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I M Kenawy, M A Ismail, M A H Hafez, M A Hashem
The new ion-imprinted guanyl-modified cellulose (II.Gu-MC) was prepared for the separation and determination of Cu (II) ions in different real samples. Several techniques such as Fourier Transform Infrared (FT-IR), scanning electron microscope (SEM), thermal analysis, potentiograph and elemental analysis have been utilized for the characterization of II.Gu-MC. The adsorption behavior of the ion imprinted polymer (II.Gu-MC) was evaluated and compared to the non ion-imprinted polymer (NII.Gu-MC) at the optimum conditions...
April 20, 2018: International Journal of Biological Macromolecules
Jacques Précigout, Holger Stünitz, Yves Pinquier, Rémi Champallier, Alexandre Schubnel
In order to address geological processes at great depths, rock deformation should ideally be tested at high pressure (> 0.5 GPa) and high temperature (> 300 °C). However, because of the low stress resolution of current solid-pressure-medium apparatuses, high-resolution measurements are today restricted to low-pressure deformation experiments in the gas-pressure-medium apparatus. A new generation of solid-medium piston-cylinder ("Griggs-type") apparatus is here described. Able to perform high-pressure deformation experiments up to 5 GPa and designed to adapt an internal load cell, such a new apparatus offers the potential to establish a technological basis for high-pressure rheology...
April 3, 2018: Journal of Visualized Experiments: JoVE
Gilad Antler, André Pellerin
Separating the contributions of anaerobic oxidation of methane and organoclastic sulfate reduction in the overall sedimentary sulfur cycle of marine sediments has benefited from advances in isotope biogeochemistry. Particularly, the coupling of sulfur and oxygen isotopes measured in the residual sulfate pool (δ18 OSO4 vs. δ34 SSO4 ). Yet, some important questions remain. Recent works have observed patterns that are inconsistent with previous interpretations. We differentiate the contributions of oxygen and sulfur isotopes to separating the anaerobic oxidation of methane and organoclastic sulfate reduction into three phases; first evidence from conventional high methane vs...
2018: Frontiers in Microbiology
Xingang Li, Jia Li, Hong Sui, Lin He, Xingtao Cao, Yonghong Li
Soil remediation has been considered as one of the most difficult pollution treatment tasks due to its high complexity in contaminants, geological conditions, usage, urgency, etc. The diversity in remediation technologies further makes quick selection of suitable remediation schemes much tougher even the site investigation has been done. Herein, a sustainable decision support hierarchical model has been developed to select, evaluate and determine preferred soil remediation schemes comprehensively based on modified analytic hierarchy process (MAHP)...
April 6, 2018: Journal of Hazardous Materials
Perry G Beasley-Hall, Simon M Tierney, Phillip Weinstein, Andrew D Austin
Australian cave crickets are members of the subfamily Macropathinae (Orthoptera: Rhaphidophoridae). The subfamily is thought to have originated prior to the tectonic separation of the supercontinent Gondwana based on distributions of extant lineages and molecular phylogenetic evidence, although the Australian fauna have been underrepresented in previous studies. The current study augments existing multigene data (using 12S, 16S, and 28S rRNA genes) to investigate the placement of the Australian representatives within the Macropathinae and to assess divergence dates of select clades...
April 17, 2018: Molecular Phylogenetics and Evolution
Rosa Gabriela Beltrán-López, Omar Domínguez-Domínguez, Rodolfo Pérez-Rodríguez, Kyle Piller, Ignacio Doadrio
BACKGROUND: Volcanic and tectonic activities in conjunction with Quaternary climate are the main events that shaped the geographical distribution of genetic variation of many lineages. Poeciliopsis infans is the only poeciliid species that was able to colonize the temperate highlands of central Mexico. We inferred the phylogenetic relationships, biogeographic history, and historical demography in the widespread Neotropical species P. infans and correlated this with geological events and the Quaternary glacial-interglacial climate in the highlands of central Mexico, using the mitochondrial genes Cytochrome b and Cytochrome oxidase I and two nuclear loci, Rhodopsin and ribosomal protein S7...
April 20, 2018: BMC Evolutionary Biology
P M Myrow, M P Lamb, R C Ewing
Earth's most severe climate changes occurred during global-scale snowball-Earth glaciations, which profoundly altered Earth's atmosphere, oceans, and biosphere. Extreme rates of glacio-eustatic sea-level rise are a fundamental prediction of the snowball Earth hypothesis, but supporting geologic evidence is lacking. We use paleohydraulic analysis of wave ripples and tidal laminae of the Elatina Formation, Australia - deposited following the Marinoan glaciation ca. 635Ma - to show that water depths of 9-16m remained nearly constant for ~100yrs throughout 27m of sediment accumulation...
April 19, 2018: Science
Menghao Wu, Tianci Duan, Chengliang Lu, Huahua Fu, Shuai Dong, Junming Liu
Oxyhydroxide minerals such as FeOOH have been a research focus in geology for studying the Earth's interior, and also in chemistry for studying their oxygen electrocatalysis activity. In this paper the first-principle evidence of a new class of ferroelectrics/multiferroics is given. In this class are: β-CrOOH (guyanaite), ε-FeOOH, β-GaOOH, and InOOH, which are earth-abundant minerals which have been experimentally verified to possess distorted rutile structures, are ferroelectric with considerable polarizations (up to 24 μC cm-2) and piezoelectric coefficients...
April 19, 2018: Nanoscale
Tímea Novák-Szabó, András Árpád Sipos, Sam Shaw, Duccio Bertoni, Alessandro Pozzebon, Edoardo Grottoli, Giovanni Sarti, Paolo Ciavola, Gábor Domokos, Douglas J Jerolmack
River currents, wind, and waves drive bed-load transport, in which sediment particles collide with each other and Earth's surface. A generic consequence is impact attrition and rounding of particles as a result of chipping, often referred to in geological literature as abrasion. Recent studies have shown that the rounding of river pebbles can be modeled as diffusion of surface curvature, indicating that geometric aspects of impact attrition are insensitive to details of collisions and material properties. We present data from fluvial, aeolian, and coastal environments and laboratory experiments that suggest a common relation between circularity and mass attrition for particles transported as bed load...
March 2018: Science Advances
Elizabeth C Sklute, A Deanne Rogers, Jason C Gregerson, Heidi B Jensen, Richard J Reeder, M Darby Dyar
Salts with high hydration states have the potential to maintain high levels of relative humidity (RH) in the near subsurface of Mars, even at moderate temperatures. These conditions could promote deliquescence of lower hydrates of ferric sulfate, chlorides, and other salts. Previous work on deliquesced ferric sulfates has shown that when these materials undergo rapid dehydration, such as that which would occur upon exposure to present day Martian surface conditions, an amorphous phase forms. However, the fate of deliquesced halides or mixed ferric sulfate-bearing brines are presently unknown...
March 1, 2018: Icarus
Tiffany VanDerwerker, Lin Zhang, Erin Ling, Brian Benham, Madeline Schreiber
We investigated if geologic factors are linked to elevated arsenic (As) concentrations above 5 μg/L in well water in the state of Virginia, USA. Using geologic unit data mapped within GIS and two datasets of measured As concentrations in well water (one from public wells, the other from private wells), we evaluated occurrences of elevated As (above 5 μg/L) based on geologic unit. We also constructed a logistic regression model to examine statistical relationships between elevated As and geologic units...
April 18, 2018: International Journal of Environmental Research and Public Health
Jenan J Kharbush, Luke R Thompson, Mohamed Fauzi Haroon, Rob Knight, Lihini I Aluwihare
Hopanoids, including the extended side chain-containing bacteriohopanepolyols (BHPs), are bacterial lipids found abundantly in the geological record and across Earth's surface environments. However, the physiological roles of this biomarker remain uncertain, limiting interpretation of their presence in current and past environments. Recent work investigating the diversity and distribution of hopanoid producers in the marine environment implicated low-oxygen regions as important loci of hopanoid production, and data from marine oxygen minimum zones (OMZs) suggested that the dominant hopanoid producers in these environments are nitrite-utilizing organisms, revealing a potential connection between hopanoid production and the marine nitrogen cycle...
April 12, 2018: FEMS Microbiology Ecology
Matthew V Emery, Robert J Stark, Tyler J Murchie, Spencer Elford, Henry P Schwarcz, Tracy L Prowse
OBJECTIVES: We obtained the oxygen and strontium isotope composition of teeth from Roman period (1st to 4th century CE) inhabitants buried in the Vagnari cemetery (Southern Italy), and present the first strontium isotope variation map of the Italian peninsula using previously published data sets and new strontium data. We test the hypothesis that the Vagnari population was predominantly composed of local individuals, instead of migrants originating from abroad. MATERIALS AND METHODS: We analyzed the oxygen (18 O/16 O) and strontium (87 Sr/86 Sr) isotope composition of 43 teeth...
April 18, 2018: American Journal of Physical Anthropology
Andrea González-Fernández, Javier Manjarrez, Uri García-Vázquez, Maristella D'Addario, Armando Sunny
Land use and climate change are affecting the abundance and distribution of species. The Trans-Mexican Volcanic Belt (TMVB) is a very diverse region due to geological history, geographic position, and climate. It is also one of the most disturbed regions in Mexico. Reptiles are particularly sensitive to environmental changes due to their low dispersal capacity and thermal ecology. In this study, we define the important environmental variables (considering climate, topography, and land use) and potential distribution (present and future) of the five Thamnophis species present in TMVB...
2018: PeerJ
S M Rodrigues, N Cruz, L Carvalho, A C Duarte, E Pereira, A G F Boim, L R F Alleoni, P F A M Römkens
Intake of soil by children and adults is a major exposure pathway to contaminants including potentially toxic elements (PTEs). However, only the fraction of PTEs released in stomach and intestine are considered as bioaccessible and results from routine analyses of the total PTE content in soils, therefore, are not necessarily related to the degree of bioaccessibility. Experimental methods to determine bioaccessibility usually are time-consuming and relatively complicated in terms of analytical procedures which limits application in first tier assessments...
April 13, 2018: Science of the Total Environment
Heikki Mykrä, Romain Sarremejane, Tiina Laamanen, Satu Maaria Karjalainen, Annamari Markkola, Sirkku Lehtinen, Kaisa Lehosmaa, Timo Muotka
We examined how short-term (19 days) nutrient enrichment influences stream fungal and diatom communities, and rates of leaf decomposition and algal biomass accrual. We conducted a field experiment using slow-releasing nutrient pellets to increase nitrate (NO3 -N) and phosphate (PO4 -P) concentrations in a riffle section of six naturally acidic (naturally low pH due to catchment geology) and six circumneutral streams. Nutrient enrichment increased microbial decomposition rate on average by 14%, but the effect was significant only in naturally acidic streams...
April 16, 2018: Ambio
Peter Vdacný
Trichostome ciliates are among the most conspicuous protists in the gastrointestinal tract of a large variety of vertebrates. However, little is still known about phylogeny of the trichostome/vertebrate symbiotic systems, evolutionary correlations between trichostome extrinsic traits, and character-dependent diversification of trichostomes. These issues were investigated here, using the relaxed molecular clock technique along with stochastic mapping of character evolution, and binary-state speciation and extinction models...
April 11, 2018: Molecular Biology and Evolution
Loïc Chalmandrier, Camille Albouy, Patrice Descombes, Brody Sandel, Soren Faurby, Jens-Christian Svenning, Niklaus E Zimmermann, Loïc Pellissier
Reconstructing the processes that have shaped the emergence of biodiversity gradients is critical to understand the dynamics of diversification of life on Earth. Islands have traditionally been used as model systems to unravel the processes shaping biological diversity. MacArthur and Wilson's island biogeographic model predicts diversity to be based on dynamic interactions between colonization and extinction rates, while treating islands themselves as geologically static entities. The current spatial configuration of islands should influence meta-population dynamics, but long-term geological changes within archipelagos are also expected to have shaped island biodiversity, in part by driving diversification...
March 2018: Royal Society Open Science
Jamal Asfahani
Multifractal Concentration-Number (C-N) modeling approach has been developed and applied to Airborne Gamma Spectrometry (AGS) data related to Area-3, Northern Palmyrides, Syria. The application of the multifractal approach basically aimed at separating uranium anomalies from background. The AGS technique has been applied for uranium exploration in Syria, where four radioactive parameters were recorded, T.C, eU, eTh, and K%. Log-log plots practiced on those radioactive variables indicate the presence of different uranium anomaly ranges...
March 19, 2018: Applied Radiation and Isotopes
Ines Tescione, Sara Marchionni, Martina Casalini, Nadia Vignozzi, Massimo Mattei, Sandro Conticelli
87 Sr/86 Sr was determined on fresh red and white grapes, soils and rocks from three selected vineyards to verify the isotopic relationships between the fruit of the vine and geologic substrata of vineyards. 87 Sr/86 Sr were determined on sampled grapes of four different harvest years and different grape varieties, on bioavailable fraction of soils, on whole soils, and on bedrocks from the geo-pedological substratum of the vineyards. The vineyards chosen for the experimental works belong to an organic farming winery and thus cultivation procedures were strictly controlled...
August 30, 2018: Food Chemistry
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