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Air pollution has become a subject of extensive study of several disciplines and it is identified as one of the most damaging factors for the ecosystem and human health. In urban areas, particle emission can be found in suspension and therefore a portion of them is inhalable for humans, or deposited on streets and several surfaces, including lichen’s thallus. We studied particulate matter (PM) (by traffic emission) accumulated in native lichens Parmotrema pilosum in order to carry out a magnetic biomonitoring over 2016 and 2017. For this purpose, the environmental magnetism method was complemented with inductively coupled plasma optical emission spectrometry, scanning electron microscopy, and geostatistical methods. The accumulated iron oxides on lichen’s thallus include potential toxic elements, such as Ba, Cr, Ni, and V. Fe-rich particles related to vehicle emissions correspond to (ultra)fine magnetite of inhalable sizes (PM2.5). Our results indicate a relation between concentration of magnetic particles and areas with high traffic, as well as the influence of rainfall on magnetic PM records. Magnetic biomonitoring is validated as a low-cost and complementary methodology to determine levels of air magnetic PM pollution in cities.

Particulate air pollution in cities comprises a variety of harmful compounds, including fine iron rich particles, which can persist in the air for long time, increasing the adverse exposure of humans and living things to them. We studied street tree (among other species, Cordyline australis, Fraxinus excelsior and F. pensylvanica) barks as biological collectors of these ubiquitous airborne particles in cities. Properties were determined by the environmental magnetism method, inductively coupled plasma optical emission spectrometry and scanning electron microscopy, and analyzed by geostatistical methods. Trapped particles are characterized as low-coercivity (mean ± s.d. value of remanent coercivity Hcr = 37.0 ± 2.4 mT) magnetite-like minerals produced by a common pollution source identified as traffic derived emissions. Most of these Fe rich particles are inhalable (PM2.5), as determined by the anhysteretic ratio χARM/χ (0.1–1 μm) and scanning electron microscopy (

There are limited economic and reliable tools to monitor the effects of airborne particulate matter PM originating from rapid industrialization, urbanization, population growth, and economic development. It is now well established that urban PM contains magnetic particles along with other air pollutants. The velocity and temporal variability of the deposition of such PM on tree leaves are subject to the pollution sources, climate, and local atmospheric conditions. Therefore, these variables have to be taken into account during a biomonitoring. This study presents a magnetic biomonitoring in the city of Queretaro. In the city’s metropolitan area, the most abundant and perennial tree species for biomonitoring is Ficus benjamina. For leaves of this species, the number of days needed for collection NDNC was measured, taking into account the meteorological conditions and the time at which they reached the saturation of airborne PM (pollutants). By means of sequential sampling, we identified that the minimum NDNC after a rainfall > 3 mm is 15 days. In such a period, total suspended particle TSP depositions reach its dynamic equilibrium. This behavior can be observed from measurements of specific magnetic susceptibility χ in Ficus benjamina samples and their comparison with TSP depositions collected with traditional Hi-Vol monitoring systems. After the NDNC calculation, a magnetic monitoring was performed with the biomonitor Ficus benjamina to evaluate the air quality at different sites in the metropolitan area every month for a period of 5 months. Values of χ ranged from 0.45 to 18.52 × 10−8m3kg−1. The species Ficus benjamina can be used as a biomonitor in the city of Queretaro only in seasons (winter-spring) with no or low rainfall. The species has the advantage of providing current PM information about a specific period of time.

During the summer Lake Anónima experiences important changes in salinity and lake level fluctuations. Physicochemical data and field observations indicate that evaporative processes are dominant and that the water inflow is mainly provided by snow meltwater and streams. A multiproxy analysis of data from lake bottom sediments suggests that the main surface stream located south-west of the lake controls the clastic input and the spatial variation of sediment composition. Through an integrated analysis (magnetic, X-ray diffraction and Fourier transform infrared spectroscopy studies) magnetite and greigite minerals were identified in these lake sediments. Such ferrimagnetic minerals have ultra-fine grain sizes (-8 m3 kg-1, remanent coercivity Hcr=49.2 mT and total organic carbon (TOC)=1.11%) and sand facies (e.g. χ=82.1×10-8 m3 kg-1, Hcr=44.7 mT and TOC=0.70%), and four recent depositional sub-environments were identified and characterized in Lake Anónima. This multiparameter analysis contributes to the understanding of present-day lacustrine dynamic and sedimentary processes. Lake Anónima may provide a useful analogue for the interpretation of other lacustrine basins in the Antarctic region.

We assess the element pollution level of water reservoir sediments using environmental magnetism techniques as a novel approach. Although “La Purísima” Water Reservoir is an important source for multiple activities (e.g. recreational, fishing and agricultural) in Guanajuato state, it has been receiving for the last centuries a high load of pollutants by mining extraction, urbanization and land-use change from the Guanajuato Hydrological Basin. The analyses of environmental magnetism, geochemistry, X-ray energy dispersive spectroscopy, scanning electron microscopy and multivariate methods were applied to study sediments from the reservoir and basin. Accordingly, they indicate the presence of iron oxides (magnetite and hematite) and iron sulfides (pyrite and greigite), which evidences relevant differences in particle size and concentration within the water reservoir (median mass-specific magnetic susceptibility χ = 23.2 × 10−8 m3/kg), as well as with respect to the river basin sediments (median χ = 88.8 × 10−8 m3/kg). The highest enrichment factor EF values (median values of EF = 2–10 for As, Co, Ba, Cu, Cd, Ni and EF > 20 for S) are mainly associated with historical mining activities that have led to an enrichment of potentially toxic elements on these water reservoir sediments. We propose the use of concentration and grain size dependent magnetic parameters, i.e. χ, remanent magnetizations and anhysteretic ratios ARM/SIRM and χARM/χ, as proxies for Ba, Co, Cr, Ni, P and Pb pollution in these river and water reservoir sediments. Such parameters allow to evaluate this sedimentary environment, and similar ones, through useful and convenient proxies. Fil: Chaparro, Marcos Adrián Eduardo. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; Argentina Fil: Ramírez Ramírez, Margarita. Universidad de Guanajuato. División Ciencias de la Vida; México Fil: Chaparro, Mauro Alejandro Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Matemática; Argentina Fil: Miranda Avilés, Raúl. Universidad de Guanajuato; México Fil: Puy Alquiza, María Jesús. Universidad de Guanajuato; México Fil: Böhnel, Harald N.. Universidad Nacional Autónoma de México. Centro de Geociencias; México Fil: Zanor, Gabriela Ana. Universidad de Guanajuato. División Ciencias de la Vida; México

Shrub barks can accumulate airborne particles and seem to be suitable biological monitors for assessing air pollution. We studied the bark of the species Bursera fagaroides as a biomonitor of air pollution in an urban area of Mexico. Samples were collected in dry and rainy seasons during 2011 and 2012, in 28 sites which are exposed to magnetic pollutants emitted by different human activities (industrial point-sources and vehicular emissions). Environmental magnetism studies allow determining mineralogy, concentration and grain size of magnetic particles accumulated in barks, providing information on the sources and characteristics of their emitted particles. Magnetic properties of all samples were determined by environmental magnetism method. The highest values of magnetic concentration dependent parameters were observed in industrial and vehicular traffic sites. The mean values of saturation of isothermal remanent magnetization SIRM for dry seasons are two to threefold (SIRM = 0.8–1.2 × 10−3Am2kg−1) the mean value for rainy season (SIRM = 0.4 × 10−3Am2kg−1). The integrated magnetic analysis indicates the presence of ferrimagnetic minerals, mostly magnetite-like (remanent coercivity Hcr = 31.6–38.7 mT) particles of small sizes (1 –

Single crystal alloys Cu-22.64 Al- 8.26 Mn and Cu-23.33 Al- 9.42 Mn (at. %) are studied by means of differential scanning calorimetry, electrical resistometry and thermomagnetic techniques. Order-disorder transitions were identified and the critical temperatures are compared with the values obtained by Monte Carlo simulations. Evidences of spinodal decomposition and magnetic transitions are discussed.

A mathematical model for understanding parasitism is proposed and developed. This model allows us to trace a distinction between the phenomena of parasitism and parasitic disease, respectively. The philosophical and theoretical framework for this model is Bunge’s systemic ontology. Parasitism is understood as a biological subsystem, which can result in parasitosis or parasitic disease when destabilizing factors are present.

The use of environmental magnetism methods and biomonitors allows us the development of a low-cost tool for assessing atmospheric pollution through trapped magnetic particulate matter. Such particles concentration was monitored in situ, on the lichen's thallus, using magnetic susceptibility as a pollution proxy. We studied the magnetic particle distribution on the thallus surface from weekly measurements of in situ magnetic susceptibility κis during 16 months for seven sites. A total of ∼8300 measurements was carried out; and mean overall κis values for each lichen varied between 4.1 and 23.9 × 10−5SI revealing the influence of different atmospheric pollution sources on Parmotrema pilosum, such as metallurgical factories and vehicular emissions. Weekly measurements of κis show areas of magnetic accumulation on the thallus over a period of 60 measurement campaigns. Iron rich spherules and irregular particulate matter between PM2.5 and PM1.0 were observed by SEM-EDS. A joint analysis of meteorological variables and magnetic susceptibility shows an inverse relation between this magnetic parameter and temperature, i.e., a trend of decreasing κis values during seasons of higher temperatures which tend toward higher values of atmospheric mixing height. Precipitation also affects the magnetic signal over time, producing decreases in mean values of κis after rainy periods. Fil: Marié, Débora Carolina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; Argentina Fil: Chaparro, Marcos Adrián Eduardo. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; Argentina Fil: Lavornia, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Tierra del Fuego; Argentina. Universidad Nacional del Centro de la Provincia de Buenos Aires; Argentina Fil: Sinito, Ana Maria. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; Argentina Fil: Castañeda Miranda, Ana G.. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; Argentina Fil: Gargiulo, José Daniel. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; Argentina Fil: Chaparro, Mauro Alejandro Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Mar del Plata; Argentina Fil: Böhnel, Harald N.. Universidad Nacional Autónoma de México; México

The natural radionuclide (238U, 232Th, and 40K) content of the 15 rock samples collected from Kolli hills along the Eastern Ghats, India, has been analyzed using a 4″ × 4″ NaI (Tl) scintillation detector-based gamma-ray spectrometer. The activity concentrations of 238U, 232Th, and 40K were between 12.97–49.89, 6.4–27.05, and 51.85–95.84 Bq kg−1, respectively. To understand the entire radiological characteristics of the collected samples, the various radiological hazard parameters have been calculated and were compared with the global recommended mean values. From the magnetic studies, values of χ ranged from 33.1 to 510.7 × 10−8 m3 kg−1. Moreover, in rock samples of Kolli hills, ferrimagnetic minerals are found to be the main magnetic carrier. Statistical analyses were performed to study the relation between the natural radionuclides, radiological hazard parameters, and magnetic minerals. The results of Pearson’s correlation analysis shows that 238U and 232Th strongly correlate with the radiological hazard parameters, and a poor correlation was noted between magnetic and radiological parameters. However, a positive and a near-positive correlation was also observed between SIRM/χ (0.501–0.578) and κFD% (0.471–0.481) with U and Th activity concentrations, respectively. This indicates that the carrier and grain size dependence parameters also play a significant role in increasing the activity concentrations of U and Th and its associated radiological parameters. From the cluster analysis, it is found that the content of ferrimagnetic minerals is higher in sample nos. 4, 5, 11, and 12, which greatly improves the properties of concrete when used for building construction purposes. Fil: Krishnamoorthy, Nanjundan. Csi College Of Engineering; India Fil: Kerur, Basavaraj Rachappa. Gulbarga University; India Fil: Mullainathan, Sundaram. Thiru. Vi. Ka. Government Arts College; India Fil: Chaparro, Marcos Adrián Eduardo. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; Argentina Fil: Murugesan, Sugumaran. Sathyabama University; India Fil: Chaparro, Mauro Alejandro Eduardo. Centro Marplatense de Investigaciones Matemáticas (CEMIM-UNMDP-CONICET); Argentina

Fil: Chaparro, Marcos Adrian Eduardo. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Tandil. Centro de Investigaciones En Fisica E Ingenieria del Centro de la Provincia de Buenos Aires; Argentina

South India is one of the regions in the world that has the highest background radiation levels. In this region, river sediments are used in large quantities as building material. Therefore, the knowledge of the radionuclides distribution in such sediments is important for assessing their potential adverse effects on humans residing in buildings made of sediment material. For this goal, we focus on the determination of the natural radioactivity levels and magnetic properties in sediment samples collected from 33 locations along the southwestern Bharathapuzha river originating from the Anamalai hills. The sediment samples were subdivided into two categories according to particle size. It is observed that the average activity concentrations of 226Ra, 232Th, and 40K in sediment samples varied greatly with granulometric and geological differences. The average values of 226Ra, 232Th, and 40K and its associated radiological hazard parameters for category II samples (particle size between 149 μm and 2 mm) were lower than category I sediment samples (bulk samples). Moreover, the average radionuclide activity concentrations (except for 40K) and the calculated radiation hazard parameters are higher in the lowland region compared to the highland and the midland regions. The mass-specific magnetic susceptibility values ranged widely along the river, as well as between physiographic regions, e.g., average values for category I sediment samples were 950.2 × 10−8, 351.1 × 10−8 and 131.8 × 10−8 m3 kg−1 (for high-, mid- and lowland regions, respectively). Differences between physiographic regions and sediment fractions from both radioactivity determinations and magnetic parameters were analyzed with statistical tests and multivariate analysis, which showed the advantages of using both independent techniques. Fil: Krishnamoorthy, N.. CSI College of Engineering; India Fil: Mullainathan, S.. Thiru.Vi.Ka Govt.Arts College; India Fil: Chaparro, Marcos Adrián Eduardo. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; Argentina Fil: Chaparro, Mauro Alejandro Eduardo. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales; Argentina Fil: Mehra, R.. Dr. B. R. Ambedkar National Institute of Technology; India

Natural and anthropogenic activities along the coastal region of densely populated Kerala may introduce hazardous components into the coastal environment. The present study aimed to investigate the sources and impacts of hazardous components in beach sediments by environmental magnetism methods as additional tools. Magnetic parameters (such as mass-specific magnetic susceptibility χ = − 1.2-154.4 × 10− 8 m3 kg− 1) and ratios that describe the magnetic properties of minerals such as Fe-oxides, indicate variable concentration of mixtures of magnetite and hematite (magnetite/hematite). The direct significant relationships between the variables indicate that higher concentration magnetic parameters are associated with higher radionuclides and metal contents. Magnetic properties and multivariate statistical analyses evidence the presence of contrasting groups defined only using a reduced number of magnetic variables. One of these groups, the central area of the Kerala coastline, showed the highest magnetic concentrations of mixtures of magnetite/hematite and higher values (up to 6.7) of pollution load index because of extensive anthropogenic activities. Fil: Chaparro, Marcos Adrián Eduardo. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; Argentina Fil: Suresh, G.. Theivanai Ammal College for Women (Autonomous); Tailandia Fil: Chaparro, Mauro Alejandro Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Mar del Plata; Argentina Fil: Ramasamy, V.. Annamalai University; Tailandia Fil: Sundarrajan, M.. Sri Chandrasekharendra Saraswathi Viswa Mahavidyalaya; Tailandia

Air pollution is a basic problem nowadays and it requires special concern. In India, the air pollution is a growing problem because of the enhanced anthropogenic activities such as burning fossil fuels involving industrial processes and motor vehicles. We study airborne dust particles collected at the height of 7 m in roadside and land area from thirty-eight cities in the state of Tamil Nadu. The collection involves a total of 111 samples concerning vehicular, industrial and residential areas, and allows us to assess the spatial distribution of magnetic particles produced and emitted on a short period of time (about one month). Magnetic properties of these air suspended particles were determined by techniques of environmental magnetism, revealing the presence of magnetite and hematite. We found the overall average of mass-specific magnetic susceptibility χ of 589.0 × 10−8 m3 kg−1 and saturation of remanent magnetization SIRM of 68.1 × 10−3 A m2 kg−1; as well as χ and SIRM values higher than 900.0 × 10−8 m3 kg−1 and 700.0 × 10−3 A m2 kg−1, respectively, corresponding to the most impacted zones in industrial/vehicular areas and in cities located in the central/eastern region respectively (e.g.: Hosur, Krishnagiri, Salem, Dharapuram, Ranipet, Ayanavaram, Cuddalore and Chidambaram). We analyzed the relationship between magnetic parameters, between areas and possible grouping of cities using multivariate statistical analysis. The SEM-EDS observations and grain size estimations reveal the presence of trace elements (Sb, Zn, Co, Ni, As and V) and fine particles (1–5 μm) that can be inhaled and therefore are dangerous to human health. Fil: Gargiulo, José Daniel. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; Argentina Fil: Kumar, R. Senthil. T.J.S. Engineering College. Department of Physics; India Fil: Chaparro, Mauro Alejandro Eduardo. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; Argentina Fil: Chaparro, Marcos Adrián Eduardo. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales; Argentina Fil: Natal, Marcela. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales; Argentina Fil: Rajkumar, P.. Sethupathy Govt. Arts College; India

Hydrological systems of the ice-free areas of the James Ross archipelago (NE Antarctic Peninsula) provide a unique opportunity for studying recent environmental changes associated with the current Global Warming. Geochemical, hydrological, sedimentological, and magnetic studies were carried out on different lake systems and ephemeral ponds from post-Holocene periglacial environments to characterize their natural variability. Significant differences between the lakes were observed based on physicochemical analyses, and can be attributed to several characteristics and processes taking place (geochemical,diagenetic, biological, etc.) in individual lake catchments. Seymour-Marambio Island?s lakes exhibit high total dissolved solids (*3.300 mg L-1) due to thehigh rate of evaporation in the region, whereas trace elements show differences in the lithological source. Lakes from Vega and James Ross islands are comparatively diluted, with the highest pH values up to 10.2. Within VegaIsland, trace elements discriminate lakes into sectors which show statistical differences due to variations in lithological sources. Dissolved sources can be divided according to their kinetics into: high-rate processes which occur duringsummer months (evaporation, salt precipitation, atmospheric precipitation, melting processes) and low-rate processes (mineral weathering, giving a long-term signature). The present multidisciplinary study contributes to abetter understanding of Antarctic lake systems, and can be used as a baseline dataset for further studies investigating the impact of recent climate changes on the biological and geochemical characteristics of these pristine ecosystems in the future. Fil: Lecomte, Karina Leticia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Ciencias de la Tierra. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Investigaciones en Ciencias de la Tierra; Argentina Fil: Vignoni, Ana Paz. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; Argentina Fil: Cordoba, Francisco Elizalde. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia de Jujuy. Universidad Nacional de Jujuy. Centro de Investigaciones y Transferencia de Jujuy; Argentina Fil: Chaparro, Marcos Adrián Eduardo. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; Argentina Fil: Kopalova, Katerina. Faculty Of Science, Department Of Ecology, University; República Checa Fil: Gargiulo, José Daniel. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; Argentina Fil: Lirio, Juan Manuel. Ministerio de Relaciones Exteriores, Comercio Interno y Culto. Dirección Nacional del Antártico. Instituto Antártico Argentino; Argentina Fil: Irurzun, Maria Alicia. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; Argentina Fil: Bohnel, Harald. Universidad Nacional Autónoma de México. Centro de Geociencias; México

In this contribution, a methodology is reported in order to build an interval fuzzy model for the pollution index PLI (a composite index using relevant heavy metal concentration) with magnetic parameters as input variables. In general, modelling based on fuzzy set theory is designed to mimic how the human brain tends to classify imprecise information or data. The “interval fuzzy model” reported here, based on fuzzy logic and arithmetic of fuzzy numbers, calculates an “estimation interval” and seems to be an adequate mathematical tool for this nonlinear problem. For this model, fuzzy c-means clustering is used to partition data, hence the membership functions and rules are built. In addition, interval arithmetic is used to obtain the fuzzy intervals. The studied sets are different examples of pollution by different anthropogenic sources, in two different study areas: (a) soil samples collected in Antarctica and (b) road-deposited sediments collected in Argentina. The datasets comprise magnetic and chemical variables, and for both cases, relevant variables were selected: magnetic concentration-dependent variables, magnetic features-dependent variables and one chemical variable. The model output gives an estimation interval; its width depends on the data density, for the measured values. The results show not only satisfactory agreement between the estimation interval and data, but also provide valued information from the rules analysis that allows understanding the magnetic behaviour of the studied variables under different conditions.

Gastrointestinal parasitism is one of the diseases that has the highest economic impact on the Argentinian beef production system, rendering it inefficient. In the region of the Humid Pampas, it has been estimated that 22 million dollars are lost annually because of the death of calves and 170 million dollars are lost in sub-clinic costs. A mathematical model with fuzzy parameters was constructed for the analysis of the free-living stages of gastrointestinal parasites, with the purpose of estimating the pool of L3 larvae available for migration to pasture and the levels of infection in pasture at any time of the year under different climatic conditions. The model is formulated in terms of a system of three difference equations. These equations describe the abundance of parasites in each of the successive stages of the population development. The model was calibrated and tested with data gathered through fieldwork carried out in Tandil (37°19′S, 59°08′05″W), province of Buenos Aires (Argentina) and the corresponding weather data. A comparison between model simulations and fieldwork data obtained in other locations achieved satisfactory results.

Ostertagia ostertagi is a nematode, predominantly affecting cattle in the Pampean region of Argentina. A mathematical model parametrized using fuzzy rule-based systems of the Takagi-Sugeno-Kant type (FTSK) for estimating the development time from egg to infecting larval stage L3 of the gastrointestinal parasite O. ostertagi is here proposed. The estimation of development time of O. ostertagi is essential for the generation of appropriate control mechanisms, since this provides information about the time when parasites are ready to migrate to pastures. For the purpose of reflecting the natural environmental conditions, the mean daily temperature is taken as the main and only regulator of the development time. Humidity conditions are considered to be sufficient for the normal development of the larvae. Hence the individual's daily growth is a function of its length and the mean temperature recorded on the previous day. It is expressed in terms of a difference equation with fuzzy parameters, which are defined using laboratory data. Model outputs are tested against results of field experiments. Simulation results are very satisfactory, yielding a mean estimation error (MEE) of 0.64 weeks, with variance 0.34, and a determination coefficient R 2 = 0.74. The model clearly exhibits an inverse relationship between development time and temperature both in controlled and in field conditions. It also exhibits a very sensitive response both to the order in which the temperature sequence occurs, – reproducing the differences observed between spring and autumn – and to the amplitude of the temperature range.

This contribution constitutes a new study using magnetic parameters and trace element determinations of pollutants in river sediments from the Tamil Nadu state. The Vellar River covers a total length of about 200 km and flows into the Bay of Bengal. Sediment samples were collected at different sediment depths (up to 90 cm) from 12 sites to investigate their magnetic properties (27 samples) and the contents of trace elements (21 out of 27 samples) along the river; as well as to perform magnetic studies for various grain size fractions (16 sub samples). The magnetic results of magnetic susceptibility and remanent magnetizations suggest that the magnetic signal of these sediments is controlled by ferrimagnetic minerals magnetite-like minerals and a minor contribution of antiferromagnetic carriers (such as hematite minerals). Detailed studies of selected samples showed a higher magnetic concentration in finer grain-sized fractions and a slightly different magnetic mineralogy. Magnetic concentration-dependent parameters evidenced high values, which, together with the background values, allowed us to identify magnetic enhancement at some sites. The Pearson correlation and multivariate statistical studies (Principal Component Analysis, Canonical Correlation Analysis) supported the relationship between the magnetic and chemical variables; in particular, magnetic susceptibility, anhysteretic and isothermal remanent magnetization are closely correlated to Co, Cr, Cu, Fe, V, Zn, and the pollution load index. In addition, Principal Coordinate Analysis and fuzzy C-means cluster analysis allowed us to make a classification and to perform a magnetic-chemical characterization of the data into four groups, thereby identifying critical (possibly polluted) sites from the Vellar River.

Rock-magnetic techniques have become a useful tool in environmental issues; in particular, magnetic studies constitute an alternative way to study pollution in different media. The present contribution focuses on magnetic parameters as pollution indicators, especially from their relationship with contents of heavy metals. The work was carried out in two Indian rivers located in Tamil Nadu, southern India. Several sediment samples were collected and studied in the laboratory using magnetic techniques, magnetic susceptibility, anhysteric remanent magnetization, isothermal remanent magnetization, and chemical techniques to determine contents of heavy metals. Magnetic mineralogy indicates the predominance of ferrimagnetic minerals; although magnetite-like minerals are the main magnetic carriers, antiferromagnetic minerals can be present as subordinate carriers. Concentration-dependent magnetic parameters revealed noticeable differences between both rivers, e.g. magnetic susceptibility is four times higher in Cauvery than in Palaru River. Moreover, such increase can be interpreted as “magnetic enhancement” and therefore related to the pollution status. This magnetic enhancement indicated a different pollutant contribution in both rivers, and also, a different spatial distribution along these rivers, where critical (or more polluted) sites were identified. On the other hand, univariate and multivariate statistical analyses—e.g. PCoordA, Multifactorial Analysis of distance, PCA and RDA—were examined, revealing a link between magnetic and chemical variables. Among magnetic parameters, the concentration-dependent magnetic parameters (e.g. magnetic susceptibility) seem to be the most relevant for this study.

Some epiphytic species accumulate airborne particles and are suitable biological indicators for monitoring urban and industrial pollution. The species Tillandsia recurvata L. was studied as a monitor of air pollution in an urban area from Mexico. Individuals were collected in 25 sites which are exposed to different pollution degree and sources.The magnetic particle concentration, particle size, and mineralogy were determined and compared with chemical contents for all samples. The highest values of magnetic concentration dependent parameters were observed in industrial and heavy traffic sites (e.g., mass specific magnetic susceptibility of up to 171.5 ¡Á 10−8 m3 kg−1). In contrast, sites with low or without vehicular traffic reached low values (e.g., mass specific magnetic susceptibility of down to 1.8 ¡Á 10−8 m3 kg−1). The integrated magnetic analysis (King´s and Day´s plots, remanent magnetization parameters and thermomagnetic measurements) revealed the presence of ferromagnetic minerals, mostly magnetite-like with fine grain sizes (0.1¨C1 ¦Ìm) and subordinate presence of high-coercivity minerals. Selected samples were observed by SEM and EDS analysis and revealed the presence of Fe-rich particles, as well as trace elements, among others, As, Sb, S, Cr, Mo, V, Zn, Ba, Hg, Pt and Cu. Most of the elements detected by EDS were also quantified by ICP-MS measurements.Multivariate statistical analyses prove a high correlation between magnetic parameters and elements, as well as allow us classifying sites in clusters (fuzzy c-means clustering) with different pollution degree. These results demonstrate the usefulness of the species T. recurvata L. as a passive pollution monitor, with an affordable and immediate application. This species is abundant not only in Mexico, but also in other cities from America. Fil: Castañeda Miranda, Ana Gabriela. Universidad Nacional Autónoma de México; México Fil: Chaparro, Marcos Adrián Eduardo. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto de Física Arroyo Seco; Argentina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Tandil. Sede Tandil del Centro de Investigaciones En Fisica E Ingenieria del Centro de la Provincia de Buenos Aires; Argentina Fil: Chaparro, Mauro Alejandro Eduardo. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Tandil. Sede Tandil del Centro de Investigaciones En Fisica E Ingenieria del Centro de la Provincia de Buenos Aires; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales; Argentina Fil: Bhönel, Harald N.. Universidad Nacional Autónoma de México; México

Several statistical analyses—as alternative tools—were applied to magnetic monitoring studies. Magnetic and chemical data from two environments have been gathered from previous papers and studied separately. Univariate and multivariate analyses were first examined, revealing a link between magnetic and chemical variables. The latter analyses, in particular, canonical correlation analysis, showed very good canonical correlations: R = 0.950 (Antarctica) and R = 0.891 (Argentina). On the other hand, in order to classify the data according to the degree of contamination, principal coordinates and discriminant analyses, as well as the comparison of several multivariate means were performed. Three groups were distinguished in both case studies, which were well classified at a low margin of error and quite different from each other at a significant level: 0.01 (Antarctica) and 0.05 (Argentina). The joint use of these statistical analyses also showed, in agreement with previous studies, that the relevant variables in order to identify atmospheric pollution are: magnetic susceptibility, saturation of isothermal remanent magnetisation, anhysteric susceptibility/magnetic susceptibility, remanent coercivity, and copper, lead, zinc and chromium contents.

Studies of magnetic monitoring for assessing air pollution have been proposed as alternative and complimentary of chemical methods. Such magnetic studies provide measurements at low cost and relative promptness. In this work, we present and apply a methodology to build an interval fuzzy model, which calculates the Tomlinson pollution load index (PLI). The input variables for the model are magnetic parameters relative to magnetic concentration, grain size and mineralogy. The model aims to two purposes, on one hand, to calculate the values of PLI only using magnetic variables and, on the other hand, to analyze the relationship between magnetic and chemical variables. The studied dataset was obtained from measurements of the biomonitor Tillandsia recurvata L. in a Mexican urban area (Santiago de Querétaro). The best model was selected from a total of about half a million possible models using a fitness measure (RIF). The model yields a satisfactory approximation of the PLI data and it was concluded that PLI increases with relation to: an increase in concentration of magnetic materials, an additional contribution to the magnetic signal of paramagnetic materials, and an increase in size of magnetic grains. Fil: Chaparro, Mauro Alejandro Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales; Argentina Fil: Chaparro, Marcos Adrián Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; Argentina Fil: Castaneda Miranda, A. G.. Universidad Nacional Autónoma de México. Centro de Geociencias; México Fil: Böhnel, Harald N.. Universidad Nacional Autónoma de México. Centro de Geociencias; México Fil: Sinito, Ana Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; Argentina

In recent years, the number of studies of pollution and magnetic proxies for environmental pollution in developed countries, especially European and North American countries, has gradually increased from the 80’s to date. Despite this trend that shows a positive interest in taking care of the environment and researching into the environmental impact of several human activities, pollution studies in Latin American countries have been reducing in number. Moreover, studies of magnetic proxies for pollution are scarce; in particular, studies of this nature has been carried out in Argentina over the past few years by Chaparro and coworkers. Studies of magnetic enhancement in soils due to the burning mechanism are discussed and the results of burnt soils affected by fires of different nature and natural soils are compared, taking into account their magnetic carriers. Nevertheless, this article deals mainly with the first studies of magnetic proxies for pollution conducted in a province in Argentina. Soils, lagoon and stream sediments from three areas were studied. These areas comprise La Plata, Chascomús, and Tandil districts. The influence of pollution was investigated in Tandil and La Plata, revealing magnetic enhancement and the presence of pollutants only in Tandil soils. On the other hand, stream and lagoon sediments were studied in La Plata and Chascomús. Magnetic carriers and the contents of some heavy metals were identified and investigated in both areas separately. Magnetic parameters show distinctive points and wide areas affected by pollution. Furthermore, this magnetic inference is supported by high contents of heavy metals, especially lead and zinc. Finally, a new statistical study of multiple correlation analysis concerning data from La Plata and Chascomús areas was tried in order to investigate the existence of a linear relation between sets of several magnetic parameters and several chemical variables.

The activity concentration of the natural radionuclides 226Ra, 232Th and 40K was measured for sediment samples collected from thirty-three different locations along the Bharathapuzha river basin by using high-resolution gamma-ray spectrometry. The concentrations of the natural radionuclides were found to vary from location to location, and their mean values are 19.6, 82.87 and 19.44 % higher than the worldwide mean values of 226Ra, 232Th and 40K, respectively. The value of 232Th was found to be higher than that of 226Ra in 82 % of the samples collected for this study. The calculated values of indoor gamma dose rate (DIN) ranged between 89.55 and 194.24 nGy h-1, and the overall mean value is 63.2 % higher than the recommended safe and criterion limit by UNSCEAR. The internal and external hazard indices (Hin and Hex), the representative gamma index and alpha index (Igamma and Ialpha), the annual gonad dose equivalent (AGDE) and the excess lifetime cancer risk (ELCR) were also calculated and compared with the international recommended values. Multivariate statistical analyses were also carried out to determine the relation between the natural radionuclides and various radiological parameters. Fil: Krishnamoorthy, N.. Bharathiar University. Research and Development Centre; India. CSI College of Engineering. Department of Physics; India Fil: Mullainathan, S.. AVC College of Engineering. Department of Physics; India Fil: Mehra, R.. Dr. B. R. Ambedkar National Institute of Technology. Department of Physics; India Fil: Chaparro, Marcos Adrián Eduardo. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto de Fisica Arroyo Seco; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; Argentina Fil: Chaparro, Mauro Alejandro Eduardo. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto Multidisciplinario de Ecosistemas y Desarrollo Sustentable; Argentina

The natural radioactivity levels and magnetic measurements in sediment samples of Bharathapuzha river for the first time have been determined. Bottom sediments from 33 locations were collected to determine 226Ra, 232Th and 40K using a HPGe detector based on the high-resolution gamma spectrometry system, and magnetic susceptibility by using Bartington MS2 magnetic susceptibility meter. The calculated activity concentrations of 226Ra, 232Th and 40K have been found to vary from 21.21 to 66.03 Bq kg−1, 33.49 to 93.10 Bq kg−1 and 232.25 to 899.66 Bq kg−1, respectively. The results have been compared with worldwide recommended values and also with radioactivity measurements in river sediments of India and other parts of the world. The air-absorbed dose rate, indoor and outdoor annual effective dose rates and radium equivalent activity are calculated with an aim to access the radiation hazards arising due to the use of these materials in the construction of buildings and their mean values obtained are 74.83 nGy h−1, 367.08 μSv y−1, 91.77 μSv y−1 and 157.09 Bq kg−1, respectively. The mass-specific magnetic susceptibility values ranged widely from 35.4 to 2,160.5 × 10−8 m3 kg−1 and compared with other rivers in South India. Multivariate statistical analyses were performed to describe the magnetic and radioactivity relevance of the different groups of samples. The data obtained in the present study may be useful for radiological and magnetic mapping of the study area in the future. Fil: Krishnamoorthy, N.. Bharathiar University; India. CSI College of Engineering; India Fil: Mullainathan, S.. AVC College of Engineering; India Fil: Mehra, R.. Dr. B R Ambedkar National Institute of Technology; India Fil: Chaparro, Marcos Adrián Eduardo. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto de Fisica Arroyo Seco; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Chaparro, Mauro Alejandro Eduardo. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto Multidisciplinario de Ecosistemas y Desarrollo Sustentable; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

The model here presented describes the dynamics of adult Ostertagia ostertagi parasites in cattle in the field. The model also describes the population of infecting L3 larvae subject to the conditioning process while in the pasture as well as the inhibition–disinhibition process in ingested L4 larvae. The model has two modules: one for the conditioning process and the other for the parasitic stage. The first module determines the proportion of ingested L3 larvae that will go through an arrested stage of development, or hypobiosis, and for how long depending on the weather conditions and the length of the period of exposure in the pasture. The second one describes the adult population dynamics as disinhibiting larvae and recently ingested larvae accumulate in the animal. The model has a discrete daily step and is parameterized using fuzzy inference systems of the Mamdani type (FM). Given that the inhibition–disinhibition process is not yet fully understood, a series of perturbations on the different input variables were performed with the purpose of analysing the model's behavior. Simulations show that the adult population exhibits two maximal peaks of infection in the hosts in December–January (Summer) and April–May (Autumn). These high values are a consequence of hypobiotic larvae resuming their development at those times. Fil: Chaparro, Mauro Alejandro Eduardo. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto Multidisciplinario de Ecosistemas y Desarrollo Sustentable; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Canziani, Graciela Ana. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto Multidisciplinario de Ecosistemas y Desarrollo Sustentable; Argentina Fil: Fiel, Cesar Alberto. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Veterinarias. Departamento de Sanidad Animal y Medicina Preventiva; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

The Ponnaiyar River is one of the largest rivers of the Tamil Nadu state (India), flowing a distance of 430 km from its point of origin to the sea. This work contributes with new data of magnetic and elemental composition of river sediments, and improves the knowledge obtained by preliminary and previous studies of rivers from Southeastern India. Magnetic susceptibility, anhysteretic and isothermal remanent magnetization and chemical determinations (major and trace metals) were measured. Magnetic results reveal the predominance of magnetite-like mineral with magnetic grain size variations along the river and in depth. Most of the uppermost samples have the major presence of trace metals and higher values of magnetic concentration. Magnetic and chemical variables were also analysed as potential pollution indicators using multivariate statistical techniques: canonical correlation and fuzzy c-means clustering analyses, which confirmed the existence of relationships, but not in a simple way, between magnetic and chemical variables. Furthermore, fuzzy analysis allows classifying the data in different well-differentiated groups regarding the trace metal load, concentration and feature-dependent parameters. The most polluted samples show high concentration of trace elements and magnetic carriers, softer and coarser magnetic minerals; on the contrary, the unpolluted samples (from the deepest sediments) have the opposite characteristics. Fil: Chaparro, Marcos Adrián Eduardo. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto de Fisica Arroyo Seco; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Govindhasamy, Suresh. Arulmigu Meenakshi Amman College of Engineering; India Fil: Chaparro, Mauro Alejandro Eduardo. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto Multidisciplinario de Ecosistemas y Desarrollo Sustentable; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Ramasamy, V.. Annamalai University; India Fil: Sinito, Ana Maria. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto de Fisica Arroyo Seco; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina