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Full-Text Articles in Physical Sciences and Mathematics

Morphology Of The Lower Missouri River: The Processes Involving Development Of Highly Sinuous Gooseneck Loop Cutoffs Exposed In The Surficial Deposits Of The River Floodplain, Daniel Earl Carlin Jan 2011

Morphology Of The Lower Missouri River: The Processes Involving Development Of Highly Sinuous Gooseneck Loop Cutoffs Exposed In The Surficial Deposits Of The River Floodplain, Daniel Earl Carlin

Earth & Environmental Sciences Theses - Archive

Mapping the surficial deposits of the Missouri River from Sioux City, Iowa to Mondamin, Iowa brought to light a prominent set of landforms exposed in the floodplain and which are also easily visible via aerial photography. The landforms are segments of highly sinuous channel fills that exhibit the characteristic of turning up-dip against the natural southern gradient of the river valley. These prominent channel scars, of which there are only five exposed in the study area, take on a recognizable “gooseneck” shape. The allostratigraphy for the reach of the Missouri River floodplain from Sioux City to Mondamin was mapped during …

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Reducing Lead Bioavalability In Soil By Adding Apatite Ii, Dhary Saad Alkandary Jan 2011

Reducing Lead Bioavalability In Soil By Adding Apatite Ii, Dhary Saad Alkandary

Earth & Environmental Sciences Theses - Archive

This study was an examination of phosphate-induced immobilization of lead (Pb) in soils through addition of apatite II (fish bone material). The sources of Pb minerals in the soils examined in this in situ remediation study included anglesite (PbSO4), litharge (PbO), and cerrusite (PbCO3). Phosphate-induced Pb immobilization occurs when Pb ions are exchanged with calcium ions to form insoluble lead-phosphate (pyromorphite (Pb5(PO4)3Cl). Commercially available A- horizon soil was spiked with ten different Pb paints that contained different forms of Pb (e.g. PbO, PbCO3, PbSO4) and then sieved through a <250 micron mesh. Two and three replicates were prepared for each Pb paint sample type for apatite and no apatite additions, respectively. A series of large syringe tubes were filled separately with each of the spiked test soils to create a series of soil columns. In all, a set to sixty seven soil columns amended nominally with 5% w/w of apatite, and 2% Pb paint were tested. The change in potential bioavailability of lead in each soil column was evaluated after each column was eluted with Milli-Q water for one year. Soil samples were taken from each column at times zero, six, and twelve months. An in vitro bioaccessibility assessment of each soil column sample was accomplished using a simulated gastric fluid (SGF) digestion to determine the amount of Pb that could potentially be released into solution in the acid conditions in the human stomach. The assay involved using a SGF solution of 100 mL of Milli-Q water, 3 grams of glycine, and hydrochloric acid (HCl) in sufficient quantity to adjust the pH to a value 2.5. To this solution was added 0.5 gram or 1 gram of soil collected at each of the selected time points. Each SGF and soil suspension was tumbled for one hour at 37 °C in a modified Toxicity Characteristic Leaching Procedure (TCLP) system. A Scanning Electron Microscopy (SEM) spectrometer with a Back-Scattered Electron (BSE) detector and an Energy Dispersive X-ray Spectrometer (EDS) was used to obtain photomicrographs of soil samples and to determine the chemical nature of constituent Pb-bearing particles at time zero and at twelve months. A hand-held X-ray florescence (XRF) detector was used to determine the total Pb concentrations in soil samples at time zero. The study found that there was a general reduction in the amount of bioaccessible Pb in the soils at twelve months compared to time zero. This was supported by the identification of Pb-phosphate particle phases in the soils samples at twelve months. The effectiveness of using apatite II to remediate Pb-paint contaminated soil, through the immobilization of Pb through the formation of the sparingly soluble Pb-phosphate mineral pyromorphite (Pb5(PO4)3Cl) appears to be justified.

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Chemostratigraphy Of The Eagle Ford Formation, Timothy J. Kearns Jan 2011

Chemostratigraphy Of The Eagle Ford Formation, Timothy J. Kearns

Earth & Environmental Sciences Theses - Archive

The Late Cretaceous Eagle Ford Formation contains the Cenomanian-Turonian Boundary (CTB). It crops out along the Red River and extends southward through the Dallas-Fort Worth Area of Texas, Waco, Austin and west towards Del Rio and Big Bend. The outcrops were not sampled. Sampling was conducted on cores located at the Bureau of Economic Geology (BEG). The cores were collected from Zavala, La Salle, Frio, Gonzalez, De Witt, and Bee Counties. The Austin Chalk Formation is located above the Eagle Ford Formation and the Buda Formation is located below it. Deposition of the Eagle Ford Formation occurred in the southern …

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Synthesis And Evaluation Of Multicationic Ionic Liquids As Gas Chromatographic Stationary Phases And Synthetic Polymers As Chiral Hplc Stationary Phases, Tharanga Payagala Jan 2011

Synthesis And Evaluation Of Multicationic Ionic Liquids As Gas Chromatographic Stationary Phases And Synthetic Polymers As Chiral Hplc Stationary Phases, Tharanga Payagala

Chemistry & Biochemistry Dissertations - Archive

Due to the characteristics unique to ionic liquids (ILs), they are found in a plethora of applications from simple liquid-liquid extractions to a proposed liquid medium for a lunar telescope. These applications require a thorough knowledge of the physical and chemical properties of ionic liquids and the knowledge to tune the structure to obtain the desired properties. In my dissertation I have described the systematical design and synthesis of a large number of dicationic, trigonal tricationic and linear tricationic ionic liquids. Their physicochemical properties are characterized and the structural variations attributing to the properties such as melting point, thermal stability, …

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An Updated Gps Velocity Field For Puerto Rico And Virgin Islands: Constraints On Tectonic Setting And Internal Deformation, Desmond Kelvin Ihemedu Jan 2011

An Updated Gps Velocity Field For Puerto Rico And Virgin Islands: Constraints On Tectonic Setting And Internal Deformation, Desmond Kelvin Ihemedu

Earth & Environmental Sciences Theses - Archive

Puerto Rico and the northern Virgin Islands define the eastern end of the Greater Antilles, while the Puerto Rico trench and the Muertos Trough define the northern and the southern limits of the North American - Caribbean plate boundary zone. Three microplates have been defined: (1) Gonave, to the west; (2) Hispaniola, at the center; and (3) Puerto Rico and the northern Virgin Islands (PRVI) at the eastern end. Global Positioning System (GPS) geodesy was previously conducted in this region from 1994 to 2003. It was concluded that the locus of the highest permissible on-surface deformation in Puerto Rico and …

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Scalable Parallel Processing Of Multi-Objective Optimized Dna Sequence Assembly, Munib Ahmed Jan 2011

Scalable Parallel Processing Of Multi-Objective Optimized Dna Sequence Assembly, Munib Ahmed

Computer Science and Engineering Dissertations - Archive

Bioinformatics is an emerging branch of science where issues pertaining to molecular biology are evaluated and resolved by leveraging the techniques and algorithms devised in the field of computer science. Most of these issues are due to the enormous amount of data and the computational complexity involved in generating expeditious and qualitatively viable solutions. This poses a challenge to the algorithm developers who must strive to achieve multiple conflicting objectives of processing very large dataset with the highest accuracy possible while keeping the execution time to a minimum. Genome assembly is one such problem in bioinformatics where a DNA sequence …

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Accurate And Cost Efficient Object Localization Using Passive Uhf Rfid, Jae Sung Choi Jan 2011

Accurate And Cost Efficient Object Localization Using Passive Uhf Rfid, Jae Sung Choi

Computer Science and Engineering Dissertations - Archive

In a smart environment, accurate locations of objects are a fundamental and critical issue. To achieve this goal, we present several methods based on passive far-field UHF RFID technologies, which can satisfy accuracy, robustness and reliability, cost efficiency, simplicity, compatibility, and scalability. Our research overcomes several negative characteristics of the use of cost efficient passive UHF RFID. Our research has several important contributions.First, we study the causes of the problems of using passive UHF RFID in localization, with detailed empirical results, and then, present the impacts of the causes on existing localization techniques such as KNN. Second, we present a …

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New Gc Separation Approaches And Analysis Of Antioxidants From Rosemary (Rosmarinus Officinalis L.) And Their Stabilities By Hplc, Ying Zhang Jan 2011

New Gc Separation Approaches And Analysis Of Antioxidants From Rosemary (Rosmarinus Officinalis L.) And Their Stabilities By Hplc, Ying Zhang

Chemistry & Biochemistry Dissertations - Archive

Enantiomeric separations are of great interest in the pharmaceutical, biotechnology and agrochemical industries due to the different therapeutic effects of enantiomers. Because of the high efficiency, sensitivity and simplicity, chiral gas chromatography has been widely applied to separate enantiomers that are volatile and thermally stable. In this dissertation, a group of novel chiral selectors based on cyclofructans for gas chromatography is developed and their enantioselective properties are evaluated.Room temperature ionic liquids (ILs) have been used as gas chromatographic stationary phase due to their unique physical properties in achiral separations. A series of trigonal tricationic ILs are synthesized, characterized and used …

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Capillary Scale Reagent Introduction And Optical Detectors For Capillary Scale Analysis, Santosh K. Mishra Jan 2011

Capillary Scale Reagent Introduction And Optical Detectors For Capillary Scale Analysis, Santosh K. Mishra

Chemistry & Biochemistry Dissertations - Archive

Atmospheric aerosols are of great interest as they have the potential to perturb the earth's radiative energy balance, influence the climate, reduce visibility, and adversely affect human health. The composition of atmospheric particulate matter, especially the concentrations of metals and their ratios, provide insights into sources of the aerosol. Capillary scale ion chromatography systems have several advantages over conventional chromatographic analysis systems like low reagent consumption, small sample requirement, higher efficiencies and better absolute mass detection limits. Hence, to achieve source identification and source apportionment, optical detector based capillary ion chromatography systems are proposed to perform qualitative and quantitative analysis …

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Total Synthesis Of Marine Derived Natural Products: Kealiiquinone And Ageliferin, Heather Marie Lima Jan 2011

Total Synthesis Of Marine Derived Natural Products: Kealiiquinone And Ageliferin, Heather Marie Lima

Chemistry & Biochemistry Dissertations - Archive

An intramolecular Diels-Alder reaction of vinylimidazoles has been developed and applied towards the total synthesis of benzimidazole and tetrahydrobenzimidazole natural products, namely kealiiquinone and ageliferin. A common feature of many imidazole-containing natural products including those of interest in this dissertation is the presence of a 2-amino or 2-imidazolone substituent. A novel method for achieving C2 substitutions has been developed employing chloro-containing reagents. N-Chlorosuccinimide in conjunction with a base has been used to give 2-imidazolones directly from imidazolium salts. This method was then optimized through the use of sodium hypochlorite. This chemistry provides the desired 2-imidazolones in yields ranging from 46-88% …

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Measurement Of The Spectral Distribution Of The Low Energy Electrons Emitted As A Result Of M₃Vv Auger Transitions In Cu(100), Suman Satyal Jan 2011

Measurement Of The Spectral Distribution Of The Low Energy Electrons Emitted As A Result Of M₃Vv Auger Transitions In Cu(100), Suman Satyal

Physics Theses - Archive

Auger Photoelectron Coincidence Spectroscopy (APECS) was used to investigate the physics of the Low Energy Tail (LET) region of the Auger spectrum of a Cu(100) sample. Two Cylindrical Mirror Analyzers (CMAs) were used to select the energy of electrons emitted from the sample as a result of irradiation by 200eV photons. The APECS technique was used to obtain an Auger spectrum taken in coincidence with electrons in the core photoemission peak. The background due to coincidences between pairs of valence electrons emitted as a result of multi-electron photoemission processes was estimated by taking a series of APECS spectra in coincidence …

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Adaptive High Level Context Reasoning In Pervasive Environments, Bridget B. Beamon Jan 2011

Adaptive High Level Context Reasoning In Pervasive Environments, Bridget B. Beamon

Computer Science and Engineering Dissertations - Archive

It is hard to believe that the Internet is now in its adolescent stage. This information age is replete with communication capable, intelligent, sensor equipped devices. Social networks, web services, and global information repositories make a wealth of information available instantly. There exist endless possibilities for creating useable knowledge. Much of what is considered useable knowledge is not directly observable from low level sensory devices. Abstract situations, relationships and activities must be inferred using a variety of techniques that fuse information from multivariate data sources. We refer to this useable knowledge as high level context. Social, physiological, environmental, computational, activity, …

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Correlation Of Sequence Stratigraphic Surfaces Of The Mid-Cretaceous Dakota Group From Subsurface To Outcrop Southern Denver Basin, Colorado., Yaqoub Y Y S M Alsayed Alrefaei Jan 2011

Correlation Of Sequence Stratigraphic Surfaces Of The Mid-Cretaceous Dakota Group From Subsurface To Outcrop Southern Denver Basin, Colorado., Yaqoub Y Y S M Alsayed Alrefaei

Earth & Environmental Sciences Theses - Archive

The D and J sandstone of the Cretaceous Dakota Group are considered as the major oil and gas producing units within in the Denver Basin. The distribution of these units in the Denver Basin is a sub-basin of the Early Cretaceous Western Interior Basin .These units are well understood within the northern Denver Basin and the linkage between the subsurface units and their equivalents in outcrop in the Front Range is well-established. They have gained less attention in southern parts of the basin and the linkage between the subsurface units and their equivalents in southern outcrop is not yet established. …

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Chemostratigraphy And Paleoceanography Of The Mississippian Barnett Formation, Southern Fort Worth Basin, Texas, Usa, James Daniel Hoelke Jan 2011

Chemostratigraphy And Paleoceanography Of The Mississippian Barnett Formation, Southern Fort Worth Basin, Texas, Usa, James Daniel Hoelke

Earth & Environmental Sciences Theses - Archive

The Mississippian (Visean-Serpukhovian) Barnett Formation is a lithologic unit composed primarily of laminated siliceous mudstone and calcareous siliceous mudstone with significant phosphate and sulfide phases present. The Barnett Formation was deposited in the Fort Worth Basin, a marine foreland basin that formed as a result of the early Ouachita Orogeny from the collision of Laurasia and Gondwana. In this study we used a variety of geochemical methods to provide a detailed assessment of the chemostratigraphy and paleoceanography of the Barnett Formation in the southern end of the Fort Worth Basin in Texas. Various aspects of the Barnett Formation studied include: …

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Thermal Maturity And Porosity Development During Catagensis In The Barnett Shale, Fort Worth Basin, Texas, Nathan Glondys Jan 2011

Thermal Maturity And Porosity Development During Catagensis In The Barnett Shale, Fort Worth Basin, Texas, Nathan Glondys

Earth & Environmental Sciences Theses - Archive

Unconventional resource plays are typified by significantly recoverable volumes of thermally mature hydrocarbons (oil, condensate and/or gases) trapped within a low permeability shale formation acting as source, reservoir and seal. These systems pose a scientific and engineering challenge to produce recoverable hydrocarbons from, chiefly due to their low permeabilities. There is growing evidence that secondary porosity in organic gas bearing shales is created during the thermal maturation of kerogen. A better understanding of porosity development during maturation of mobile organics during catagenesis may yield new insight on how we view these systems. A comparative analysis of the gas phase(s), peak …

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Study Of The Response Of The Atlas Tile Calorimeter To Muons Produced In Sqrt(S) = 7 Tev Proton-Proton Collisions At The Lhc, Pierce Ben Weatherly Jan 2011

Study Of The Response Of The Atlas Tile Calorimeter To Muons Produced In Sqrt(S) = 7 Tev Proton-Proton Collisions At The Lhc, Pierce Ben Weatherly

Physics Theses - Archive

The purpose of this study is to verify the inter-calibration of the cells and uniformity of the Tile Calorimeter (TileCal) detector in the ATLAS experiment at CERN. The response using muons produced in proton-proton collisions at sqrt(s)= 7 TeV is identified. Muons are efficient calibration tools because they are minimum ionizing particles that deposit nearly constant energy in the calorimeter for a wide range of particle energies. In this study, the tracks of the muons are extrapolated through the calorimeter, and their path lengths through TileCal cells are calculated. The energy, path length, and dE/dx response of the cells are …

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Investigations In The Impact Of Visual Cognition And Spatial Ability Of Student Comprehension Of Physics And Space Science, Ximena Clara Cuicatl Cid Jan 2011

Investigations In The Impact Of Visual Cognition And Spatial Ability Of Student Comprehension Of Physics And Space Science, Ximena Clara Cuicatl Cid

Physics Dissertations - Archive

Physics and Space Science examine topics that are highly spatial in nature. Students are required to visualize a system, manipulate that system, and then solve a given problem. Doing all of this, simultaneously, can lead to a cognitive overload where the student is unable to correctly solve the problem. Some difficulties may be rooted in conceptual difficulties, whereas other difficulties may arise from issues with spatial intelligence and visual cognition. In some cases, students might have created an incorrect mental image of the problem to begin with, and it's this misconception, not the lack of content knowledge, that has caused …

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Study Of Jet And Missing Transverse Energy Performance In Dijet Events With Atlas Data, Sushmita Sahu Jan 2011

Study Of Jet And Missing Transverse Energy Performance In Dijet Events With Atlas Data, Sushmita Sahu

Physics Theses - Archive

The Large Hadron Collider(LHC) is the world's largest particle collider at CERN, Geneva, operating at a center of mass energy of 7 TeV . The Toroidal LHC Apparatus (ATLAS)is one of two general purpose detectors at the LHC. It is responsible for measuring particles produced in proton-proton collisions and to search for new particles. The High Energy Physics group at UTA has been involved with designing, construction and commissioning of the ATLAS Tile Calorimeter, one of the sub-detectors of ATLAS. One of the components of Tile Cal, the Intermediate Tile Calorimeter (ITC) was constructed at UTA. UTA has been actively …

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An Investigation Of The Conceptual Understanding Of Continuity And Derivatives In Calculus Of Emerging Scholars Versus Non-Emerging Scholars Program Students, Susan Lai Chan Jan 2011

An Investigation Of The Conceptual Understanding Of Continuity And Derivatives In Calculus Of Emerging Scholars Versus Non-Emerging Scholars Program Students, Susan Lai Chan

Mathematics Theses - Archive

The Emerging Scholars Program (ESP) has been adapted at colleges and universities across the nation in efforts to increase student access to Science, Technology, Engineering and Mathematics (STEM) disciplines. This study uses a written assessment to gain insight regarding conceptual knowledge on continuity and derivatives for ESP students versus non-ESP students in the same lecture course in first semester calculus at large urban university in the southwest. We analyze the assessment results of 22 ESP and 48 non-ESP students and discuss findings, particularly, those that indicate statistically significant differences regarding continuity over an interval.

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A Snapshot Of Advanced High School Students' Understanding Of Continuity, Melissa Jo Vela Jan 2011

A Snapshot Of Advanced High School Students' Understanding Of Continuity, Melissa Jo Vela

Mathematics Theses - Archive

We report on a study of sixteen high school calculus and seven precalculus students' concept image and concept definition of continuity after one-trimester of instruction at a large suburban high school in the southwestern United States. The researchers developed a questionnaire based upon the work of Tall and Vinner (1981) to determine if calculus students had developed a more sophisticated concept image and concept definition of continuity than students in pre-calculus after a typical treatment in both courses. Using data from the written assessment it was not evident that calculus students demonstrated a more sophisticated concept image and concept definition …

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Calibration Of The Atlas Intermediate Tile Calorimeter, Heather Brianna Brown Jan 2011

Calibration Of The Atlas Intermediate Tile Calorimeter, Heather Brianna Brown

Physics Theses - Archive

The Large Hadron Collider (LHC) at CERN near Geneva, Switzerland is the world's largest particle collider. UTA contributes to the ATLAS detector at the LHC. There are many detection systems within ATLAS, and the hadronic calorimeter (TileCal) is the main interest of the HEP group at UTA. A piece of the TileCal was constructed at UTA and is called the Intermediate Tile Calorimeter (ITC).The ITC is installed in a service region of the detector and the ITC behave differently from other TileCal cells. Due to a different geometry, the ITC cells require special attention and a different method of calibration. …

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On The Electronic And Geometric Structure Properties Of Silicon-Germanium Nanoclusters: A Hybrid Density Functional Theoretic Study, Sarah Elizabeth Duesman Jan 2011

On The Electronic And Geometric Structure Properties Of Silicon-Germanium Nanoclusters: A Hybrid Density Functional Theoretic Study, Sarah Elizabeth Duesman

Physics Theses - Archive

Hybrid density functional theory has been used to study the electronic and geometric structure properties of silicon-germanium nanoclusters containing up to eight atoms. The hybrid functional used is Becke's three-parameter exchange functional with the exchange-correlation functional of Lee, Yang, and Parr (B3LYP). A large 6-311G(3df,3pd) basis set as implemented in the suite of software Gaussian 03/09 has been used for accurate determinations of all properties of the SimGen (m + n [lesser or equal to] 8) nanoclusters. For each cluster, various different isomers have been studied to arrive at a global minimum energy structure, and for each of these isomers …

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Synthesis And Characterization Of Lanthanide Based Nanomaterials For Radiation Detection And Biomedical Applications, Mingzhen Yao Jan 2011

Synthesis And Characterization Of Lanthanide Based Nanomaterials For Radiation Detection And Biomedical Applications, Mingzhen Yao

Physics Dissertations - Archive

Lanthanide based nanomaterials have shown a great potential in various areas such as luminescence imaging, luminescent labels, and detection of cellular functions. Due to the f-f transitions of the metal ion, luminescence of lanthanide ions is characterized by sharp and narrow emissions. In this dissertation lanthanide based nanoparticles such as Ce3+, Eu3+ and other lanthanide ions doped LaF3 were synthesized, their characterization, encapsulation and embedding into hybrid matrix were investigated and some of their biomedical and radiological applications were studied.DMSO is a common solvent which has been used widely for biological applications.LaF3:Ce nanoparticles were synthesized in DMSO and it was …

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Measurement Of Single Diffractive Differential Cross Section (Dσ/(D|T|)) At √(S ) = 1.96 Tev Using The D0 Forward Proton Detectors, Arnab Kumar Pal Jan 2011

Measurement Of Single Diffractive Differential Cross Section (Dσ/(D|T|)) At √(S ) = 1.96 Tev Using The D0 Forward Proton Detectors, Arnab Kumar Pal

Physics Dissertations - Archive

The analysis described in this dissertation uses the Forward Proton Detectors (FPD) installed at the D0 detector in the Tevatron collider at Fermilab to measure the single diffractive differential cross section (d&sigma/(d|t|)) at sqrt(s ) = 1.96 TeV center of mass energy. The single diffractive events are selected using the D0 central detector and the FPD system and |t| of the forward proton are measured using the FPD system. The analysis presents the measurement of the differential cross section of the single diffractive events as a function of |t| in the range 0.2 < |t| < 1.3 GeV2. The differential cross section measurement is within the theoretical and experimental expectations. The total single diffractive cross section (&sigma_sd ) in the region 0.0 < |t| < 1.3 GeV2 is found to be 9.682 ± 0.048(stat.) ± 1.219(syst.) mb.

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Flexible Use Of Anti-Predator Defences, Ximena J. Nelson, Robert R. Jackson Jan 2011

Flexible Use Of Anti-Predator Defences, Ximena J. Nelson, Robert R. Jackson

All Peer-Reviewed Publications

Belonging to a size category that makes them vulnerable to a wide variety of predators, spiders have evolved a bewildering array of anti-predator adaptations, which can be clustered under two broad categories, primary and secondary defence. Primary defences are ploys by which the spider avoids provoking pursuit by, and interaction with, the predator. Camouflage and masquerade are especially common examples. Secondary defences come into play once an interaction with a predator is under way, and these are the defences that have been most thoroughly studied. However, elements of anti-predator defence may often be integrated into other aspects of the spider's …

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Will The Convention On Biological Diversity Put An End To Biological Control?, Joop C. Van Lenteren, Matthew J.W. Cock, Jacques Brodeur, Barbara I.P. Barratt, Franz Bigler, Karel Bolckmans, Fabian Haas, Peter G. Mason, José Roberto P. Parra Jan 2011

Will The Convention On Biological Diversity Put An End To Biological Control?, Joop C. Van Lenteren, Matthew J.W. Cock, Jacques Brodeur, Barbara I.P. Barratt, Franz Bigler, Karel Bolckmans, Fabian Haas, Peter G. Mason, José Roberto P. Parra

All Peer-Reviewed Publications

Will the Convention on Biological Diversity put an end to biological control? Under the Convention on Biological Diversity countries have sovereign rights over their genetic resources. Agreements governing the access to these resources and the sharing of the benefits arising from their use need to be established between involved parties. This also applies to species collected for potential use in biological control. Recent applications of access and benefit sharing principles have already made it difficult or impossible to collect and export natural enemies for biological control research in several countries. If such an approach is widely applied it would impede …

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Efficiency Of Phytoseiulus Longipes Evans As A Control Agent Of Tetranychus Evansi Baker & Pritchard (Acari: Phytoseiidae: Tetranychidae) On Screenhouse Tomatoes, Fernando R. Da Silva, Gilberto J. De Moraes, Manoel G.C. Gondim, Markus Knapp, Sigrid L. Rouam, Jefferson L.A. Paes, Guilherme M. De Oliveira Nov 2010

Efficiency Of Phytoseiulus Longipes Evans As A Control Agent Of Tetranychus Evansi Baker & Pritchard (Acari: Phytoseiidae: Tetranychidae) On Screenhouse Tomatoes, Fernando R. Da Silva, Gilberto J. De Moraes, Manoel G.C. Gondim, Markus Knapp, Sigrid L. Rouam, Jefferson L.A. Paes, Guilherme M. De Oliveira

All Peer-Reviewed Publications

The spider mite Tetranychus evansi Baker & Pritchard can cause severe damage to tomato crops. The predatory mite Phytoseiulus longipes Evans was recently reported in association with T. evansi in Uruguaiana, Rio Grande do Sul State, Brazil. The objective of the present study was to evaluate the effects of P. longipes on the population of T. evansi on tomatoes under screenhouse condition. The study consisted on four experiments, in each of which 80 potted plantlets were distributed in two plots of 40 plantlets each. Two weeks later, each plantlet of both plots was infested with eight adult females of T. …

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Veritas Search For Vhe Gamma-Ray Emission From Dwarf Spheroidal Galaxies, P. T. Reynolds, Et. Al. Sep 2010

Veritas Search For Vhe Gamma-Ray Emission From Dwarf Spheroidal Galaxies, P. T. Reynolds, Et. Al.

Physical Sciences Publications

Indirect dark matter searches with ground-based gamma-ray observatories provide an alternative for identifying the particle nature of dark matter that is complementary to that of direct search or accelerator production experiments. We present the results of observations of the dwarf spheroidal galaxies Draco, Ursa Minor, Boötes 1, and Willman 1 conducted by the Very Energetic Radiation Imaging Telescope Array System (VERITAS). These galaxies are nearby dark matter dominated objects located at a typical distance of several tens of kiloparsecs for which there are good measurements of the dark matter density profile from stellar velocity measurements. Since the conventional astrophysical background …

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New Biologically Active Compounds From Kenyan Propolis, Assya Petrova, Milena Popova, Christina Kuzmanova, Iva Tsvetkova, Hristo Naydenski, Eliud Muli, Vassya Bankova Sep 2010

New Biologically Active Compounds From Kenyan Propolis, Assya Petrova, Milena Popova, Christina Kuzmanova, Iva Tsvetkova, Hristo Naydenski, Eliud Muli, Vassya Bankova

All Peer-Reviewed Publications

From propolis samples from Kenya, two new arylnaphtalene lignans were isolated, tetrahydrojusticidin B 1 and 6-methoxydiphyllin 2, along with four known phenolic compounds 5-8, found for the first time in propolis. The structures of the compounds were elucidated based on their spectral properties. The geranylstilbenes 7 and 8 demonstrated antibacterial activity against S. aureus, and the geranylflavon macarangin 6 possessed antiradical activity against DPPH radicals. © 2010 Elsevier B.V. All rights reserved.

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What Are You Looking For: Identification Of Remnant Communication Artefacts In Physical Memory, Matthew Simon, Jill Slay Aug 2010

What Are You Looking For: Identification Of Remnant Communication Artefacts In Physical Memory, Matthew Simon, Jill Slay

International Cyber Resilience conference

Law enforcement has sound methods for investigating and obtaining data about targets that are using traditional communication services such as the Public Switched Telephone Network. The Internet as a data transfer medium is a vastly different paradigm to that of traditional telephony networks. Information about targets using Internet communication technologies cannot be obtained using the same methods used for traditional communication. There has been an identified need for methods to obtain information on targets that have been using Internet communication methods. The acquisition and analysis of physical memory has been proposed as a vector for the recovery of such information. …

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