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Soil As A History Book, Bradley Allen Miller 2010 Iowa State University

Soil As A History Book, Bradley Allen Miller

Agronomy Publications

Soil is one of the most influential components of our enviroronment. It is a complex mixture of physical, chemical, and biological processes providing innumerable ecosystem services. The properties of our soil today support our way of life. It filters our water, contains our wastes, and is the substrate for the production of our food. Combined with a good climate, the convergence of the right soil properties here in Iowa has given its citizens the opportunity to be net exporters of food and feed. That opportunity gives Iowans the ability to feed themselves and prosper economically through the sale of excess ...


Molecular Structure Of Fac-Aquadichlorotris(Dimethylsulfoxide)Ruthenium(Ii), L. Foster, J. Hardin, Mark Draganjac, B. C. Noll 2010 Arkansas State University

Molecular Structure Of Fac-Aquadichlorotris(Dimethylsulfoxide)Ruthenium(Ii), L. Foster, J. Hardin, Mark Draganjac, B. C. Noll

Journal of the Arkansas Academy of Science

No abstract provided.


Optical Characterization Of Silver Doped Poly (Vinyl Alcohol) Films, W. A. Jabbar, N. F. Habubi, S. S. Chiad 2010 Al Mustasiriyah University

Optical Characterization Of Silver Doped Poly (Vinyl Alcohol) Films, W. A. Jabbar, N. F. Habubi, S. S. Chiad

Journal of the Arkansas Academy of Science

Silver-doped PVA films were prepared by casting method in order to study the effect of silver on the optical properties of poly(vinyl alcohol) using UV/VIS spectroscopy. It was found that these thin films have an indirect optical band gap (2.4-1.3) eV as the doping percentage increase. Extinction coefficient and refractive index increase as the doping percentage increase, while in general the optical dispersion parameters show an opposite behavior with doping


Characterization Of Secondary Organic Aerosol (Soa) Formed By The Reaction Of Β-Caryophyllene, Soot And Ozone: Climate Impact, A. Sarkar, N. A. Marley, J. S. Gaffney 2010 University of Arkansas at Little Rock

Characterization Of Secondary Organic Aerosol (Soa) Formed By The Reaction Of Β-Caryophyllene, Soot And Ozone: Climate Impact, A. Sarkar, N. A. Marley, J. S. Gaffney

Journal of the Arkansas Academy of Science

Diesel soot (black carbon, BC) is an important light absorbing aerosol component in atmosphere that can cause tropospheric heating. Laboratory studies have found it to be unreactive to ozone at ambient temperature. The low uptake coefficient i.e., γ 300 K = 2× 10-7 , of the soot-O3 reaction indicates a low probability of irreversible O3 loss from gas phase to surface-adsorbed product (Particle phase). This shows clearly that at low temperature soot is not reactive with atmospheric oxidants. In contrast, sesquiterpenes (SQT) such as β-caryophyllene (C15H24), which are produced primarily by plants, are extremely reactive with ozone. For example, the residence ...


Millennial-Scale Climate Variability During The Last Glacial Period In The Tropical Andes, Sherilyn C. Fritz, P. A. Baker, E. Ekdahl, G. O. Seltzer, L. R. Stevens 2010 University of Nebraska-Lincoln

Millennial-Scale Climate Variability During The Last Glacial Period In The Tropical Andes, Sherilyn C. Fritz, P. A. Baker, E. Ekdahl, G. O. Seltzer, L. R. Stevens

Papers in the Earth and Atmospheric Sciences

Millennial-scale climate variation during the Last Glacial period is evident in many locations worldwide, but it is unclear if such variation occurred in the interior of tropical South America, and, if so, how the low-latitude variation was related to its high-latitude counterpart. A high-resolution record, derived from the deep drilling of sediments on the floor of Lake Titicaca in the southern tropical Andes, is presented that shows clear evidence of millennial-scale climate variation between ~60 and 20 ka BP. This variation is manifested by alternations of two interbedded sedimentary units. The two units have distinctive sedimentary, geochemical, and paleobiotic properties ...


Climatic And Environmental Controls On The Occurrence And Distributions Of Long Chain Alkenones In Lakes Of The Interior United States, Jaime L. Toney, Yongsong Huang, Sherilyn C. Fritz, Paul A. Baker, Eric Grimm, Paul Nyren 2010 Brown University

Climatic And Environmental Controls On The Occurrence And Distributions Of Long Chain Alkenones In Lakes Of The Interior United States, Jaime L. Toney, Yongsong Huang, Sherilyn C. Fritz, Paul A. Baker, Eric Grimm, Paul Nyren

Papers in the Earth and Atmospheric Sciences

Long chain alkenones (LCA) are temperature-sensitive lipids with great potential for quantitative reconstruction of past continental climate. We conducted the first survey for alkenone biomarkers from 55 different lakes in the Northern Great Plains and Nebraska Sand Hills of the United States. Among those surveyed, we found 13 lakes that contain LCAs in the surface sediments. The highest concentrations of alkenones in sediments are found in cold (mean annual air temperature ~11 °C versus 17 °C in our warmest sites), brackish to mesosaline (salinity = 8.5–9.7 g/L), and alkaline (pH = 8.4–9.0) lakes with high ...


Investigating An Optimal Decision Point For Probability Bounds Analysis Models When Used To Estimate Remedial Soil Volumes Under Uncertainty At Hazardous Waste Sites, Charles O. Dankwah 2010 Walden University

Investigating An Optimal Decision Point For Probability Bounds Analysis Models When Used To Estimate Remedial Soil Volumes Under Uncertainty At Hazardous Waste Sites, Charles O. Dankwah

Walden Dissertations and Doctoral Studies

Hazardous waste site remediation cost estimation requires a good estimate of the contaminated soil volume. The United States Environmental Protection Agency (U.S. EPA) currently uses deterministic point values to estimate soil volumes but the literature suggests that probability bounds analysis (PBA) is the more accurate method to make estimates under uncertainty. The underlying statistical theory is that they are more accurate than deterministic estimates because probabilistic estimates account for data uncertainties. However, the literature does not address the problem of selecting an optimal decision point from the interval-valued PBA estimates. The purpose of this study was to identify the ...


A Correlational Study Of Telework Frequency, Information Communication Technology, And Job Satisfaction Of Home-Based Teleworkers, Shana P. Webster-Trotman 2010 Walden University

A Correlational Study Of Telework Frequency, Information Communication Technology, And Job Satisfaction Of Home-Based Teleworkers, Shana P. Webster-Trotman

Walden Dissertations and Doctoral Studies

In 2008, 33.7 million Americans teleworked from home. The Telework Enhancement Act (S. 707) and the Telework Improvements Act (H.R. 1722) of 2009 were designed to increase the number of teleworkers. The research problem addressed was the lack of understanding of factors that influence home-based teleworkers' job satisfaction. Job dissatisfaction has been found to have a significant impact on voluntary turnover. The purpose of the study was to assess the relationship among telework frequency, information communication technology (ICT), and job satisfaction. The research questions were designed to answer whether correlational relationships exist among telework frequency, ICT, and job ...


The Effect Of Learning Styles Strategies On Benchmark Eighth Grade Middle School Mathematics Achievement, Jean Ferrara 2010 Walden University

The Effect Of Learning Styles Strategies On Benchmark Eighth Grade Middle School Mathematics Achievement, Jean Ferrara

Walden Dissertations and Doctoral Studies

Low standardized mathematics scores resulted in a suburban middle school not reaching adequate yearly progress (AYP) for the 2 previous years. There were many possible factors contributing to this problem, among them the design of instruction. The purpose of this study was to identify learning styles of students and implement differentiated instructional strategies that address the learners' needs. The study was based on the Silver and Hanson's theory of learning style instruction and Gardner's multiple intelligences as a model for differentiating instruction. This sequential mixed methods quasi-experimental causal comparative design study investigated the effect of classroom intervention based ...


Assimilative Domain Proficiency And Performance In Chemistry Coursework, Scott WIlliam Byrnes 2010 Walden University

Assimilative Domain Proficiency And Performance In Chemistry Coursework, Scott William Byrnes

Walden Dissertations and Doctoral Studies

The assimilation and synthesis of knowledge is essential for students to be successful in chemistry, yet not all students synthesize knowledge as intended. The study used the Learning Preference Checklist to classify students into one of three learning modalities -- visual, auditory, or kinesthetic (VAK). It also used the Kolb Learning Style Inventory (KLSI), which utilizes four learning domains - Converging, Accommodating, Diverging, and Assimilating - to explain the students' maturation process by showing shift from any domain towards the Assimilating domain. A shift approaching this domain was considered as improvement in the assimilation and synthesis of knowledge. This pre-experimental one-group pretest-posttest study ...


Ecological And Evolutionary Connectivity Of Reef Corals In Subtropical Eastern Australia: Implications For The Persistence Of High-Latitude Coral Populations, Annika ME Noreen 2010 Southern Cross University

Ecological And Evolutionary Connectivity Of Reef Corals In Subtropical Eastern Australia: Implications For The Persistence Of High-Latitude Coral Populations, Annika Me Noreen

Theses

Coral reefs worldwide are threatened by a variety of pressures, and climate change models predict increasing levels of chronic stress as well as acute disturbances for most reefs. In addition to these global threats, populations on remote reefs are also predicted to be vulnerable due to their isolation from potential source reefs, usually low population size and associated increased extinction risk. Critical for the future of these reefs is dispersal and gene flow between populations (connectivity).

This study investigated connectivity, population subdivision, and genetic diversity for three scleractinian reef coral species in discontinuous high-latitude nearshore coral communities and offshore reefs ...


The Planet, 2010, Winter, Kaylin Bettinger, Huxley College of the Environment, Western Washington University 2010 Western Washington University

The Planet, 2010, Winter, Kaylin Bettinger, Huxley College Of The Environment, Western Washington University

The Planet

Managing Editor: Anne Maertens; Editors: Oliver Lazenby, Olivia Scalet; Science Editor: Stephanie Eckard; Designers: Kim Gladow, Brianna Nieman; Photographers: Mitch Olsen, Jordan Stead, Marybeth Coghill, Colin Diltz, Talithia Taitano; Writers: Mitch Olsen, James Andrews, Chris Collinson, Courtney Leake, Brooke Loisel, Andrea Farrell, Amanda Halle, Zoie Caidos


Status Of Wintering Grassland Birds In A Post-Hurricane, Salvage-Logged Forest, Matthew Edward Brooks 2010 Louisiana State University and Agricultural and Mechanical College

Status Of Wintering Grassland Birds In A Post-Hurricane, Salvage-Logged Forest, Matthew Edward Brooks

LSU Master's Theses

North American grassland birds have been declining at an alarming rate. Winter habitat for grassland species in the southeastern U.S. generally occurs within forests subject to management. I studied wintering grassland bird communities in De Soto National Forest in southern Mississippi. My objectives were to: 1) Assess bird communities and vegetation structure in upland forest stands that were salvage-logged following Hurricane Katrina, in stands managed for Red-cockaded Woodpeckers (Picoides borealis, RCW), and in stands containing bogs; and 2) Determine the extent of the association between vegetation and occurrence of the common wintering grassland birds. I conducted bird and vegetation ...


Effects Of Habitat Structural Complexity On Nekton Assemblages: Lab And Field Observations In Southern Louisiana, Austin T. Humphries 2010 Louisiana State University and Agricultural and Mechanical College

Effects Of Habitat Structural Complexity On Nekton Assemblages: Lab And Field Observations In Southern Louisiana, Austin T. Humphries

LSU Master's Theses

Greater structural complexity is often associated with more diverse and abundant species assemblages. Biogenic reefs formed by the eastern oyster (Crassostrea virginica) are structurally complex in nature and have been recognized for their potential habitat value in estuarine systems along the Atlantic and Gulf of Mexico coasts. To determine how the structural complexity of newly created oyster reefs may influence the abundance and distribution of species, three objectives were established. First, to examine spatial and temporal patterns of nekton use at newly created oyster reefs, as well as the impact of wave exposure, six paired oyster reef and mud-bottom treatments ...


Introgression, Health, And Condition Of Florida, Northern, And Fx Hybrid Largemouth Bass In Louisiana Water Bodies, Melissa Ann Fries 2010 Louisiana State University and Agricultural and Mechanical College

Introgression, Health, And Condition Of Florida, Northern, And Fx Hybrid Largemouth Bass In Louisiana Water Bodies, Melissa Ann Fries

LSU Master's Theses

Since 1982, the Louisiana Department of Wildlife and Fisheries (LDWF) has stocked Florida-strain largemouth bass (FLMB; Micropterus salmoides floridanus) to incorporate Florida alleles into native populations (NLMB; M. s. salmoides) and enhance recreational fishing opportunities. I collected habitat data and largemouth bass samples from 12 LDWF stocked reservoirs and disconnected oxbow lakes to examine the relationships between reservoir characteristics, genetic identity, relative weight (Wr), liver somatic index (LSI), parasite loads, and back-calculated length-at-age. I examined the relationships between water body and genetic identity with Wr, LSI, and back-calculated length-at-age by ANOVA. Parasite loads were analyzed with ordinal regression. Principle component ...


The Effects Of Self-Assessment On Student Learning Of Mathematics, Daniel James Hotard 2010 Louisiana State University and Agricultural and Mechanical College

The Effects Of Self-Assessment On Student Learning Of Mathematics, Daniel James Hotard

LSU Master's Theses

Self-assessment can be defined as students judging their own work, based on evidence and explicit criteria, for the purpose of improving future performance. Many researchers agree that implementation of student self-assessment in the classroom is an important tool for improving academic performance and self-efficacy. In this thesis, I investigated the effects of student self-assessment on learning gains of 81 alternative high school Algebra I students. This study took place over the course of two units of instruction. Classes were divided into two groups. One group of students utilized rubrics to self-assess their own work for the first unit, while the ...


The Science, The Technology, The Law, Ken Fowle 2010 Department of Mines and PetroleumPerth, Western Australia

The Science, The Technology, The Law, Ken Fowle

Australian Digital Forensics Conference

Forensic science must satisfy two needs; that of the scientific community and that of the legal profession. It is hoped that the legal and scientific outcomes should be based on one and the same thing. Science, Technology and Law depend upon the establishment of a reliable basis of fact. But in the Court it is the law that finally decides what is fact, what is opinion and what the truth should be. This paper looks at the role of the Forensic Practitioner’s requirement for understanding the science, the technology and the law. It endeavours to explain the reasons, using ...


Fireguard - A Secure Browser With Reduced Forensic Footprint, Don Griffiths, Peter James 2010 Curtin University of Technology

Fireguard - A Secure Browser With Reduced Forensic Footprint, Don Griffiths, Peter James

Australian Digital Forensics Conference

Fireguard is a secure portable browser designed to reduce both data leakage from browser data remnants and cyber attacks from malicious code exploiting vulnerabilites in browser plug-ins, extensions and software updates. A browser can leave data remnants on a host PC hard disk drive, often unbeknown to a user, in the form of cookies, histories, saved passwords, cached web pages and downloaded objects. Forensic analysis, using freely available computer forensic tools, may reveal sensitive and confidential information. A browser’s capability to increase its features through plug-ins and extensions and perform patch management or upgrade to a new release via ...


Does The Use Of Mimo Technology Used By 802.11n Reduce Or Increase The Impact Of Denial Of Service Attacks?, William Pung, Andrew Woodward 2010 Edith Cowan University

Does The Use Of Mimo Technology Used By 802.11n Reduce Or Increase The Impact Of Denial Of Service Attacks?, William Pung, Andrew Woodward

Australian Digital Forensics Conference

This paper presents the results of a simulated wireless DoS attack against a 802.11g connection that uses Single Input Single Output (SISO), and an 802.11n device that utilizes MIMO. The aim of the experiment was to determine whether the impact of a denial of service attack against MIMO architecture is greater than SISO, since it is capable of receiving more(multiple) attack frames/packets within a given time frame. It was found that both devices were negatively impacted by such attacks, and that throughout was similarly affected. It was also observed that increasing the packet flood rate resulted ...


Zombie Hard Disks - Data From The Living Dead, Iain Sutherland, Gareth Davies, Andy Jones, Andrew J. C. Blyth 2010 University of Glamorgan

Zombie Hard Disks - Data From The Living Dead, Iain Sutherland, Gareth Davies, Andy Jones, Andrew J. C. Blyth

Australian Digital Forensics Conference

There have been a number of studies conducted in relation to data remaining on disks purchased on the second hand market. A large number of these studies have indicated that a proportion of these disks contain a degree of residual data placed on the drive by the original owners. The Security Research Centre at BT has sponsored a residual data study over the last five years examining disks sourced around the globe, in the UK, USA, Germany France and Australia. In 2008 as part of a 5 year study, Glamorgan University in conjunction with Edith Cowan University in Australia, Longwood ...


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