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Full-Text Articles in Physical Sciences and Mathematics

Effect Of Variability In Rainfall Characteristics On Maize Yield In Gboko, Nigeria, Emmanuel Msughter Adamgbe, Fanan Ujoh Ph.D Sep 2013

Effect Of Variability In Rainfall Characteristics On Maize Yield In Gboko, Nigeria, Emmanuel Msughter Adamgbe, Fanan Ujoh Ph.D

Dr. Fanan Ujoh

The study examines the impact of variability in rainfall characteristics on maize yield in a tropical setting. The study design involves the collection and analyses of data on rainfall characteristics and maize yield at Gboko LGA in Benue State, Nigeria. The methodology adopted is the use of archival data on rainfall and maize yield for 30 years, collected from the Agro-Meteorological Unit and Farm Department of Akperan Orshi College of Agriculture, Yandev (AOCAY). The data was analyzed using mean, correlation and regression analysis to establish cause and effect relationship be- tween rainfall characteristics and maize yield at the study area. …


The Contribution Of Fe (Iii) And Humic Acid Reduction To Ecosystem Respiration In Drained Thaw Lake Basins Of The Arctic Coastal Plain, David A. Lipson, Ted K. Raab, Dominic Goria, Jaime Zlamal May 2013

The Contribution Of Fe (Iii) And Humic Acid Reduction To Ecosystem Respiration In Drained Thaw Lake Basins Of The Arctic Coastal Plain, David A. Lipson, Ted K. Raab, Dominic Goria, Jaime Zlamal

Ted K. Raab

Previous research showed that anaerobic respiration using iron (Fe) oxides as terminal electron acceptor contributed substantially to ecosystem respiration (ER) in a drained thaw lake basin (DTLB) on the Arctic coastal plain. As DTLB age, the surface organic layer thickens, progressively burying the Fe-rich mineral layers. We therefore hypothesized that Fe (III) availability and Fe reduction would decline with basin age. We studied four DTLB across an age gradient, comparing seasonal changes in the oxidation state of dissolved and extractable Fe pools and the estimated contribution of Fe reduction to ER. The organic layer thickness did not strictly increase with …


Semi-Automated Classification Of Gray Scale Aerial Photographs Using Geographic Object Based Image Analysis (Geobia) Technique, Ahmed Harb Rabia, Fabio Terribile Apr 2013

Semi-Automated Classification Of Gray Scale Aerial Photographs Using Geographic Object Based Image Analysis (Geobia) Technique, Ahmed Harb Rabia, Fabio Terribile

Ahmed Harb Rabia A.H. Rabia

Aerial photography is an important source of high resolution remotely sensed data. Before 1970, aerial photographs were the only remote sensing data source for land use and land cover classification. Using these old aerial photographs improve the final output of land use and land cover change detection. However, classic techniques of aerial photographs classification like manual interpretation or screen digitization require great experience, long processing time and vast effort. A new technique needs to be developed in order to reduce processing time and effort and to give better results. Geographic object based image analysis (GEOBIA) is a newly developed area …


Land Suitability Analysis For Policy Making Assistance: A Gis Based Land Suitability Comparison Between Surface And Drip Irrigation Systems, Ahmed Harb Rabia A.H. Rabia, H. Figueredo, T. L. Huong, B. A. A. Lopez,, H. W. Solomon, V. Alessandro Mar 2013

Land Suitability Analysis For Policy Making Assistance: A Gis Based Land Suitability Comparison Between Surface And Drip Irrigation Systems, Ahmed Harb Rabia A.H. Rabia, H. Figueredo, T. L. Huong, B. A. A. Lopez,, H. W. Solomon, V. Alessandro

Ahmed Harb Rabia A.H. Rabia

Land suitability assessment for irrigation is a very important tool not only in terms of agriculture development planning, but also to overcome the global problem of water scarcity. The aim of this study is to spatially evaluate land suitability of the study area, Kilte Awulaelo district in Ethiopia, for surface and drip irrigation methods based on GIS and remote sensing approaches. This work has been done as a part of the 29th Course Professional Master in Istituto Agronomico per l’Oltremare, Florence, Italy. Final suitability maps show the irregularity of suitability classes’ distribution over the study area. Results show that only …


Introducing A New Parametric Concept For Land Suitability Assessment, Ahmed Harb Rabia Mar 2013

Introducing A New Parametric Concept For Land Suitability Assessment, Ahmed Harb Rabia

Ahmed Harb Rabia A.H. Rabia

In an ecosystem, there is need to establish the quantity and quality of resources and their suitability for a certain range of land uses in order to assure its future productivity and sustainability of biodiversity. Parametric methods are widely used for land suitability evaluation. A new parametric concept “equation” of land suitability evaluation has been proposed to improve results of land suitability evaluation. Land suitability assessment for wheat production was conducted in order to compare results of the suggest method with classical parametric methods. Organic matter, CaCO3, pH, Slope, texture, drainage, depth, EC and altitude were recognized as factors affecting …


Cfp: Handbook Of Research On Technological Applications And Innovation For Economic Development, Deogratias Harorimana Mr Mar 2013

Cfp: Handbook Of Research On Technological Applications And Innovation For Economic Development, Deogratias Harorimana Mr

Dr Deogratias Harorimana

The innovation in the 21st century goes significantly beyond the high-tech picture driven by small or large industry clusters in a specific region-typically Silicon Valley and M4Corridor. The future of innovation will lie within knowledge management and seamless technological applications. These will be supported by planned funding strategies, possibly with clients as drivers of the innovation. This view seems to be supported by the UK government “Technology and Innovation Futures” (2011); the USA government (2011), study into which leading scholars concede that the future innovation and technological applications for economic growth will include products and processes, improvements in areas such …


A Study Of Mexican Free-Tailed Bat Chirp Syllables: Bayesian Functional Mixed Modeling Of Nonstationary Time Series Data With Time-Dependent Spectra, Josue G. Martinez, Kirsten M. Bohn, Raymond J. Carroll, Jeffrey S. Morris Feb 2013

A Study Of Mexican Free-Tailed Bat Chirp Syllables: Bayesian Functional Mixed Modeling Of Nonstationary Time Series Data With Time-Dependent Spectra, Josue G. Martinez, Kirsten M. Bohn, Raymond J. Carroll, Jeffrey S. Morris

Jeffrey S. Morris

We describe a new approach to analyze chirp syllables of free-tailed bats from two regions of Texas in which they are predominant: Austin and College Station. Our goal is to characterize any systematic regional differences in the mating chirps and assess whether individual bats have signature chirps. The data are analyzed by modeling spectrograms of the chirps as responses in a Bayesian functional mixed model. Given the variable chirp lengths, we compute the spectrograms on a relative time scale interpretable as the relative chirp position, using a variable window overlap based on chirp length. We use 2D wavelet transforms to …


Travelling In Cuba, Fathi Habashi Feb 2013

Travelling In Cuba, Fathi Habashi

Fathi Habashi

Contact with Cuban scientists was established in 1986 when two researchers from Centro de Investigaciones para Industria Minero Metalurgica in Havana visited Laval University to get acquainted with research activities in the area of extractive metallurgy. This was followed in early 1987 by two more researchers from the same centre. Invitations were then received in late 1987, 1989, and 2008 to visit the nickel refineries in Cuba and to hold seminars at the University of Havana. The present report outlines these activities.


Global Quantitative Assessment Of The Colorectal Polyp Burden In Familial Adenomatous Polyposis Using A Web-Based Tool, Patrick M. Lynch, Jeffrey S. Morris, William A. Ross, Miguel A. Rodriguez-Bigas, Juan Posadas, Rossa Khalaf, Diane M. Weber, Valerie O. Sepeda, Bernard Levin, Imad Shureiqi Jan 2013

Global Quantitative Assessment Of The Colorectal Polyp Burden In Familial Adenomatous Polyposis Using A Web-Based Tool, Patrick M. Lynch, Jeffrey S. Morris, William A. Ross, Miguel A. Rodriguez-Bigas, Juan Posadas, Rossa Khalaf, Diane M. Weber, Valerie O. Sepeda, Bernard Levin, Imad Shureiqi

Jeffrey S. Morris

Background: Accurate measures of the total polyp burden in familial adenomatous polyposis (FAP) are lacking. Current assessment tools include polyp quantitation in limited-field photographs and qualitative total colorectal polyp burden by video.

Objective: To develop global quantitative tools of the FAP colorectal adenoma burden.

Design: A single-arm, phase II trial.

Patients: Twenty-seven patients with FAP.

Intervention: Treatment with celecoxib for 6 months, with before-treatment and after-treatment videos posted to an intranet with an interactive site for scoring.

Main Outcome Measurements: Global adenoma counts and sizes (grouped into categories: less than 2 mm, 2-4 mm, and greater than 4 mm) were …


Fractal Approach To Heat Transfer In Silkworm Cocoon Hierarchy, Dong-Dong Fei, Fu-Juan Liu, Qiu-Na Cui, Ji-Huan He Jan 2013

Fractal Approach To Heat Transfer In Silkworm Cocoon Hierarchy, Dong-Dong Fei, Fu-Juan Liu, Qiu-Na Cui, Ji-Huan He

Ji-Huan He

Silkworm cocoon has a complex hierarchic structure with discontinuity. In this paper, heat transfer through the silkworm cocoon is studied using fractal theory. The fractal approach has been successfully applied to explain the fascinating phenomenon of cocoon survival under extreme temperature environment. A better understanding of heat transfer mechanisms for the cocoon could be beneficial to the design of biomimetic clothes for special applications.


Microfabricated Nanotopological Surfaces For Study Of Adhesion-Dependent Cell Mechanosensitivity, Weiqiang Chen, Yubing Sun, Jianping Fu Jan 2013

Microfabricated Nanotopological Surfaces For Study Of Adhesion-Dependent Cell Mechanosensitivity, Weiqiang Chen, Yubing Sun, Jianping Fu

Weiqiang Chen

Cells exhibit high sensitivity and diverse responses to the intrinsic nanotopography of the extracellular matrix through their nanoscale cellular sensing machinery. A simple microfabrication method for precise control and spatial patterning of the local nanoroughness on glass surfaces by using photolithography and reactive ion etching is reported. It is demonstrated that local nanoroughness as a biophysical cue could regulate a diverse array of NIH/3T3 fi broblast behaviors, including cell morphology, adhesion, proliferation, migration, and cytoskeleton contractility. The capability to control and further predict cellular responses to nanoroughness might suggest novel methods for developing biomaterials mimicking nanotopographic structures in vivo for …


Surface-Micromachined Microfiltration Membranes For Efficient Isolation And Functional Immunophenotyping Of Subpopulations Of Immune Cells, Weiqiang Chen, Nien-Tsu Huang, Boram Oh, Raymond H. W. Lam, Rong Fan, Timothy T. Cornell, Thomas P. Shanley, Katsuo Kurabayashi, Jianping Fu Jan 2013

Surface-Micromachined Microfiltration Membranes For Efficient Isolation And Functional Immunophenotyping Of Subpopulations Of Immune Cells, Weiqiang Chen, Nien-Tsu Huang, Boram Oh, Raymond H. W. Lam, Rong Fan, Timothy T. Cornell, Thomas P. Shanley, Katsuo Kurabayashi, Jianping Fu

Weiqiang Chen

An accurate measurement of the immune status in patients with immune system disorders is critical in evaluating the stage of diseases and tailoring drug treatments. The functional cellular immunity test is a promising method to establish the diagnosis of immune dysfunctions. The conventional functional cellular immunity test involves measurements of the capacity of peripheral blood mononuclear cells to produce pro-inflammatory cytokines when stimulated ex vivo. However, this “bulk” assay measures the overall reactivity of a population of lymphocytes and monocytes, making it difficult to pinpoint the phenotype or real identity of the reactive immune cells involved. In this research, we …


Comparative Study Of Biological And Artificial Neural Networks, O S. Eluyode, Dr. Dipo Theophilus Akomolafe Mbcs, Mncs, Mcpn, Jan 2013

Comparative Study Of Biological And Artificial Neural Networks, O S. Eluyode, Dr. Dipo Theophilus Akomolafe Mbcs, Mncs, Mcpn,

Dr. Dipo Theophilus Akomolafe MBCS, MNCS, MCPN,

In this research project, the features of biological and artificial neural networks were studied by reviewing the existing works of authorities in print and electronics on biological and artificial neural networks. The features were then assessed and evaluated and comparative analysis of the two networks was carried out. The metrics such as structures, layers, size and functional capabilities of neurons, learning capabilities, style of computation, processing elements, processing speed, connections, strength, information storage, information transmission, communication media selection, signal transduction and fault tolerance were used as basis for comparison. A major finding in the research showed that artificial neural networks …


Classification Of The Alterations Of Beaver Dams To Headwater Streams In Northeastern Connecticut, U.S.A., Denise Burchsted, Melinda D. Daniels Jan 2013

Classification Of The Alterations Of Beaver Dams To Headwater Streams In Northeastern Connecticut, U.S.A., Denise Burchsted, Melinda D. Daniels

Denise Burchsted

Of the many types of barriers to water flow, beaver dams are among the smallest, typically lasting less than a decade and rarely exceeding 1.5 m in height. They are also among the most frequent and common obstructions in rivers, with a density often exceeding ten dams per km, a frequency of construction within a given network on a time scale of years, and a historic extent covering most of North America. Past quantification of the geomorphologic impact of beaver dams has primarily been limited to local impacts within individual impoundments and is of limited geographic scope. To assess the …