Search results for: forensic soils analysis

Authors: Melik Kara, Gulsah Tulger Kara

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The soil is a crucial component of the ecosystem, and in industrial and urban areas it receives large amounts of trace elements from several sources. Therefore, accumulated pollutants in surface soils can be transported to different environmental components, such as deep soil, water, plants, and dust particles. While elemental contamination of soils is caused mainly by atmospheric deposition, soil also affects the air quality since enriched trace elemental contents in atmospheric particulate matter originate from resuspension of polluted soils. The objectives of this study were to determine the total and leachate concentrations of trace elements in soils of city area in Izmir and characterize their spatial distribution and to identify the possible sources of trace elements in surface soils. The surface soil samples were collected from 20 sites. They were analyzed for total element concentrations and leachate concentrations. Analyses of trace elements (Ag, Al, As, B, Ba, Be, Bi, Ca, Cd, Ce, Co, Cr, Cs, Cu, Dy, Er, Eu, Fe, Ga, Gd, Hf, Ho, K, La, Li, Lu, Mg, Mn, Mo, Na, Nd, Ni, P, Pb, Pr, Rb, Sb, Sc, Se, Si, Sm, Sn, Sr, Tb, Th, Ti, Tl, Tm, U, V, W, Y, Yb, Zn and Zr) were carried out using ICP-MS (Inductively Coupled Plasma-Mass Spectrometer). The elemental concentrations were calculated along with overall median, kurtosis, and skewness statistics. Elemental composition indicated that the soil samples were dominated by crustal elements such as Si, Al, Fe, Ca, K, Mg and the sea salt element, Na which is typical for Aegean region. These elements were followed by Ti, P, Mn, Ba and Sr. On the other hand, Zn, Cr, V, Pb, Cu, and Ni (which are anthropogenic based elements) were measured as 61.6, 39.4, 37.9, 26.9, 22.4, and 19.4 mg/kg dw, respectively. The leachate element concentrations were showed similar sorting although their concentrations were much lower than total concentrations. In the study area, the spatial distribution patterns of elemental concentrations varied among sampling sites. The highest concentrations were measured in the vicinity of industrial areas and main roads. To determine the relationships among elements and to identify the possible sources, PCA (Principal Component Analysis) was applied to the data. The analysis resulted in six factors. The first factor exhibited high loadings of Co, K, Mn, Rb, V, Al, Fe, Ni, Ga, Se, and Cr. This factor could be interpreted as residential heating because of Co, K, Rb, and Se. The second factor associated positively with V, Al, Fe, Na, Ba, Ga, Sr, Ti, Se, and Si. Therefore, this factor presents mixed city dust. The third factor showed high loadings with Fe, Ni, Sb, As, Cr. This factor could be associated with industrial facilities. The fourth factor associated with Cu, Mo, Zn, Sn which are the marker elements of traffic. The fifth factor presents crustal dust, due to its high correlation with Si, Ca, and Mg. The last factor is loaded with Pb and Cd emitted from industrial activities.

Keywords: trace elements, surface soil, source apportionment, Izmir

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Authors: Siti Khadijah Che Osmi, Syed Mohd Ahmad

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This paper presents a methodology to develop fragility curves for shallow tunnels so as to describe a relationship between seismic hazard and tunnel vulnerability. Emphasis is given to the influence of surrounding soil material properties because the dynamic behaviour of the tunnel mostly depends on it. Four ground properties of soils ranging from stiff to soft soils are selected. A 3D nonlinear time history analysis is used to evaluate the seismic response of the tunnel when subjected to five real earthquake ground intensities. The derived curves show the future probabilistic performance of the tunnels based on the predicted level of damage states corresponding to the peak ground acceleration. A comparison of the obtained results with the previous literature is provided to validate the reliability of the proposed fragility curves. Results show the significant role of soil properties and input motions in evaluating the seismic performance and response of shallow tunnels.

Keywords: fragility analysis, seismic performance, tunnel lining, vulnerability

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Authors: Jacqueline Michella Anak Nathen

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Subgrade soil is an essential component in the design of road structures as it provides lateral support to the pavement. One of the main reasons for the failure of the pavement is the settlement of the subgrade and the high susceptibility to moisture, which leads to a loss of strength of the subgrade. Construction over weak or soft subgrade affects the performance of the pavement and causes instability of the pavement. If the mechanical properties of the subgrade soils are lower than those required, the soil stabilisation method can be an option to improve the soil properties of the weak subgrade. Soil stabilisation is one of the most popular techniques for improving poor subgrade soils, resulting in a significant improvement in the subgrade soil’s tensile strength, shear strength, and bearing capacity. Soil stabilisation encompasses the various methods used to alter the properties of soil to improve its engineering properties. Soil stabilisation can be broadly divided into four types: thermal, electrical, mechanical, and chemical. The most common method of improving the physical and mechanical properties of soils is stabilisation using binders such as cement and lime. However, soil stabilisation with conventional methods using cement and lime has become uneconomical in recent years, so there is a need to look for an alternative, such as fiber. Although not a new technique, adding fiber is a very practical alternative to soil stabilisation. Various types of fibers, such as natural, synthetic, and waste fibers, have been used as stabilising agents to improve the strength and durability of subgrade soils. This review provides a comprehensive comparison of the effectiveness of natural, synthetic, and waste fibers in stabilising subgrade soils.

Keywords: subgrade, soil stabilisation, pavement, fiber, stabiliser

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Authors: Nikhil John Kollannur, Dali Naidu Arnepalli

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Most of the surface related phenomena in the case of fine-grained soil are attributed to their unique surface charge properties and specific surface area. The temporal variations in soil behavior, to some extent, can be credited to the changes in these properties. Among the multitude of factors that affect the charge and surface area of clay minerals, the inherent system chemistry occupies the cardinal position. The impact is more profound when the chemistry change is manifested in terms of the system pH. pH plays a significant role by modifying the edge charges of clay minerals and facilitating mineral dissolution. Hence there is a need to address the variations in physical and charge properties of fine-grained soils treated over a range of acidic as well as alkaline conditions. In the present study, three soils (two soils commercially procured and one natural soil) exhibiting distinct mineralogical compositions are subjected to different pH environment over a range of 2 to 13. The soil-solutions prepared at a definite liquid to solid ratio are adjusted to the required pH value by adding measured quantities of 0.1M HCl/0.1M NaOH. The studies are conducted over a range of interaction time, varying from 1 to 96 hours. The treated soils are then analyzed for their physical properties in terms of specific surface area and particle size characteristics. Further, modifications in surface morphology are evaluated from scanning electron microscope (SEM) imaging. Changes in the surface charge properties are assessed in terms of zeta potential measurements. Studies show significant variations in total surface area, probably because of the dissolution of clay minerals. This observation is further substantiated by the morphological analysis with SEM imaging. The zeta potential measurements on soils indicate noticeable variation upon pH treatment, which is partially ascribed to the modifications in the pH-dependant edge charges and partially due to the clay mineral dissolution. The results provide valuable insight into the role of pH in a clay-electrolyte system upon surface related phenomena such as species adsorption, fabric modification etc.

Keywords: acid and alkali treatment, mineral dissolution , specific surface area, zeta potential

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Authors: Mosima M. Mabitsela

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Groundnut is preferably grown on light textured soils. Most of these light textured soils tend to be highly weathered and characterized by high soil acidity and low nutrient status. One major soil factor associated with infertility of acidic soils that can negatively depress groundnut yield is aluminium (Al) toxicity. In plants Al toxicity damages root cells, leading to inhibition of root growth as a result of the suppression of cell division, cell elongation and cell expansion in the apical meristem cells of the root. The end result is that roots become stunted and brittle, root hair development is poor, and the root apices become swollen. This study was conducted to determine the effects of aluminium (Al) toxicity on a range of groundnut varieties. Fifteen cultivars were tested in incremental aluminum (Al) supply in an ebb and flow solution culture laid out in a randomized complete block design. There were six aluminium (Al) treatments viz. 0 µM, 1 µM, 5.7 µM, 14.14 µM, 53.18 µM, and 200 µM. At 1 µM there was no inhibitory effect on the growth of groundnut. The inhibition of groundnut growth was noticeable from 5.7 µM to 200 µM, where the severe effect of aluminium (Al) stress was observed at 200 µM. The cultivars varied in their response to aluminium (Al) supply in solution culture. Groundnuts are one of the most important food crops in the world, and its supply is on a decline due to the light-textured soils that they thrive under as these soils are acidic and can easily solubilize aluminium (Al) to its toxic form. Consequently, there is a need to develop groundnut cultivars with high tolerance to soil acidity.

Keywords: aluminium toxicity, cultivars, reduction, root growth

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Authors: Abiola Ayopo Abiodun, Zalihe Nalbantoglu

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The electrokinetic application (EKA), a relatively modern chemical treatment has a potential for in-situ ground improvement in an open field or under existing structures. It utilizes a low electrical gradient to transport electrolytic chemical ions between bespoke electrodes inserted in the fine-grained, low permeable soft soils. The paper investigates the efficacy of the EKA as a mitigation technique for the soft clay beds. The laboratory model of the EKA comprises of rectangular plexiglass test tank, electrolytes compartments, geosynthetic electrodes and direct electric current supply. Within this setup, the EK effects resulted from the exchange of ions between anolyte (anodic) and catholyte (cathodic) ends through the tested soil were examined by basic experimental laboratory testing methods. As such, the treated soft soil properties were investigated as a function of the anode-to-cathode distances and curing periods. The test results showed that there have been some changes in the physical and engineering properties of the treated soft soils. The significant changes in the physicochemical and electrical properties suggested that their corresponding changes can be utilized as a monitoring technique to evaluate the improvement in the engineering properties EK treated soft clay soils.

Keywords: electrokinetic, electrolytes, exchange ions, geosynthetic electrodes, soft soils

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Authors: Lahcen Daoudi, Soukaina Elidrissi, Nathalie Fagel

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The calcareous accumulations in the surface formations of the soil, are a very widespread phenomenon in the arid and semi-arid regions. Many aspects of physical and chemical evolution of these soils were debated for more than one century. The last two decades have witnessed a remarkable interest in the study of the calcrete. In Morocco, as in most Mediterranean countries, soils with carbonate accumulation cover large areas of the territory. The isohumic subtropical soils and red Mediterranean soils include always a horizon of calcrete accumulation. In the lowland of Tensift Al Haouz located in the central part of Morocco, the arable lands are underlain by indurate pedogenic calcrete of various thicknesses; this constitutes a serious handicap for agricultural development in the region. Our aims in this study is to analyze the characteristics of the crusts developed in this area in order to identify the various facies, their geographic distribution and the factors that played a significant role in the differentiation of these calcareous accumulations. The characterizations were based on various techniques including field observations, X-ray diffraction analysis (XRD) for both raw materials and clay fractions, SEM analysis, Calcimetry and Loss On Ignition (LOI). The analysis of encrusting calcrete in a rich and varied observation field as the region of Tensift Al Haouz enabled us to specify the important types of accumulations: diffuse, nodular and massive encrusting. The shape of encrusting as well as their consistency and hardness is clearly related to the contents of CaCO3 of the profiles. Among these facies, the hardpan which results from a complex succession of processes is certainly the most morphologically advanced form of encrusting. The vertical and lateral distribution of these forms in the Tensift Al Haouz area indicates that they do not appear randomly but seem related to well defined environmental conditions. The differentiation and evolution of encrusting is under the influence of two major factors: 1) the availability of carbonate rich solution which is controlled by the topography, the nature and texture of underlying host rock and the detrital processes; 2) the climate which is responsible for the evaporation and crystallization of carbonate.

Keywords: soil calcrete, characterization, morphology, Tensift Al Haouz, Morocco

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Authors: Sung-Sik Park, Han Chang, Kyung-Hun Chae, Sae-Byeok Lee

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In this study, a three-dimensional (3D) Particle method without using grid was developed for analyzing large deformation of soils instead of using ordinary finite element method (FEM) or finite difference method (FDM). In the 3D Particle method, the governing equations were discretized by various particle interaction models corresponding to differential operators such as gradient, divergence, and Laplacian. The Mohr-Coulomb failure criterion was incorporated into the 3D Particle method to determine soil failure. The yielding and hardening behavior of soil before failure was also considered by varying viscosity of soil. First of all, an unconfined compression test was carried out and the large deformation following soil yielding or failure was simulated by the developed 3D Particle method. The results were also compared with those of a commercial FEM software PLAXIS 3D. The developed 3D Particle method was able to simulate the 3D large deformation of soils due to soil yielding and calculate the variation of normal and shear stresses following clay deformation.

Keywords: particle method, large deformation, soil column, confined compressive stress

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Authors: Mohamed Fadzlee Sulaiman, Mohd Zabri Adil Talib, Aswami Fadillah Mohd Ariffin

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Each individual organization has their own mechanism to build up cyber defense capability in protecting their information infrastructures from data breaches and cyber espionage. But, we can not deny the possibility of failing to detect and stop cyber attacks especially for those targeting credential information and intellectual property (IP). In this paper, we would like to share the modern approach of effective digital forensic methodology in order to identify the artifacts in tracing the trails of evidence while mitigating the infection from the target machine/s. This proposed approach will suit the digital forensic investigation to be conducted while resuming the business critical operation after mitigating the infection and minimizing the risk from the identified attack to transpire. Therefore, traditional digital forensics methodology has to be improvised to be proactive which not only focusing to discover the root caused and the threat actor but to develop the relevant mitigation plan in order to prevent from the same attack.

Keywords: digital forensic, detection, eradication, targeted attack, malware

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Authors: Harsha B. R., K. S. Anil Kumar

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Land characterization, classification, and soil suitability evaluation of grapes-growing pedons were assessed at fifteen taluks covering four agro climatic zones of Karnataka. Study on problems and potentials of grapes cultivation in selected agro-climatic zones was carried out along with the plant sample analysis. Twenty soil profiles were excavated as study site based on the dominance of area falling under grapes production and existing spatial variability of soils. The detailed information of profiles and horizon wise soil samples were collected to study the morphological, physical, chemical, and fertility characteristics. Climatic analysis and water retention characteristics of soils of major grapes-growing areas were also done. Based on the characterisation and classification study, it was revealed that soils of Doddaballapur (Bangalore Blue and Wine grapes), Bangalore North (GKVK Farm, Rajankunte, and IIHR Farm), Devanahalli, Magadi, Hoskote, Chikkaballapur (Dilkush and Red globe), Yelaburga, Hagari Bommanahalli, Bagalkot (UHS farm) and Indi fall under the soil order Alfisol. Vijaypur pedon of northern dry zone was keyed out as Vertisols whereas, Jamkhandi and Athani as Inceptisols. Properties of Aridisols were observed in B. Bagewadi (Manikchaman and Thompson Seedless) and Afzalpur. Soil fertility status and its mapping using GIS technique revealed that all the nutrients were found to be in adequate range except nitrogen, potassium, zinc, iron, and boron, which indicated the need for application along with organic matter to improve the SOC status. Varieties differed among themselves in yield and plant nutrient composition depending on their age, climatic, soil, and management requirements. Bangalore North (GKVK farm) and Jamkhandi are having medium soil organic carbon stocks of 6.21 and 6.55 kg m⁻³, respectively. Soils of Bangalore North (Rajankunte) were highly suitable (S1) for grapes cultivation. Under northern Karnataka, Vijayapura, B. Bagewadi, Indi, and Afzalpur vineyards were good performers despite the limitations of fertility and free lime content.

Keywords: land characterization, suitability, soil orders, soil organic carbon stock

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Authors: Saeed Bagherifam, Trevor Brown, Chris Fellows, Ravi Naidu

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Over the last century, rapid urbanization, industrial emissions, and mining activities have resulted in widespread contamination of the environment by heavy metal(loid)s. Arsenic (As) is a toxic metalloid belonging to group 15 of the periodic table, which occurs naturally at low concentrations in soils and the earth’s crust, although concentrations can be significantly elevated in natural systems as a result of dispersion from anthropogenic sources, e.g., mining activities. Bioavailability is the fraction of a contaminant in soils that is available for uptake by plants, food chains, and humans and therefore presents the greatest risk to terrestrial ecosystems. Numerous attempts have been made to establish in situ and ex-situ technologies of remedial action for remediation of arsenic-contaminated soils. In situ stabilization techniques are based on deactivation or chemical immobilization of metalloid(s) in soil by means of soil amendments, which consequently reduce the bioavailability (for biota) and bioaccessibility (for humans) of metalloids due to the formation of low-solubility products or precipitates. This study investigated the effectiveness of two different types of synthetic manganese and iron oxides (birnessite and goethite) for stabilization of As in a soil spiked with 1000 mg kg⁻¹ of As and treated with 10% dosages of soil amendments. Birnessite was made using HCl and KMnO₄, and goethite was synthesized by the dropwise addition of KOH into Fe(NO₃) solution. The resulting contaminated soils were subjected to a series of chemical extraction studies including sequential extraction (BCR method), single-step extraction with distilled (DI) water, 2M HNO₃ and simplified bioaccessibility extraction tests (SBET) for estimation of bioaccessible fractions of As in two different soil fractions ( < 250 µm and < 2 mm). Concentrations of As in samples were measured using inductively coupled plasma mass spectrometry (ICP-MS). The results showed that soil with birnessite reduced bioaccessibility of As by up to 92% in both soil fractions. Furthermore, the results of single-step extractions revealed that the application of both birnessite and Goethite reduced DI water and HNO₃ extractable amounts of arsenic by 75, 75, 91, and 57%, respectively. Moreover, the results of the sequential extraction studies showed that both birnessite and goethite dramatically reduced the exchangeable fraction of As in soils. However, the amounts of recalcitrant fractions were higher in birnessite, and Goethite amended soils. The results revealed that the application of both birnessite and goethite significantly reduced bioavailability and the exchangeable fraction of As in contaminated soils, and therefore birnessite and Goethite amendments might be considered as promising adsorbents for stabilization and remediation of As contaminated soils.

Keywords: arsenic, bioavailability, in situ stabilisation, metalloid(s) contaminated soils

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Authors: Kwestan Salimi, Jenna Jacoby, Michelle Basham, Amy Cerato

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The extreme annual weather patterns of the central United States have increased the need for underground shelters for protection from destructive tornadic activity. However, very few residential homes have basements due to the added construction expense and the prevalence of expansive soils covering the central portion of the United States. These expansive soils shrink and swell, increasing earth pressure on basement walls. To mitigate the effect of expansive soils on basement walls, this study performed bench-scale tests using a common natural expansive soil mitigated with a backfill layer of crumb rubber. The results revealed that at 80% soil compaction, a 1:6 backfill height to total height ratio produced a 66% reduction in swell pressure. However, this percent reduction decreased to 27% for 90% soil compaction. It was also found that there is a strong linear correlation between compaction percentage and reduction in swell pressure when using the same backfill height to total height ratio. Using this correlation and extrapolating to 95% compaction, the percent reduction in swell pressure was approximately 12%.

Keywords: expansive soils, swell/shrink, swell pressure, stabilization, crumb rubber

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Authors: Shirin jalili, Hadi Shirzad, Mahasti Modarresi, Samaneh Nabavi, Somayeh Khanjani

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Identifying the source tissue of biological material found at crime scenes can be very informative in a number of cases. Despite their usefulness, current visual, catalytic, enzymatic, and immunologic tests for presumptive and confirmatory tissue identification are applicable only to a subset of samples, might suffer limitations such as low specificity, lack of sensitivity, and are substantially impacted by environmental insults. In addition their results are operator-dependent. Recently the possibility of discriminating body fluids using mRNA expression differences in tissues has been described but lack of long term stability of that Molecule and the need to normalize samples for each individual are limiting factors. The use of DNA should solve these issues because of its long term stability and specificity to each body fluid. Cells in the human body have a unique epigenome, which includes differences in DNA methylation in the promoter of genes. DNA methylation, which occurs at the 5′-position of the cytosine in CpG dinucleotides, has great potential for forensic identification of body fluids, because tissue-specific patterns of DNA methylation have been demonstrated, and DNA is less prone to degradation than proteins or RNA. Previous studies have reported several body fluid-specific DNA methylation markers.The presence or absence of a methyl group on the 5’ carbon of the cytosine pyridine ring in CpG dinucleotide regions called ‘CpG islands’ dictates whether the gene is expressed or silenced in the particular body fluid. Were described methylation patterns at tissue specific differentially methylated regions (tDMRs) to be stable and specific, making them excellent markers for tissue identification. The results demonstrate that methylation-based tissue identification is more than a proof-of-concept. The methodology holds promise as another viable forensic DNA analysis tool for characterization of biological materials.

Keywords: DNA methylation, forensic science, epigenome, tDMRs

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Authors: Millicent N. Khumalo, Phesheya E. Dlamini

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Shrub-encroachment leads to a gain or loss of soil organic carbon (SOC) in previously open rangelands. The stabilization mechanisms controlling the storage of soil organic carbon (SOC) within aggregates of shrub-encroached grassland soils are poorly understood, especially in shallow plinthic soils. In this study, physical fractionation of surface soils (0- 10 cm) collected from open and shrub-encroached grasslands was conducted to determine the distribution of SOC within macro-and- microaggregates. Soil aggregates were classified into four fractions by a wet-sieving procedure, namely >2000 (large macro-aggregates), 212-2000 (small macro-aggregates), 50-212 (microaggregates) and < 50µm (silt+clay). In both shrub-encroached and open grassland soils, SOC was greater in the silt+clay fraction. In this fraction, SOC was on average 133% greater in shrub-encroached compared to open grassland. The greater SOC within the silt+clay fraction is due to the greater surface area and thus more exchange sites for carbon absorption. This implies that the SOC physically protected within the silt+clay is stored long-term.

Keywords: aggregate fractions, shrub-encroachment, soil organic carbon, stabilization

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Authors: Violina Angelova, Mariana Perifanova-Nemska, Krasimir Ivanov

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The aim of this research was to investigate the potential for the use of Ricinus communis L. (castor oil plant) to remediate metal-polluted sites. This study was performed in industrially polluted soils containing high concentrations of Zn, Pb and Cd, situated at different distances (0.3, 2.0 and 15.0 km) from the source of pollution - the Non-Ferrous Metal Works near Plovdiv, Bulgaria. On reaching commercial ripeness, the castor oil plants were gathered and the contents of heavy metals in their different parts – roots, stems, leaves and seeds, were determined after dry ashing. Physico-chemical characterization, total, DTPA extractable and water-soluble metals in rhizospheric soil samples were carried. Translocation factors (TFs) were also determined. The quantitative measurements were carried out with ICP. A soxhlet extraction was used for the extraction of the oil, using hexane as solvent. The oil was recovered by simple distillation of the solvent. The residual oil obtained was investigated for physicochemical parameters and fatty acid composition. Bioaccumulation factor and translocation factor values (BAF and TF > 1) were greater than one suggesting efficient accumulation in the shoot. The castor oil plant may be preferred as a good candidate for phytoremediation (phytoextraction). These results indicate that R. communis has good potential for removing Pb from contaminated soils attributed to its fast growth, high biomass, strong absorption and accumulation for Pb. The concentrations of heavy metals in the oil were low as seed coats accumulated the highest concentrations of Cd and Pb. In addition, the result of the fatty acid composition analysis confirms the oil to be of good quality and can be used for industrial purposes such as cosmetics, soaps and paint.

Keywords: castor bean, heavy metals, phytoremediation, polluted soils

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Authors: Sedat Aktas, Egemen Ulusoy, Remzi Yildirim

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This article explains how to get a ram image from a computer with a Linux operating system and what steps should be followed while getting it. What we mean by taking a ram image is the process of dumping the physical memory instantly and writing it to a file. This process can be likened to taking a picture of everything in the computer’s memory at that moment. This process is very important for tools that analyze ram images. Volatility can be given as an example because before these tools can analyze ram, images must be taken. These tools are used extensively in the forensic world. Forensic, on the other hand, is a set of processes for digitally examining the information on any computer or server on behalf of official authorities. In this article, the protected mode architecture in the Linux operating system is examined, and the way to save the image sample of the kernel driver and system memory to disk is followed. Tables and access methods to be used in the operating system are examined based on the basic architecture of the operating system, and the most appropriate methods and application methods are transferred to the article. Since there is no article directly related to this study on Linux in the literature, it is aimed to contribute to the literature with this study on obtaining ram images. LIME can be mentioned as a similar tool, but there is no explanation about the memory dumping method of this tool. Considering the frequency of use of these tools, the contribution of the study in the field of forensic medicine has been the main motivation of the study due to the intense studies on ram image in the field of forensics.

Keywords: linux, paging, addressing, ram-image, memory dumping, kernel modules, forensic

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Authors: I. Ahumada, L. Ascar, C. Pedraza, J. Montecino

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It has been found that the addition of biosolids to soil is beneficial to soil health, enriching soil with essential nutrient elements. Although this sludge has properties that allow for the improvement of the physical features and productivity of agricultural and forest soils and the recovery of degraded soils, they also contain trace elements, organic trace and pathogens that can cause damage to the environment. The application of these biosolids to land without the total reclamation and the treated wastewater can transfer these compounds into terrestrial and aquatic environments, giving rise to potential accumulation in plants. The general aim of this study was to evaluate the bioavailability of bisphenol A (BPA), and 17 α-ethynyl estradiol (EE2) in a soil-biosolid system using wheat (Triticum aestivum) plant assays and a predictive extraction method using a solution of hydroxypropyl-β-cyclodextrin (HPCD) to determine if it is a reliable surrogate for this bioassay. Two soils were obtained from the central region of Chile (Lo Prado and Chicauma). Biosolids were obtained from a regional wastewater treatment plant. The soils were amended with biosolids at 90 Mg ha-1. Soils treated with biosolids, spiked with 10 mgkg-1 of the EE2 and 15 mgkg-1 and 30 mgkg-1of BPA were also included. The BPA, and EE2 concentration were determined in biosolids, soils and plant samples through ultrasound assisted extraction, solid phase extraction (SPE) and gas chromatography coupled to mass spectrometry determination (GC/MS). The bioavailable fraction found of each one of soils cultivated with wheat plants was compared with results obtained through a cyclodextrin biosimulator method. The total concentration found in biosolid from a treatment plant was 0.150 ± 0.064 mgkg-1 and 12.8±2.9 mgkg-1 of EE2 and BPA respectively. BPA and EE2 bioavailability is affected by the organic matter content and the physical and chemical properties of the soil. The bioavailability response of both compounds in the two soils varied with the EE2 and BPA concentration. It was observed in the case of EE2, the bioavailability in wheat plant crops contained higher concentrations in the roots than in the shoots. The concentration of EE2 increased with increasing biosolids rate. On the other hand, for BPA, a higher concentration was found in the shoot than the roots of the plants. The predictive capability the HPCD extraction was assessed using a simple linear correlation test, for both compounds in wheat plants. The correlation coefficients for the EE2 obtained from the HPCD extraction with those obtained from the wheat plants were r= 0.99 and p-value ≤ 0.05. On the other hand, in the case of BPA a correlation was not found. Therefore, the methodology was validated with respect to wheat plants bioassays, only in the EE2 case. Acknowledgments: The authors thank FONDECYT 1150502.

Keywords: emerging compounds, bioavailability, biosolids, endocrine disruptors

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Authors: A. Cerrato Casado, C. Guigou, P. Jean

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In this investigation, the particle swarm optimization (PSO) algorithm is used to perform the inversion of the dispersion curves in the spectral analysis of surface waves (SASW) method. This inverse problem usually presents complicated solution spaces with many local minima that make difficult the convergence to the correct solution. PSO is a metaheuristic method that was originally designed to simulate social behavior but has demonstrated powerful capabilities to solve inverse problems with complex space solution and a high number of variables. The dispersion curve of the synthetic soils is constructed by the vertical flexibility coefficient method, which is especially convenient for soils where the stiffness does not increase gradually with depth. The reason is that these types of soil profiles are not normally dispersive since the dominant mode of Rayleigh waves is usually not coincident with the fundamental mode. Multiple synthetic soil profiles have been tested to show the characteristics of the convergence process and assess the accuracy of the final soil profile. In addition, the inversion procedure is applied to multiple real soils and the final profile compared with the available information. The combination of the vertical flexibility coefficient method to obtain the dispersion curve and the PSO algorithm to carry out the inversion process proves to be a robust procedure that is able to provide good solutions for complex soil profiles even with scarce prior information.

Keywords: dispersion, inverse problem, particle swarm optimization, SASW, soil profile

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Authors: Sawangjit Sopid

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In this study sugarcane field soils with a long history of atrazine application in Chachoengsao and Chonburi provinces have been explored for their potential of atrazine biodegradation. For the atrazine degrading bacteria isolation, the soils used in this study named ACS and ACB were inoculated in MS-medium containing atrazine. Six short rod and gram-negative bacterial isolates, which were able to use this herbicide as a sole source of nitrogen, were isolated and named as ACS1, ACB1, ACB3, ACB4, ACB5 and ACB6. From the 16S rDNA nucleotide sequence analysis, the isolated bacteria ACS1 and ACB4 were identified as Rhizobium sp. with 89.1-98.7% nucleotide identity, ACB1 and ACB5 were identified as Stenotrophomonas sp. with 91.0-92.8% nucleotide identity, whereas ACB3 and ACB6 were Klebsiella sp. with 97.4-97.8% nucleotide identity.

Keywords: atrazine-degrading bacteria, bioremediation, Thai isolates, bacteria

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Authors: Sunday Nathaniel Obasi, Chiamak Chinasa Obasi

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Soil characterization and classification provide the basic information necessary to create a functional evaluation and soil classification schemes. Fertility capability classification (FCC) on the other hand is a technical system that groups the soils according to kinds of problems they present for management of soil physical and chemical properties. This research was carried out in Ebonyi state, southeastern Nigeria, which is an agrarian state and a leading rice producing part of southeastern Nigeria. In order to maximize the soil and enhance the productivity of rice in Ebonyi soils, soil classification, and fertility classification information need to be supplied. The state was grouped into three locations according to their agricultural zones namely; Ebonyi north, Ebonyi central and Ebonyi south representing Abakaliki, Ikwo and Ivo locations respectively. Major rice growing areas of the soils were located and two profile pits were sunk in each of the studied zones from which soils were characterized, classified and fertility capability classification (FCC) developed. Soil classification was done using United State Department of Agriculture (USDA) Soil Taxonomy and correlated with World Reference Base for soil resources. Results obtained classified Abakaliki 1 and Abakaliki 2 as Typic Fluvaquents (Ochric Fluvisols). Ikwo 1 was classified as Vertic Eutrudepts (Eutric Vertisols) while Ikwo 2 was classified as Typic Eutrudepts (Eutric Cambisols). Ivo 1 and Ivo 2 were both classified as Aquic Eutrudepts (Gleyic Leptosols). Fertility capability classification (FCC) revealed that all studied soils had mostly loamy topsoils and subsoils except Ikwo 1 with clayey topsoil. Limitations encountered in the studied soils include; dryness (d), low ECEC (e), low nutrient capital reserve (k) and water logging/ anaerobic condition (gley). Thus, FCC classifications were Ldek for Abakaliki 1 and 2, Ckv for Ikwo 1, LCk for Ikwo 2 while Ivo 1 and 2 were Legk and Lgk respectively.

Keywords: soil classification, soil fertility, limitations, modifiers, Southeastern Nigeria

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Authors: N. S. Aggangan, B. Dell, P. Jeffries

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Two moderately nickel-tolerant isolates of Pisolithus were compared with a non-Ni tolerant isolate for the ability to increase the growth of Eucalyptus urophylla seedlings in the presence of nickel (Ni) in pots in a glasshouse. Seedlings, either inoculated with mycorrhizal fungi or uninoculated, were transplanted into pots containing 3 kg steam-pasteurized yellow sand amended with five concentrations of nickel (0, 6, 12, 24 and 48 mg Ni kg-1 soil). Within a day after transplanting, all seedlings subjected to Ni rates greater than 12 mg Ni kg-1 showed symptoms of wilting and all died within two weeks. At lower nickel concentrations, inoculation with all 3 Pisolithus strains increased rates of seedling survival after 12 weeks. Inoculation with all 3 isolates Pisolithus significantly increased the growth of plants in Ni-free soils between 2 to 4 fold dependent on isolate. However, seedlings growing in soils containing 12 mg Ni kg-1 grew poorly, mycorrhizal development was inhibited and no beneficial effects of inoculation were noted. In contrast, in soils containing 6mg Ni kg-1, inoculated seedlings did not show the reduced root growth and severe toxicity symptoms (chlorosis on young leaves and shoot tips) of uninoculated seedlings. Only the Ni-tolerant Pisolithus strains conferred a significant growth benefit compared to non-inoculated controls, and plants inoculated with one of these strains grew twice the size as those inoculated with the other Ni-tolerant strain. Inorganic plant analysis revealed that inoculation increased plant growth through improved P uptake but did not prevent Ni uptake. However, toxicity may have been minimized by dilution due to an increase in plant biomass. The results suggest that only one of the Ni-tolerant strains of Pisolithus has the potential to improve the growth and survival of E. urophylla seedlings in serpentine soils in the Philippines.

Keywords: ectomycorrhizas, Eucalyptus urophylla, nickel tolerance, pisolithus

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Authors: Issam Aouari, Abdelmalek Abdelhamid

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For seismologists, the characterization of seismic demand should include the amplitude and duration of strong shaking in the system. The duration of ground shaking is one of the key parameters in earthquake resistant design of structures. This paper proposes a nonlinear statistical model to estimate earthquake ground motion duration in soft soils using multiple seismicity indicators. Three definitions of ground motion duration proposed by literature have been applied. With a comparative study, we select the most significant definition to use for predict the duration. A stochastic model is presented for the McCann and Shah Method using nonlinear regression analysis based on a data set for moment magnitude, source to site distance and site conditions. The data set applied is taken from PEER strong motion databank and contains shallow earthquakes from different regions in the world; America, Turkey, London, China, Italy, Chili, Mexico...etc. Main emphasis is placed on soft site condition. The predictive relationship has been developed based on 600 records and three input indicators. Results have been compared with others published models. It has been found that the proposed model can predict earthquake ground motion duration in soft soils for different regions and sites conditions.

Keywords: duration, earthquake, prediction, regression, soft soil

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Authors: Vesna Karapetkovska Hristova, M. Ayaz Ahmad, Julijana Tomovska, Biljana Bogdanova Popov, Blagojce Najdovski

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The average total concentrations of heavy metals; (cadmium [Cd], copper [Cu], nickel [Ni], lead [Pb], and zinc [Zn]) were analyzed in soil and vegetables samples collected from the different region of Macedonia during the years 2010-2012. Basic soil properties such as pH, organic matter and clay content were also included in the study. The average concentrations of Cd, Cu, Ni, Pb, Zn in the A horizon (0-30 cm) of agricultural soils were as follows, respectively: 0.25, 5.3, 6.9, 15.2, 26.3 mg kg-1 of soil. We have found that neural networking model can be considered as a tool for prediction and spatial analysis of the processes controlling the metal transfer within the soil-and vegetables. The predictive ability of such models is well over 80% as compared to 20% for typical regression models. A radial basic function network reflects good predicting accuracy and correlation coefficients between soil properties and metal content in vegetables much better than the back-propagation method. Neural Networking / soft computing can support the decision-making processes at different levels, including agro ecology, to improve crop management based on monitoring data and risk assessment of metal transfer from soils to vegetables.

Keywords: soft computing approach, total concentrations, heavy metals, agricultural soils

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Authors: Mozhgan Farzami Sepehr, Farhad Nourozi

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In a greenhouse study, decontamination capacity of the species Polypogon monspoliensis, for detoxification of petroleum-polluted soils caused by sewage and waste materials of Tehran Petroleum Refinery. For this purpose, the amount of total oil and grease before and 45 days after transplanting one-month-old seedlings in the soils of five different treatments in which pollution-free agricultural soil and contaminated soil were mixed together with the weight ratio of respectively 1 to 9 (% 10), 2 to 8 (%20), 3 to 7 (%30) , 4 to 6 (%40), and 5 to 5 (%50) were evaluated and compared with the amounts obtained from control treatment without vegetation, but with the same concentration of pollution. Findings demonstrated that the maximum reduction in the petroleum rate ,as much as 84.85 percent, is related to the treatment 10% containing the plant. Increasing the shoot height in treatments 10% and 20% as well as the root dry and fresh weight in treatments 10% , 20% , and 30% shows that probably activity of more rhizosphere microorganisms of the plant in these treatments has led to the improvement in growth of plant organs comparing to the treatments without pollution.

Keywords: phytoremediation, total oil and grease, rhizosphere, microorganisms, petroleum-contaminated soil

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Authors: Surbhi Mathur, J. M. Vyas

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Although the rapid development of forensic speaker recognition technology has been conducted, there are still many problems to be solved. The biggest problem arises when the cases involving disguised voice samples come across for the purpose of examination and identification. Such type of voice samples of anonymous callers is frequently encountered in crimes involving kidnapping, blackmailing, hoax extortion and many more, where the speaker makes a deliberate effort to manipulate their natural voice in order to conceal their identity due to the fear of being caught. Voice disguise causes serious damage to the natural vocal parameters of the speakers and thus complicates the process of identification. The sole objective of this doctoral project is to find out the possibility of rendering definite opinions in cases involving disguised speech by experimentally determining the effects of different disguise forms on personal identification and percentage rate of speaker recognition for various voice disguise techniques such as raised pitch, lower pitch, increased nasality, covering the mouth, constricting tract, obstacle in mouth etc by analyzing and comparing the amount of phonetic and acoustic variation in of artificial (disguised) and natural sample of an individual, by auditory as well as spectrographic analysis.

Keywords: forensic, speaker recognition, voice, speech, disguise, identification

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Authors: Hassan. A. Abas, Saad A. Aiban

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Soil improvement by means of stone column method is used to improve sabkha soils in order to limit total and differential settlement and to achieve the required bearing capacity. Full-scale plate test was performed on site to confirm the achievement of required bearing capacity at the specified settlement. Despite the fact that this technique is widely used to improve sabkha soils, there are no studies focusing on the behavior of stone columns in such problematic soils. Sabkha soils are known for its high compressibility, low strength and water sensitivity due to loss of salt cementation upon flooding during installation of stone columns. Numerical modeling of plate load test assist to understand complicated behavior of sabkha – stone column interaction. This paper presents a three-dimensional Finite element model, using PLAXIS 3D software, to simulate vertical plate load tests on a stone column installed in sabkha. The predicted settlement values are in reasonable agreement with the field measure values and the field load - settlement curve can be predicted with good accuracy.

Keywords: soil improvement, stone column, sabkha, PLAXIS 3D

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Authors: Miseri Roeslan Afany, Nur Ainun Pulungan

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The unique characteristics of Andisol differentiate them from other soils. These characteristics become a guideline in determining management and usage with regards to agriculture. Especially in the tropical area, Andisols may have fast mineral alteration due to intensive water movement in the soils. Four soil chemical tests were conducted for evaluating soils in the study area. Al/Fe humus, allophane, pH, and P retention were used to differentiate Andisols under different practices. Non-cultivation practice (e.g. natural forest) and cultivation practices (e.g. horticulture systems and intensive farming systems) are compared in this study. We applied Blackmore method for P retention analysis. The aims of this study are: (i) to analyze the specific behavior of Al/Fe humus, pH, and allophane towards P retention in order (ii) to evaluate the effect of cultivation practices on their behavior changes among Andisols, and (iii) to gain the sustainable agriculture through proposing an appropriate soil managements in the study area. 5 observation sites were selected, and 75 soil sampling were analyzed in this study. The results show that the cultivation decreases P retention in all sampling sites. There is a declining from ±90% to ±50% of P retention in the natural forest where shifts into cultivated land. The average of P retention under 15 years of cultivation down into 63%, whereas, the average of P retention more than 15 years of cultivation down into 54%. Many factors affect the retention of P in the soil such as: (1) type and amount of clay, (2) allophone and/or imogolit, (3) Al/Fe humus, (4) soil pH, (5) type and amount of organic material, (6) Exchangeable bases (Ca, Mg, Na, K), (7) forms and solubility of Al/Fe. To achieve the sustainable agriculture in the study area, conventional agriculture practices should be preserved and intensive fertilizing practices should be applied in order to increase the soil pH, to maintain the organic matter of andisols, to maintain microba activities, and to release Al/Fe humus complex, and thus increase available P in the soils.

Keywords: Andisols, cultivation, P retention, sustainable agriculture

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Authors: Ajay Kumar Rana

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Predicting human behaviour, discerning monozygotic twins or left over remnant tissues/fluids of a single human source remains a big challenge in forensic science. Recent advances in the field of DNA methylations which are broadly chemical hallmarks in response to environmental factors can certainly help to identify and discriminate various single-source DNA samples collected from the crime scenes. In this review, cytosine methylation of DNA has been methodologically discussed with its broad applications in many challenging forensic issues like body fluid identification, race/ethnicity identification, monozygotic twins dilemma, addiction or behavioural prediction, age prediction, or even authenticity of the human DNA. With the advent of next-generation sequencing techniques, blooming of DNA methylation datasets and together with standard molecular protocols, the prospect of investigating and solving the above issues and extracting the exact nature of the truth for reconstructing the crime scene events would be undoubtedly helpful in defending and solving the critical crime cases.

Keywords: DNA methylation, differentially methylated regions, human identification, forensics

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Authors: Yan Wang, Guowei Chen, Gang Wang

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Soil microbial diversity is one of the important parameters to assess the soil fertility and soil health, even stability of the ecosystem. In this paper, we aim to reveal the soil microbial difference in rhizosphere and root zone, even to pick the special biomarkers influenced by the long term tillage practices, which included four treatments of no-tillage, ridge tillage, continuous cropping with corn and crop rotation with corn and soybean. Here, high-throughput sequencing was performed to investigate the difference of bacteria in rhizosphere and root zone. The results showed a very significant difference of species richness between rhizosphere and root zone soil at the same crop rotation system (p < 0.01), and also significant difference of species richness was found between continuous cropping with corn and corn-soybean rotation treatment in the rhizosphere statement, no-tillage and ridge tillage in root zone soils. Implied by further beta diversity analysis, both tillage methods and crop rotation systems influence the soil microbial diversity and community structure in varying degree. The composition and community structure of microbes in rhizosphere and root zone soils were clustered distinctly by the beta diversity (p < 0.05). Linear discriminant analysis coupled with effect size (LEfSe) analysis of total taxa in rhizosphere picked more than 100 bacterial taxa, which were significantly more abundant than that in root zone soils, whereas the number of biomarkers was lower between the continuous cropping with corn and crop rotation treatment, the same pattern was found at no-tillage and ridge tillage treatment. Bacterial communities were greatly influenced by main environmental factors in large scale, which is the result of biological adaptation and acclimation, hence it is beneficial for optimizing agricultural practices.

Keywords: tillage methods, biomarker, biodiversity, rhizosphere

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Authors: Rebone E. Mashapa, Phesheya E. Dlamini, Sandile S. Mthimkhulu

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Woody plant encroachment, a land cover transformation that reduces grassland productivity may influence soil physical properties. The objective of the study was to determine the effect of woody plant encroachment on physical properties of vertic soils in a savanna grassland. In this study, we quantified and compared soil bulk density, aggregate stability and porosity in the top and subsoil of an open and woody encroached savanna grassland. The results revealed that soil bulk density increases, while porosity and mean weight diameter decreases with depth in both open and woody encroached grassland soil. Compared to open grassland, soil bulk density was 11% and 10% greater in the topsoil and subsoil, while porosity was 6% and 9% lower in the topsoil and subsoil of woody encroached grassland. Mean weight diameter, an indicator of soil aggregation increased by 38% only in the subsoil of encroached grasslands due to increasing clay content with depth. These results suggest that woody plant encroachment leads to compaction of vertic soils, which in turn reduces pore size distribution.

Keywords: soil depth, soil physical properties, vertic soils, woody plant encroachment

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