 .    󰀰    󰀹     ±     󰀳 .    󰀳    󰀷     ∗     󰀰 .    󰀲    󰀷     ±     󰀰 .    󰀰    󰀷    󰀱 .    󰀸    󰀰     ±     󰀰 .    󰀳    󰀴     ∗     󰀲 .    󰀵    󰀵     ±     󰀰 .    󰀱    󰀴    󰀱 .    󰀲    󰀳     ±     󰀰 .    󰀱    󰀵    󰀴 .    󰀲    󰀹     ±     󰀰 .    󰀱    󰀶    󰀲 .    󰀹    󰀲     ±     󰀰 .    󰀵    󰀹     ∗     󰀲    󰀳 .    󰀷    󰀵     ±     󰀱 .    󰀳    󰀴    󰀷 .    󰀰    󰀴     ±     󰀱 .    󰀲    󰀰    󰀰 .    󰀴    󰀰    󰀲     ±     󰀰 .    󰀱    󰀱     ∗     󰀴 .    󰀳    󰀰     ±     󰀰 .    󰀱    󰀵    󰀰 .    󰀵    󰀰     ±     󰀰 .    󰀱    󰀱    R   e     f   o   r   m   a     (    U    R     )    󰀳 .    󰀶    󰀹     ±     󰀰 .    󰀳    󰀰    󰀳    󰀹 .    󰀵    󰀴     ±     󰀳 .    󰀱    󰀴    󰀰 .    󰀳    󰀶     ±     󰀰 .    󰀰    󰀹    󰀰 .    󰀸    󰀶     ±     󰀰 .    󰀱    󰀷    󰀲 .    󰀰    󰀱     ±     󰀰 .    󰀱    󰀰    󰀰 .    󰀶    󰀷     ±     󰀰 .    󰀱    󰀱    󰀲 .    󰀳    󰀲     ±     󰀰 .    󰀰    󰀹    󰀰 .    󰀶    󰀷     ±     󰀰 .    󰀱    󰀱    󰀱    󰀴 .    󰀶    󰀱     ±     󰀱 .    󰀴    󰀵    󰀴 .    󰀶    󰀹     ±     󰀰 .    󰀴    󰀵    󰀰 .    󰀲    󰀴     ±     󰀰 .    󰀰    󰀷    󰀲 .    󰀷    󰀱     ±     󰀰 .    󰀰    󰀹    󰀰 .    󰀱    󰀴     ±     󰀰 .    󰀰    󰀳    H    ´   ı   p    i   c   o     (    U    R     )    󰀱 .    󰀷    󰀷     ±     󰀰 .    󰀱    󰀳    󰀴    󰀳 .    󰀳    󰀳     ±     󰀲 .    󰀸    󰀲    󰀰 .    󰀲    󰀸     ±     󰀰 .    󰀰    󰀷    󰀱 .    󰀳    󰀴     ±     󰀰 .    󰀲    󰀵    󰀱 .    󰀷    󰀴     ±     󰀰 .    󰀰    󰀹    󰀰 .    󰀷    󰀲     ±     󰀰 .    󰀰    󰀹    󰀲 .    󰀶    󰀰     ±     󰀰 .    󰀱    󰀰    󰀲 .    󰀲    󰀷     ±     󰀰 .    󰀴    󰀶    󰀱    󰀹 .    󰀷    󰀴     ±     󰀱 .    󰀱    󰀵    󰀴 .    󰀳    󰀳     ±     󰀰 .    󰀵    󰀴    󰀰 .    󰀱    󰀵     ±     󰀰 .    󰀰    󰀵    󰀲 .    󰀴    󰀰     ±     󰀰 .    󰀰    󰀹    󰀰 .    󰀱    󰀲     ±     󰀰 .    󰀰    󰀳    P    i     l    i    t   a     (    U    R     )    󰀲 .    󰀲    󰀵     ±     󰀰 .    󰀱    󰀲    󰀲    󰀸 .    󰀲    󰀶     ±     󰀱 .    󰀷    󰀸    󰀰 .    󰀴    󰀴     ±     󰀰 .    󰀰    󰀸     ∗     󰀱 .    󰀳    󰀸     ±     󰀰 .    󰀱    󰀵    󰀲 .    󰀳    󰀰     ±     󰀰 .    󰀱    󰀲    󰀰 .    󰀸    󰀶     ±     󰀰 .    󰀱    󰀱    󰀲 .    󰀹    󰀶     ±     󰀰 .    󰀱    󰀲    󰀱 .    󰀰    󰀰     ±     󰀰 .    󰀱    󰀳    󰀲    󰀷 .    󰀳    󰀸     ±     󰀲 .    󰀰    󰀳    󰀱    󰀰 .    󰀳    󰀱     ±     󰀰 .    󰀸    󰀵    󰀰 .    󰀲    󰀲     ±     󰀰 .    󰀰    󰀶    󰀶 .    󰀲    󰀰     ±     󰀰 .    󰀲    󰀲    󰀰 .    󰀴    󰀶     ±     󰀰 .    󰀱    󰀱    S   a   n    t    ´   ı   n     (    U    R     )    󰀱 .    󰀵    󰀲     ±     󰀰 .    󰀱    󰀲    󰀲    󰀸 .    󰀳    󰀵     ±     󰀱 .    󰀷    󰀷    󰀰 .    󰀲    󰀷     ±     󰀰 .    󰀰    󰀹    󰀱 .    󰀳    󰀳     ±     󰀰 .    󰀱    󰀶    󰀴 .    󰀵    󰀰     ±     󰀰 .    󰀲    󰀲    󰀱 .    󰀱    󰀸     ±     󰀰 .    󰀱    󰀳    󰀴 .    󰀹    󰀰     ±     󰀰 .    󰀲    󰀰     ∗     󰀰 .    󰀷    󰀷     ±     󰀰 .    󰀱    󰀰    󰀴    󰀱 .    󰀶    󰀰     ±     󰀲 .    󰀹    󰀰     ∗     󰀱    󰀳 .    󰀸    󰀵     ±     󰀱 .    󰀱    󰀳     ∗     󰀰 .    󰀲    󰀹     ±     󰀰 .    󰀰    󰀸    󰀸 .    󰀰    󰀷     ±     󰀰 .    󰀲    󰀶     ∗     󰀰 .    󰀶    󰀹     ±     󰀰 .    󰀱    󰀷     ∗     T   o     l     l   o   c    ´   a   n     (    U    R     )    󰀴 .    󰀸    󰀷     ±     󰀰 .    󰀴    󰀰     ∗     󰀴    󰀳 .    󰀹    󰀷     ±     󰀳 .    󰀵    󰀰    󰀰 .    󰀳    󰀲     ±     󰀰 .    󰀰    󰀸    󰀱 .    󰀰    󰀶     ±     󰀰 .    󰀲    󰀱    󰀲 .    󰀷    󰀸     ±     󰀰 .    󰀱    󰀴    󰀰 .    󰀹    󰀱     ±     󰀰 .    󰀱    󰀴    󰀳 .    󰀴    󰀵     ±     󰀰 .    󰀱    󰀴    󰀰 .    󰀸    󰀴     ±     󰀰 .    󰀱    󰀴    󰀱    󰀸 .    󰀸    󰀱     ±     󰀱 .    󰀸    󰀴    󰀷 .    󰀰    󰀱     ±     󰀰 .    󰀶    󰀷    󰀰 .    󰀳    󰀹     ±     󰀰 .    󰀱    󰀱    󰀳 .    󰀶    󰀵     ±     󰀰 .    󰀱    󰀴    󰀰 .    󰀲    󰀰     ±     󰀰 .    󰀰    󰀵    L   o   m   a   s     (    T    R     )    󰀱 .    󰀰    󰀷     ±     󰀰 .    󰀰    󰀷    󰀱    󰀳 .    󰀳    󰀸     ±     󰀰 .    󰀸    󰀲    󰀰 .    󰀱    󰀳     ±     󰀰 .    󰀰    󰀳    󰀰 .    󰀸    󰀵     ±     󰀰 .    󰀱    󰀳    󰀱 .    󰀰    󰀹     ±     󰀰 .    󰀰    󰀶    󰀰 .    󰀲    󰀹     ±     󰀰 .    󰀰    󰀵    󰀱 .    󰀱    󰀶     ±     󰀰 .    󰀰    󰀴    󰀰 .    󰀵    󰀳     ±     󰀰 .    󰀱    󰀰    󰀸 .    󰀴    󰀹     ±     󰀰 .    󰀷    󰀵    󰀲 .    󰀰    󰀳     ±     󰀰 .    󰀲    󰀴    󰀰 .    󰀱    󰀱     ±     󰀰 .    󰀰    󰀲    󰀹    󰀱 .    󰀳    󰀲     ±     󰀰 .    󰀰    󰀵    󰀰 .    󰀰    󰀸     ±     󰀰 .    󰀰    󰀲    S   a   n    M    i   g   u   e     l     (    T    R     )    󰀱 .    󰀷    󰀳     ±     󰀰 .    󰀱    󰀱    󰀲    󰀹 .    󰀴    󰀹     ±     󰀱 .    󰀸    󰀲    󰀰 .    󰀲    󰀸     ±     󰀰 .    󰀰    󰀱    󰀱 .    󰀲    󰀶     ±     󰀰 .    󰀲    󰀶    󰀲 .    󰀸    󰀱     ±     󰀰 .    󰀱    󰀴    󰀰 .    󰀷    󰀵     ±     󰀰 .    󰀱    󰀰    󰀲 .    󰀹    󰀵     ±     󰀰 .    󰀱    󰀲    󰀱 .    󰀲    󰀱     ±     󰀰 .    󰀱    󰀶    󰀲    󰀷 .    󰀰    󰀸     ±     󰀱 .    󰀸    󰀸    󰀱    󰀰 .    󰀷    󰀱     ±     󰀰 .    󰀸    󰀷    󰀰 .    󰀲    󰀲     ±     󰀰 .    󰀰    󰀶    󰀶 .    󰀶    󰀰     ±     󰀰 .    󰀲    󰀱    󰀰 .    󰀵    󰀰     ±     󰀰 .    󰀱    󰀲    S   a   n    A   n    t   o   n    i   o     (    P    A     )    󰀳 .    󰀲    󰀵     ±     󰀰 .    󰀲    󰀲    󰀱    󰀶 .    󰀳    󰀴     ±     󰀱 .    󰀳    󰀱    󰀰 .    󰀳    󰀶     ±     󰀰 .    󰀰    󰀸    󰀰 .    󰀶    󰀹     ±     󰀰 .    󰀱    󰀴    󰀱 .    󰀷    󰀵     ±     󰀰 .    󰀰    󰀹    󰀰 .    󰀹    󰀱     ±     󰀰 .    󰀱    󰀳    󰀱 .    󰀷    󰀸     ±     󰀰 .    󰀰    󰀷    󰀰 .    󰀲    󰀴     ±     󰀰 .    󰀰    󰀴    󰀲    󰀵 .    󰀵    󰀱     ±     󰀲 .    󰀲    󰀸    󰀳 .    󰀲    󰀰     ±     󰀰 .    󰀳    󰀴    󰀰 .    󰀱    󰀹     ±     󰀰 .    󰀰    󰀵    󰀱 .    󰀹    󰀷     ±     󰀰 .    󰀰    󰀷    󰀰 .    󰀰    󰀹     ±     󰀰 .    󰀰    󰀲    C   a   c   a     l   o   m   a   c    ´   a   n     (    P    A     )    󰀱 .    󰀱    󰀳     ±     󰀰 .    󰀱    󰀰    󰀱    󰀷 .    󰀰    󰀲     ±     󰀱 .    󰀱    󰀲    󰀰 .    󰀲    󰀱     ±     󰀰 .    󰀰    󰀶    󰀰 .    󰀹    󰀱     ±     󰀰 .    󰀱    󰀷    󰀱 .    󰀵    󰀲     ±     󰀰 .    󰀰    󰀸    󰀰 .    󰀶    󰀱     ±     󰀰 .    󰀰    󰀸    󰀱 .    󰀹    󰀹     ±     󰀰 .    󰀰    󰀸    󰀰 .    󰀳    󰀵     ±     󰀰 .    󰀰    󰀸    󰀱    󰀳 .    󰀰    󰀳     ±     󰀰 .    󰀷    󰀶    󰀳 .    󰀴    󰀹     ±     󰀰 .    󰀳    󰀵    󰀰 .    󰀲    󰀰     ±     󰀰 .    󰀰    󰀶    󰀱 .    󰀹    󰀷     ±     󰀰 .    󰀰    󰀷    󰀰 .    󰀱    󰀲     ±     󰀰 .    󰀰    󰀳    C    i   e   r   v    i    t   a     (    P    A     )    󰀰 .    󰀹    󰀵     ±     󰀰 .    󰀰    󰀹    󰀱    󰀱 .    󰀳    󰀱     ±     󰀰 .    󰀷    󰀳    󰀰 .    󰀲    󰀵     ±     󰀰 .    󰀰    󰀵    󰀰 .    󰀹    󰀳     ±     󰀰 .    󰀱    󰀶    󰀵    󰀶 .    󰀸    󰀲     ±     󰀰 .    󰀸    󰀷     ∗     󰀰 .    󰀸    󰀳     ±     󰀰 .    󰀱    󰀵    󰀱 .    󰀲    󰀴     ±     󰀰 .    󰀰    󰀵    󰀰 .    󰀴    󰀴     ±     󰀰 .    󰀱    󰀱    󰀲    󰀱 .    󰀰    󰀴     ±     󰀲 .    󰀶    󰀴    󰀲 .    󰀳    󰀳     ±     󰀰 .    󰀲    󰀶    󰀰 .    󰀱    󰀱     ±     󰀰 .    󰀰    󰀲    󰀹    󰀱 .    󰀲    󰀶     ±     󰀰 .    󰀰    󰀵    󰀰 .    󰀰    󰀷     ±     󰀰 .    󰀰    󰀲     ∗     H    i   g     h   e   r   c   o   n   c   e   n    t   r   a    t    i   o   n .
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