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2010

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Articles 421 - 450 of 8621

Full-Text Articles in Physical Sciences and Mathematics

Apertureless Near-Field/Far-Field Cw Two-Photon Microscope For Biological And Material Imaging And Spectroscopic Applications, Derek Brant Nowak, Andrew James Lawrence, Erik J. Sánchez Dec 2010

Apertureless Near-Field/Far-Field Cw Two-Photon Microscope For Biological And Material Imaging And Spectroscopic Applications, Derek Brant Nowak, Andrew James Lawrence, Erik J. Sánchez

Physics Faculty Publications and Presentations

We present the development of a versatile spectroscopic imaging tool to allow for imaging with single-molecule sensitivity and high spatial resolution. The microscope allows for near-field and subdiffraction-limited far-field imaging by integrating a shear-force microscope on top of a custom inverted microscope design. The instrument has the ability to image in ambient conditions with optical resolutions on the order of tens of nanometers in the near field. A single low-cost computer controls the microscope with a field programmable gate array data acquisition card. High spatial resolution imaging is achieved with an inexpensive CW multiphoton excitation source, using an apertureless probe …


The Role Of Sulfur In Biomineralization: Argopecten Irradians And The Impact Of Ocean Acidification, Bryanna Joy Broadaway Dec 2010

The Role Of Sulfur In Biomineralization: Argopecten Irradians And The Impact Of Ocean Acidification, Bryanna Joy Broadaway

Graduate Masters Theses

The burning of fossil fuels, and other natural processes, has led to an increase of carbon dioxide (CO2) in the atmosphere. The equilibration of atmospheric CO2 with surface waters causes the ocean pH to decrease from the current value of 8.1. Evidence suggests that as the ocean becomes more alkaline, organisms such as the bay scallop, Argopecten irradians¸will become more stressed due to increased energy demands to maintain shell deposition and growth. This stress, as hypothesized here, may cause the deposition of S-bearing organic macromolecules to aid in mineralization as well as the potential for sulfate …


How Are The Torres Strait Islander's Traditional Hunting Practices Affected By The Current Rate Of Decline In Dugong And Sea Turtle Populations And The Australian Government's Co-Management Policies On Marine Preservation?, Katilyn Price Dec 2010

How Are The Torres Strait Islander's Traditional Hunting Practices Affected By The Current Rate Of Decline In Dugong And Sea Turtle Populations And The Australian Government's Co-Management Policies On Marine Preservation?, Katilyn Price

Department of Environmental Studies: Undergraduate Student Theses

This paper will attempt to identify the extent to which the Torres Strait Islanders traditional hunting practices have been disrupted by the overall decline in dugong and sea turtle populations, which has directly correlated to an increase in hunting restrictions put in place by the Australian Government. The traditional hunting of dugongs and sea turtles provides not only a food source, but brings prestige to the men who catch them and serves as an educational platform to teach the younger generations about their culture. There are many environmental threats that impact the populations of sea turtles and dugongs though the …


The Influence Of Sediment Bays On Reducing Incoming Sediment In Holmes Lake: Lincoln, Nebraska, Alex Fischer Dec 2010

The Influence Of Sediment Bays On Reducing Incoming Sediment In Holmes Lake: Lincoln, Nebraska, Alex Fischer

Department of Environmental Studies: Undergraduate Student Theses

Lakes in the urban environment are often challenged with issues of water quality. Holmes Lake, located in Lincoln, Nebraska, has experienced such problems. In an effort to improve water quality in Holmes Lake, the city installed several control devices. One of the devices installed were sediment bays. This study evaluated the effectiveness of those sediment bays by measuring turbidity and suspended sediment after rain events at different locations in and out of the bays. The study found that the bays helped to reduce sediment in some cases, but in other cases no reduction was shown.


Educators' Attitudes Toward Outdoor Classrooms And The Cognitive Benefits In Children, Carlie Speedlin Dec 2010

Educators' Attitudes Toward Outdoor Classrooms And The Cognitive Benefits In Children, Carlie Speedlin

Department of Environmental Studies: Undergraduate Student Theses

A case study was organized at a K-5 elementary school in Lincoln, Nebraksa. This school is Saratoga Elementary School and is a United States Title I Distinguished School1 under No Child Left Behind. It has a population of 266 students, with 47% being minority, 1% gifted, and 28% special education (LPS School Profile Brochure). 80% of the student population is eligible for free/reduced meals, implying that it’s a school with a lower socioeconomic status. At this school a garden space was constructed and an after school garden club was implemented for this case study. The club had been running since …


Recent Legislation To Promote Wind Energy In Nebraska, Ryan Lemke Dec 2010

Recent Legislation To Promote Wind Energy In Nebraska, Ryan Lemke

Department of Environmental Studies: Undergraduate Student Theses

Nebraska is currently ranked 4th in the nation for wind energy potential, but ranks low in actual wind power production. The lack of wind energy production could be the result of Nebraska’s unique public power districts that have eminent domain of distribution and retail sales of electricity in the State. Public Power districts are prohibited from receiving benefits of state and federal tax incentives for the development of wind farms, however some Nebraska power districts still pursue wind energy as a renewable source of energy.

Recent legislation changes, including the passing of laws LB629 and LB1048, have provided the State …


Is Orthoptera Abundance And Distribution Across A Small Grassland Area Affected By Plant Biomass, Plant Species Richness, And Plant Quality?, Caitlin Falcone Dec 2010

Is Orthoptera Abundance And Distribution Across A Small Grassland Area Affected By Plant Biomass, Plant Species Richness, And Plant Quality?, Caitlin Falcone

Department of Environmental Studies: Undergraduate Student Theses

The choice of a specific microhabitat represents a compromise among a number of different factors organisms use to monitor habitat suitability. Grassland vegetation structure can vary widely along environmental gradients over a relatively small area. This vegetation structure can have a large influence on habitat selection by grasshoppers (Orthoptera). However, it is not clear which vegetation characteristics are most important in determining grasshopper abundance. We found that plant biomass, plant species richness, and plant quality all have an effect on grasshopper abundance and distribution. We observe that these affects vary both within and among the two years of data collection. …


Efficacy Of The United States Safe Harbor Framework, Margaret M. Beck Dec 2010

Efficacy Of The United States Safe Harbor Framework, Margaret M. Beck

Regis University Student Publications (comprehensive collection)

This study assessed the efficacy of the United States Safe Harbor Framework by approximating the size of a population of large United States organizations (50,000 - 500,000 employees) that were eligible to participate in the Safe Harbor that did not participate. The Safe Harbor Framework, administered by the United States Department of Commerce, is a voluntary program that assists United States organizations in complying with the European Union Data Privacy Directive. Out of a population of 337 large organizations, 168 were potentially eligible to participate in the Safe Harbor Framework. One hundred and ten, or 66%, of these organizations did …


Two-Layered Pulsatile Blood Flow In A Stenosed Artery With Body Acceleration And Slip At Wall, Devajyoti Biswas, Uday Shankar Chakraborty Dec 2010

Two-Layered Pulsatile Blood Flow In A Stenosed Artery With Body Acceleration And Slip At Wall, Devajyoti Biswas, Uday Shankar Chakraborty

Applications and Applied Mathematics: An International Journal (AAM)

Pulsatile flow of blood through an artery in presence of a mild stenosis has been investigated in this paper assuming the body fluid blood as a two-fluid model with the suspension of all the erythrocytes in the core region as Bingham Plastic and the peripheral region of plasma as a Newtonian fluid. This model has been used to study the influence of body acceleration, non- Newtonian nature of blood and a velocity slip at wall, in blood flow through stenosed arteries. By employing a perturbation analysis, analytic expressions for the velocity profile, Plug-core radius, flow rate, wall shear stress and …


Application Of Homotopy Perturbation Method To Biological Population Model, Pradip Roul Dec 2010

Application Of Homotopy Perturbation Method To Biological Population Model, Pradip Roul

Applications and Applied Mathematics: An International Journal (AAM)

In this article, a well-known analytical approximation method, so-called the Homotopy perturbation method (HPM) is adopted for solving the nonlinear partial differential equations arising in the spatial diffusion of biological populations. The resulting solutions are compared with those of the existing solutions obtained by employing the Adomian’s decomposition method. The comparison reveals that our approximate solutions are in very good agreement with the solutions by Adomian’s method. Moreover, the results show that the proposed method is a more reliable, efficient and convenient one for solving the non-linear differential equations.


Reliability Measures Of A Three-State Complex System: A Copula Approach, Mangey Ram Dec 2010

Reliability Measures Of A Three-State Complex System: A Copula Approach, Mangey Ram

Applications and Applied Mathematics: An International Journal (AAM)

Improvement in reliability and production play a very important role in system design. The two key factors, considered in predicting system reliability, are failure distribution of the component and system configuration. This research discusses the mathematical modeling of a highly reliable complex system, which is in three states i.e. normal, partial failed (degraded state) and complete failed state. The system, partial failed is due to the partial failure of internal components or redundancies and completely failed is due to catastrophic failure of the system. Repair rates are general functions of the time spent. All the transition rates are constant except …


Optimal Correction Of Infeasible System In Linear Equality Via Genetic Algorithm, S. Ketabchi, H. Moosaei, S. Fallahi Dec 2010

Optimal Correction Of Infeasible System In Linear Equality Via Genetic Algorithm, S. Ketabchi, H. Moosaei, S. Fallahi

Applications and Applied Mathematics: An International Journal (AAM)

This work is focused on the optimal correction of infeasible system of linear equality. In this paper, for correcting this system, we will make the changes just in the coefficient matrix by using l 􀬶 norm and show that solving this problem is equivalent to solving a fractional quadratic problem. To solve this problem, we use the genetic algorithm. Some examples are provided to illustrate the efficiency and validity of the proposed method.


Differential Transform Method For Nonlinear Parabolic-Hyperbolic Partial Differential Equations, J. Biazar, M. Eslami, M. R. Islam Dec 2010

Differential Transform Method For Nonlinear Parabolic-Hyperbolic Partial Differential Equations, J. Biazar, M. Eslami, M. R. Islam

Applications and Applied Mathematics: An International Journal (AAM)

In the present paper an analytic solution of non-linear parabolic-hyperbolic equations is deduced with the help of the powerful differential transform method (DTM). To illustrate the capability and efficiency of the method four examples for different cases of the equation are solved. The method can easily be applied to many problems and is capable of reducing the size of computational work.


Concomitants Of Upper Record Statistics For Bivariate Pseudo–Weibull Distribution, Muhammad Ahsanullah, Saman Shahbaz, Muhammad Qaiser Shahbaz, Muhammad Mohsin Dec 2010

Concomitants Of Upper Record Statistics For Bivariate Pseudo–Weibull Distribution, Muhammad Ahsanullah, Saman Shahbaz, Muhammad Qaiser Shahbaz, Muhammad Mohsin

Applications and Applied Mathematics: An International Journal (AAM)

In this paper the Bivariate Pseudo–Weibull distribution has been defined as a compound distribution of two random variables to model the failure rate of component reliability. The distribution of r–th concomitant and joint distribution of r–th and s–th concomitant of record statistics of the resulting distribution have been derived. Single and product moments alongside the correlation coefficient have also been obtained. Recurrence relation for the single moments has also been obtained for the resulting distributions.


Bianchi Type I Magnetized Cosmological Model In Bimetric Theory Of Gravitation, M. S. Borkar, S. S. Charjan Dec 2010

Bianchi Type I Magnetized Cosmological Model In Bimetric Theory Of Gravitation, M. S. Borkar, S. S. Charjan

Applications and Applied Mathematics: An International Journal (AAM)

In this paper, we attempt to construct a Bianchi Type I magnetized cosmological model in Rosen’s bimetric theory of gravitation by using the techniques of Letelier and Stachel under the condition that ABCn , where n  0 in Rosen’s field equations. The physical and geometrical significance of the model are discussed. It is important to note the added dimension of this paper include the introduction of a magnetic field on the model. Prior to this, all it has been is a vacuum model in bimetric gravitation.


Approximate Analytical Solutions For Fractional Space- And Time- Partial Differential Equations Using Homotopy Analysis Method, Subir, Das, R. Kumar, P. K. Gupta, Hossein Jafari Dec 2010

Approximate Analytical Solutions For Fractional Space- And Time- Partial Differential Equations Using Homotopy Analysis Method, Subir, Das, R. Kumar, P. K. Gupta, Hossein Jafari

Applications and Applied Mathematics: An International Journal (AAM)

This article presents the approximate analytical solutions of first order linear partial differential equations (PDEs) with fractional time- and space- derivatives. With the aid of initial values, the explicit solutions of the equations are solved making use of reliable algorithm like homotopy analysis method (HAM). The speed of convergence of the method is based on a rapidly convergent series with easily computable components. The fractional derivatives are described in Caputo sense. Numerical results show that the HAM is easy to implement and accurate when applied to space- time- fractional PDEs.


Call For Articles Dec 2010

Call For Articles

Sci-Tech News

No abstract provided.


Conference Report From Bonnie Hilditch International Librarian Award Winner, Shantanu Ganguly Ph.D. Dec 2010

Conference Report From Bonnie Hilditch International Librarian Award Winner, Shantanu Ganguly Ph.D.

Sci-Tech News

No abstract provided.


Division Officers And Boards Dec 2010

Division Officers And Boards

Sci-Tech News

No abstract provided.


The Distribution And Reproductive Success Of The Western Snowy Plover Along The Oregon Coast - 2010, David J. Lauten, Kathleen J. Castelein, J. Daniel Farrar, Adam A. Kotaich, Eleanor P. Gaines Dec 2010

The Distribution And Reproductive Success Of The Western Snowy Plover Along The Oregon Coast - 2010, David J. Lauten, Kathleen J. Castelein, J. Daniel Farrar, Adam A. Kotaich, Eleanor P. Gaines

Institute for Natural Resources Publications

From 8 April – 27 September 2010 we monitored the distribution, abundance and productivity of the federally Threatened Western Snowy Plover (Charadrius alexandrinus nivosus) along the Oregon coast. From north to south, we surveyed and monitored plover activity at Sutton Beach, Siltcoos River estuary, the Dunes Overlook, North Tahkenitch Creek, Tenmile Creek, Coos Bay North Spit, Bandon Beach, New River, and Floras Lake. Our objectives for the Oregon coastal population in 2010 were to: 1) estimate the size of the adult Snowy Plover population, 2) locate plover nests, 3) continue selective use of mini-exclosures (MEs) to protect nests …


High Flow Air Sampling For Field Detection Using Gas Chromatography-Mass Spectrometry, Jacolin Ann Murray Dec 2010

High Flow Air Sampling For Field Detection Using Gas Chromatography-Mass Spectrometry, Jacolin Ann Murray

Theses and Dissertations

The ability to rapidly detect and identify hazardous analytes in the field has become increasingly important. One of the most important analytical detection methods in the field is gas chromatography-mass spectrometry (GC-MS). In this work, a hand-portable GC-MS system is described that contains a miniature toroidal ion trap mass analyzer and a low thermal mass GC. The system is self-contained within the dimensions of 47 x 36 x 18 cm and weighs less than 13 kg. Because the instrument has a small footprint, it was used as the detector for an automated near-real-time permeation testing system. In permeation testing, materials …


The Hydrology Of The Carroll Cave-Toronto Springs System: Identifying And Examining Source Mixing Through Dye Tracing, Geochemical Monitoring, Seepage Runs, And Statistical Methods, Benjamin Verlinden Miller Dec 2010

The Hydrology Of The Carroll Cave-Toronto Springs System: Identifying And Examining Source Mixing Through Dye Tracing, Geochemical Monitoring, Seepage Runs, And Statistical Methods, Benjamin Verlinden Miller

Masters Theses & Specialist Projects

In karst areas relationships between activities occurring on the surface and the overall health of the subsurface environment are often highly interconnected. However, the complex nature of karst flow systems can often make identification of these connections difficult. Carroll Cave, a large stream cave system located in the central Missouri Ozarks, is known for its biological and speleological significance. A dye tracing project to delineate a Carroll Cave recharge area through dye tracing has identified an area of 18.5 km2 which contributes water to the cave. The water from Thunder River within Carroll Cave was positively traced to eight springs …


Phosphorus Export From A Restored Wetland Ecosystem In Response To Natural And Experimental Hydrologic Fluctuations, Marcelo Ardón, Shaena Montanari, Jennifer L. Morse, Martin W. Doyle, Emily S. Bernhardt Dec 2010

Phosphorus Export From A Restored Wetland Ecosystem In Response To Natural And Experimental Hydrologic Fluctuations, Marcelo Ardón, Shaena Montanari, Jennifer L. Morse, Martin W. Doyle, Emily S. Bernhardt

Environmental Science and Management Faculty Publications and Presentations

Wetland restoration is a commonly used approach to reduce nutrient loading to freshwater and coastal ecosystems, with many wetland restoration efforts occurring in former agricultural fields. Restored wetlands are expected to be effective at retaining or removing both nitrogen and phosphorus (P), yet restoring wetland hydrology to former agricultural fields can lead to the release of legacy fertilizer P. Here, we examined P cycling and export following rewetting of the Timberlake Restoration Project, a 440 ha restored riverine wetland complex in the coastal plain of North Carolina. We also compared P cycling within the restored wetland to two minimally disturbed …


A Genetic Algorithm For Multiobjective Hard Scheduling Optimization, Elías Niño, Carlos Ardila, Alfredo J. Perez, Yexid Donoso Dec 2010

A Genetic Algorithm For Multiobjective Hard Scheduling Optimization, Elías Niño, Carlos Ardila, Alfredo J. Perez, Yexid Donoso

Computer Science Faculty Publications

This paper proposes a genetic algorithm for multiobjective scheduling optimization based in the object oriented design with constrains on delivery times, process precedence and resource availability. Initially, the programming algorithm (PA) was designed and implemented, taking into account all constraints mentioned. This algorithm’s main objective is, given a sequence of production orders, products and processes, calculate its total programming cost and time.
Once the programming algorithm was defined, the genetic algorithm (GA) was developed for minimizing two objectives: delivery times and total programming cost. The stages defined for this algorithm were: selection, crossover and mutation. During the first stage, the …


Optimal Designs Approach To Portfolio Selection, Etukudo A. I. Dec 2010

Optimal Designs Approach To Portfolio Selection, Etukudo A. I.

CBN Journal of Applied Statistics (JAS)

In order to obtain the best tradeoff between risk and return, optimization algorithms are particularly useful in asset allocation in a portfolio mix. Such algorithms and proper solution techniques are very essential to investors in order to circumvent distress in business outfits. In this paper, we show that by minimizing the total variance of the portfolio involving stocks in two Nigerian banks which is a measure of risk, optimal allocation of investible funds to the portfolio mix is obtained. A completely new solution technique – modified super convergent line series algorithm which makes use of the principles of optimal designs …


Factors, Preventions And Correction Methods For Non-Response In Sample Surveys, Godwin Nwanzu Amahi Dec 2010

Factors, Preventions And Correction Methods For Non-Response In Sample Surveys, Godwin Nwanzu Amahi

CBN Journal of Applied Statistics (JAS)

Missing survey data occur because of unit and item non-response. This is practically independent of the method of data collection. As a result of the bias that non-response sometimes introduces in survey estimates, identifying factors that promote it, and taking measures of prevention and correction methods are clearly necessary. The standard method to compensate for unit non-response is by weighting adjustment, while item non-responses are handled by some form of imputation. This paper reviews factors that give rise to nonresponse and the corresponding methods used for its prevention and control. It also discusses their properties.


Is The Stock Market A Leading Indicator Of Economic Activity In Nigeria?, Alvan E. Ikoku Dec 2010

Is The Stock Market A Leading Indicator Of Economic Activity In Nigeria?, Alvan E. Ikoku

CBN Journal of Applied Statistics (JAS)

In an effort to address the lacuna in leading indicator studies of African economies and Nigeria in particular, this paper examines the causal relationships among stock market prices, real GDP and the index of industrial production in Nigeria, using quarterly data from 1984Q1 to 2008Q4. Granger causality tests indicate bidirectional causality between stock prices and GDP but no causality between stock prices and industrial production or between GDP and industrial production. Stock prices and GDP are found to be cointegrated, leading to the estimation of vector error correction models. Out-of-sample forecasts constructed with AR(1), ARIMA, structural ARIMA, and VEC models …


Folate Receptor-Targeted Delivery Of Small Interfering Rna To Cancer Cells, Yilin Zhang Dec 2010

Folate Receptor-Targeted Delivery Of Small Interfering Rna To Cancer Cells, Yilin Zhang

Dissertations

The vitamin folic acid (folate, FA) has been extensively explored as a targeting ligand to deliver a variety of diagnostic/prognostic/therapeutic agents into various tumors through the assistance of its receptor – the folate receptor (FR). FR is over-expressed in many types of human cancer and can mediate internalization of FA-conjugates through an endocytic pathway. The discovery of small interfering RNA (siRNA), which is cable of inducing potent gene silencing in a sequence-specific manner, provides an excellent molecular tool to suppress aberrant gene expression in malignancies, and therefore siRNA has the potential to revolutionize cancer therapeutics. Towards the goal of developing …


Particulate Suspension Blood Flow Through A Stenosed Catheterized Artery, V. P. Srivastava, Rochana Vishnoi, Poonam Sinha Dec 2010

Particulate Suspension Blood Flow Through A Stenosed Catheterized Artery, V. P. Srivastava, Rochana Vishnoi, Poonam Sinha

Applications and Applied Mathematics: An International Journal (AAM)

The flow of blood through a narrow catheterized artery with an overlapping stenosis has been investigated. To account for the presence of red cells, blood has been represented by a macroscopic two-phase model (i.e., a suspension of erythrocytes in plasma). The expression for the flow characteristics-the flow rate, the impedance (resistance to flow), the wall shear stress in the stenotic region, the shear stresses at the stenosis two throats and at critical height of the stenosis, has been derived. It is found that the impedance increases with the catheter size, with the hematocrit and also with the stenosis size (height …


Duality In Fuzzy Linear Programming With Symmetric Trapezoidal Numbers, S. H. Nasseri, E. Ebrahimnejad, S. Mizuno Dec 2010

Duality In Fuzzy Linear Programming With Symmetric Trapezoidal Numbers, S. H. Nasseri, E. Ebrahimnejad, S. Mizuno

Applications and Applied Mathematics: An International Journal (AAM)

Linear programming problems with trapezoidal fuzzy numbers have recently attracted much interest. Various methods have been developed for solving these types of problems. Here, following the work of Ganesan and Veeramani and using the recent approach of Mahdavi-Amiri and Nasseri, we introduce the dual of the linear programming problem with symmetric trapezoidal fuzzy numbers and establish some duality results. The results will be useful for post optimality analysis.