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Full-Text Articles in Physical Sciences and Mathematics

Small Scale Changes In Zooplankton Community In Relation To Stratification And Phytoplankton Thin Layers, Adam T. Greer Feb 2012

Small Scale Changes In Zooplankton Community In Relation To Stratification And Phytoplankton Thin Layers, Adam T. Greer

Adam T. Greer

Gelatinous zooplankton represent a poorly understood component of marine food webs in part because of difficulties estimating abundance using traditional net sampling techniques. The degree of vertical patchiness can influence the trophic impact of jellies, and the biophysical drivers of their distributions remain unknown. Using a towed In Situ Ichthyoplankton Imaging System (ISIIS), we examined the changes in jelly distributions during upwelling and relaxation events in Monterey Bay, CA. Sampling began at the end of a 12 d stretch of upwelling favorable winds. The first day of sampling was marked by a thin layer of high chlorophyll fluorescence and intense …


Using The Case Study Methodology In Teaching, Deogratias Harorimana Mr Jan 2012

Using The Case Study Methodology In Teaching, Deogratias Harorimana Mr

Dr Deogratias Harorimana

This paper reviews the Why, How, to use the Case Study Methods in MBA teaching. The Presentation was prepared for and delivered as part of MBA students induction Programme in the Graduate School of Business.


Socio-Economic Effects Of Demolishing Squatter Settlements And Illegal Structures In Abuja Metropolis, Federal Capital Territory, Nigeria, Ishaku Iy Mallo Phd, Victor G. Obasanya Jan 2012

Socio-Economic Effects Of Demolishing Squatter Settlements And Illegal Structures In Abuja Metropolis, Federal Capital Territory, Nigeria, Ishaku Iy Mallo Phd, Victor G. Obasanya

Confluence Journal Environmental Studies (CJES), Kogi State University, Nigeria

Abuja the Federal Capital Territory and study area is located between latitudes 8o25’ and 9o25’ North of the Equator and longitudes 6o45’ and 7o45’ East of the Greenwich Meridian. The study was carried out in Abuja Phase 1, and it is aimed at highlighting various socioeconomic effects of demolition of illegal structures and informal or squatter settlements on the people within the study area. Data was collected through reconnaissance survey, personal interviews with respondents, and a well laid out questionnaire. The results indicate that the demolition exercise embarked upon by the authorities in the Federal Capital Territory was a response …


Rainfall Variability And Crop Zones Classification For The Federal Capital Territory, Nigeria, Shaibu M. Hassan Phd Jan 2012

Rainfall Variability And Crop Zones Classification For The Federal Capital Territory, Nigeria, Shaibu M. Hassan Phd

Confluence Journal Environmental Studies (CJES), Kogi State University, Nigeria

This study aims at analyzing agro-climatological parameters and establishing a link between some selected agro-climatological indices and sustainability of agricultural production in the Federal Capital Territory (FCT). Two sets of data, climatic and crop yield data were collected and subjected to various agro-climatological analyses. Agro-climatological analyses include the derivation of Onset, Cessation and Length of Rainy Season (LRS), Seasonality Index, Drought Index and Precipitation Periodicity Index. The statistical analyses include monthly and annual means, deviation from the mean, trend line. The result of moisture index in line with crops optimum moisture requirement was used to classify the Territory into agro-climatic …


Statistical Methods For Proteomic Biomarker Discovery Based On Feature Extraction Or Functional Modeling Approaches, Jeffrey S. Morris Jan 2012

Statistical Methods For Proteomic Biomarker Discovery Based On Feature Extraction Or Functional Modeling Approaches, Jeffrey S. Morris

Jeffrey S. Morris

In recent years, developments in molecular biotechnology have led to the increased promise of detecting and validating biomarkers, or molecular markers that relate to various biological or medical outcomes. Proteomics, the direct study of proteins in biological samples, plays an important role in the biomarker discovery process. These technologies produce complex, high dimensional functional and image data that present many analytical challenges that must be addressed properly for effective comparative proteomics studies that can yield potential biomarkers. Specific challenges include experimental design, preprocessing, feature extraction, and statistical analysis accounting for the inherent multiple testing issues. This paper reviews various computational …


Integrative Bayesian Analysis Of High-Dimensional Multi-Platform Genomics Data, Wenting Wang, Veerabhadran Baladandayuthapani, Jeffrey S. Morris, Bradley M. Broom, Ganiraju C. Manyam, Kim-Anh Do Jan 2012

Integrative Bayesian Analysis Of High-Dimensional Multi-Platform Genomics Data, Wenting Wang, Veerabhadran Baladandayuthapani, Jeffrey S. Morris, Bradley M. Broom, Ganiraju C. Manyam, Kim-Anh Do

Jeffrey S. Morris

Motivation: Analyzing data from multi-platform genomics experiments combined with patients’ clinical outcomes helps us understand the complex biological processes that characterize a disease, as well as how these processes relate to the development of the disease. Current integration approaches that treat the data are limited in that they do not consider the fundamental biological relationships that exist among the data from platforms.

Statistical Model: We propose an integrative Bayesian analysis of genomics data (iBAG) framework for identifying important genes/biomarkers that are associated with clinical outcome. This framework uses a hierarchical modeling technique to combine the data obtained from multiple platforms …


Optimal Switching Control Of A Fed-Batch Fermentation Process, Chongyang Liu, Zhaohua Gong, Enmin Feng, Hongchao Yin Jan 2012

Optimal Switching Control Of A Fed-Batch Fermentation Process, Chongyang Liu, Zhaohua Gong, Enmin Feng, Hongchao Yin

Chongyang Liu

Considering the hybrid nature in fed-batch culture of glycerol biconversion to 1,3-propanediol (1,3-PD) by Klebsiella pneumoniae, we propose a state-based switching dynamical system to describe the fermentation process. To maximize the concentration of 1,3-PD at the terminal time, an optimal switching control model subject to our proposed switching system and constraints of continuous state inequality and control function is presented. Because the number of the switchings is not known a priori, we reformulate the above optimal control problem as a two-level optimization problem. An optimization algorithm is developed to seek the optimal solution on the basis of a heuristic approach …


Nonlinear Dynamical Systems Of Fed-Batch Fermentation And Their Optimal Control, Chongyang Liu, Zhaohua Gong, Enmin Feng, Hongchao Yin Jan 2012

Nonlinear Dynamical Systems Of Fed-Batch Fermentation And Their Optimal Control, Chongyang Liu, Zhaohua Gong, Enmin Feng, Hongchao Yin

Chongyang Liu

In this article, we propose a controlled nonlinear dynamical system with variable switching instants, in which the feeding rate of glycerol is regarded as the control function and the moments between the batch and feeding processes as switching instants, to formulate the fed-batch fermentation of glycerol bioconversion to 1,3-propanediol (1,3-PD). Some important properties of the proposed system and its solution are then discussed. Taking the concentration of 1,3-PD at the terminal time as the cost functional, we establish an optimal control model involving the controlled nonlinear dynamical system and subject to continuous state inequality constraints. The existence of the optimal …


Modeling And Parameter Identification Involving 3-Hydroxypropionaldehyde Inhibitory Effects In Glycerol Continuous Fermentation, Zhaohua Gong, Chongyang Liu, Yongsheng Yu Jan 2012

Modeling And Parameter Identification Involving 3-Hydroxypropionaldehyde Inhibitory Effects In Glycerol Continuous Fermentation, Zhaohua Gong, Chongyang Liu, Yongsheng Yu

Chongyang Liu

Mathematical modeling and parameter estimation are critical steps in the optimization of biotechnological processes. In the 1,3-propanediol (1,3-PD )production by glycerol fermentation process under anaerobic conditions, 3-hydroxypropionaldehyde (3-HPA) accumulation would arouse an irreversible cessation of the fermentation process. Considering 3-HPA inhibitions to cells growth and to activities of enzymes, we propose a novel mathematical model to describe glycerol continuous cultures. Some properties of the above model are discussed. On the basis of the concentrations of extracellular substances, a parameter identification model is established to determine the kinetic parameters in the presented system. Through the penalty function technique combined with an …


Optimal Control Of A Fed-Batch Fermentation Involving Multiple Feeds, Chongyang Liu, Zhaohua Gong, Zhaoyi Huo, Bangyu Shen Jan 2012

Optimal Control Of A Fed-Batch Fermentation Involving Multiple Feeds, Chongyang Liu, Zhaohua Gong, Zhaoyi Huo, Bangyu Shen

Chongyang Liu

A nonlinear dynamical system, in which the feed rates of glycerol and alkali are taken as the control functions, is first proposed to formulate the fed-batch culture of 1,3-propanediol (1,3-PD) production. To maximize the 1,3-PD concentration at the terminal time, a constrained optimal control model is then presented. A solution approach is developed to seek the optimal feed rates based on control vector parametrization method and improved differential evolution algorithm. The proposed methodology yielded an increase by 32.17% of 1,3-PD concentration at the terminal time.


Waste Recycling: Feasibility Of Saw Dust Based Spent Mushroom Substrate And Goat Manure In Vermicomposting, Adi Ainurzaman Jamaludin, Noor Zalina Mahmood, Noorlidah Abdullah Jan 2012

Waste Recycling: Feasibility Of Saw Dust Based Spent Mushroom Substrate And Goat Manure In Vermicomposting, Adi Ainurzaman Jamaludin, Noor Zalina Mahmood, Noorlidah Abdullah

Adi Ainurzaman Jamaludin

Vermicomposting for 140 days by using Lumbricus rubellus was conducted after 21 days of natural pre-composting. Five treatments in different ratio of goat manure: spent mushroom substrate were prepared as feed materials with four replicates for each treatment namely; 20:80 (TA), 40:60 (TB), 50:50 (TC), 60:40 (TD) and 80:20 (TE). As for control, each treatment without earthworm was prepared. On the basis of nutrient elements, goat manure and spent mushroom substrate can be decomposed through both methods of vermicomposting and natural composting. Findings of this study indicated that the higher usage of goat manure with longer duration resulted in the …


The Gatekeeper And The Knowledge Environment-Who They Are, How They Work Empirical Evidences From High-Tech Manufacturing And R&D Firms, Deogratias Harorimana Jan 2012

The Gatekeeper And The Knowledge Environment-Who They Are, How They Work Empirical Evidences From High-Tech Manufacturing And R&D Firms, Deogratias Harorimana

Dr Deogratias Harorimana

Purpose of the Study: The purpose of this study was to critically study the role of the Knowledge Gatekeeper within the manufacturing and high tech selected case studies and by explaining who they are, how they work and identify and analyse the barriers to knowledge creation and knowledge sharing. Methodology: The research was guided by an inductive approach with a multiple case study strategy. Research instruments included a questionnaire and interviews from respectively 105 and 40 respondents. Findings: In the African Manufacturing context, and in absence of sophisticated technologies and highly qualified personnel, technical knowledge can be obtained from organizational …


Review Of Economics Of Manamagement Information Systems, Deogratias Harorimana Sr Jan 2012

Review Of Economics Of Manamagement Information Systems, Deogratias Harorimana Sr

Dr Deogratias Harorimana

“Information technology is the "digital nervous system" of any business.” (Bill Gates, Chairman, Microsoft Corporation, 1997)

The way business is conducted in this era is phenomenal. Almost everything is a “click” away. The customers are satisfied, businesses are satisfied, Government is satisfied and the entire globe is gratified by the work of information technology (IT). This research discloses the several returns and shortcomings of IT, and how businesses use IT to realize their strategic goals.

The report presents discussion on two organisations, Dell Computer Corporation and Sydney Waters, which had a prosperous and disastrous implementation of IT systems respectively. The …


Using Mis To Deliver Essential Services:Case Of Healthcare Provision Support In Fiji, Deogratias Harorimana Sr Jan 2012

Using Mis To Deliver Essential Services:Case Of Healthcare Provision Support In Fiji, Deogratias Harorimana Sr

Dr Deogratias Harorimana

In comparison to other Pacific Island countries, Fiji’s health system is the most developed amongst Pacific Island countries (UNDP 2006) and has undergone significant change in the last decade. From 1999 – 2009, AusAid, a major donor to Fiji’s health system, has supported two stage health sector improvement programs. The first stage (1999 - 2003) was a management reform program designed to improve decision making by supporting a new model of decentralized management. The second phase (2004 – 2009) looked at improving governance, health systems performance, clinical outcomes and supported public health and infrastructure initiatives at the divisional level (WHO …


Impact Of Crm Systems On Organisational Performance: A Case Study Of Anz Bank, Deogratias Harorimana Sr Jan 2012

Impact Of Crm Systems On Organisational Performance: A Case Study Of Anz Bank, Deogratias Harorimana Sr

Dr Deogratias Harorimana

This paper reports case study results analysis of the ANZ Bank in the Pacific Region. The case study results show that ANZ has a well-established CRM system supporting its marketing and sales activities, but equally the results indicate mixed scenarios. A positive relationship between CRM to performance was established. That is, it has a positive contribution to the bank’s performance, both financial and non-financial. There is also negative feedback on the bank’s CRM system which illustrates that CRM system can also have negative consequences. CRM success is questionable from a stand-alone perspective. Although there are encouraging results from the use …


Kinetic Analytical Method For Determination Of Uric Acid In Human Urine Using Analyte Pulse Perturbation Technique, Zeljko D. Cupic Jan 2012

Kinetic Analytical Method For Determination Of Uric Acid In Human Urine Using Analyte Pulse Perturbation Technique, Zeljko D. Cupic

Zeljko D Cupic

No abstract provided.


Water Table Height And Microtopography Control Biogeochemical Cycling In An Arctic Coastal Tundra Ecosystem, David A. Lipson, Donatella Zona, Ted K. Raab, Francis Bozzolo, Marguerite Mauritz, Walter C. Oechel Jan 2012

Water Table Height And Microtopography Control Biogeochemical Cycling In An Arctic Coastal Tundra Ecosystem, David A. Lipson, Donatella Zona, Ted K. Raab, Francis Bozzolo, Marguerite Mauritz, Walter C. Oechel

Ted K. Raab

Drained thaw lake basins (DTLB’s) are the dominant land form of the Arctic Coastal Plain in northern Alaska. The presence of continuous permafrost prevents drainage and so water tables generally remain close to the soil surface, creating saturated, suboxic soil conditions. However, ice wedge polygons produce microtopographic variation in these landscapes, with raised areas such as polygon rims creating more oxic microenvironments. The peat soils in this ecosystem store large amounts of organic carbon which is vulnerable to loss as arctic regions continue to rapidly warm, and so there is great motivation to understand the controls over microbial activity in …


Pyrite. History, Chemistry, And Metallurgy, Fathi Habashi Jan 2012

Pyrite. History, Chemistry, And Metallurgy, Fathi Habashi

Fathi Habashi

The Book covers the history of pyrite - - how it was a strategic mineral necessary for the production of elemental sulfur needed for making gunpowder for military purposes and for the production of SO2 needed for making sulfuric acid for the chemical industry. Now its presence is a nuisance in tailings ponds. The book also covers the processing of pyrite containing gold, its chemistry and technology, the processing of pyrite cinder for the production of a variety of metals, and its behaviour towards autotrophic microorganisms.


James-Stein Estimation And The Benjamini-Hochberg Procedure, Debashis Ghosh Jan 2012

James-Stein Estimation And The Benjamini-Hochberg Procedure, Debashis Ghosh

Debashis Ghosh

For the problem of multiple testing, the Benjamini-Hochberg (B-H) procedure has become a very popular method in applications. Based on a spacings theory representation of the B-H procedure, we are able to motivate the use of shrinkage estimators for modifying the B-H procedure. Several generalizations in the paper are discussed, and the methodology is applied to real and simulated datasets.


Shrinkage In Adaptive Procedures For False Discovery Rate Estimation In Multiple Testing: Structure And Synthesis, Debashis Ghosh Jan 2012

Shrinkage In Adaptive Procedures For False Discovery Rate Estimation In Multiple Testing: Structure And Synthesis, Debashis Ghosh

Debashis Ghosh

There has been much interest in the study of adaptive estimation procedures for controlling the false discovery rate (FDR). In this article, we take the direct approach to estimation of FDR of Storey (2002) and show how it can reexpressed as a particular type of shrinkage estimator. This representation leads to natural conditions on finite-sample FDR control for a general class of shrinkage estimators. In addition, many previous proposals from the literature can be unified under this framework for which finite-sample FDR results can be developed. Some asymptotic results are also provided.


Landscape Management For Sustainable Supplies Of Bioenergy Feedstock And Enhanced Soil Quality, Douglas L. Karlen, David J. Muth Jr. Jan 2012

Landscape Management For Sustainable Supplies Of Bioenergy Feedstock And Enhanced Soil Quality, Douglas L. Karlen, David J. Muth Jr.

David J. Muth

Agriculture can simultaneously address global food, feed, fi ber, and energy challenges provided our soil, water, and air resources are not compromised in doing so. As we embark on the 19th Triennial Conference of the International Soil and Tillage Research Organization (ISTRO), I am pleased to proclaim that our members are well poised to lead these endeavors because of our comprehensive understanding of soil, water, agricultural and bio-systems engineering processes. The concept of landscape management, as an approach for integrating multiple bioenergy feedstock sources, including biomass residuals, into current crop production systems, is used as the focal point to show …


Improving Biomass Logistics Cost Within Agronomic Sustainability Constratints And Biomass Quality Targets, Kevin L. Kenney, J. Richard Hess, William A. Smith, David J. Muth Jr. Jan 2012

Improving Biomass Logistics Cost Within Agronomic Sustainability Constratints And Biomass Quality Targets, Kevin L. Kenney, J. Richard Hess, William A. Smith, David J. Muth Jr.

David J. Muth

Equipment manufacturers have made rapid improvements in biomass harvesting and handling equipment. These improvements have increased transportation and handling efficiencies due to higher biomass densities and reduced losses. Improvements in grinder efficiencies and capacity have reduced biomass grinding costs. Biomass collection efficiencies (the ratio of biomass collected to the amount available in the field) as high as 75% for crop residues and greater than 90% for perennial energy crops have also been demonstrated. However, as collection rates increase, the fraction of entrained soil in the biomass increases, and high biomass residue removal rates can violate agronomic sustainability limits. Advancements in …


Economics Of Residue Harvest: Regional Partnership Evaluation, David W. Archer, David J. Muth Jr., Jacob J. Jacobson, Douglas L. Karlen Jan 2012

Economics Of Residue Harvest: Regional Partnership Evaluation, David W. Archer, David J. Muth Jr., Jacob J. Jacobson, Douglas L. Karlen

David J. Muth

Economic analyses on the viability of corn (Zea mays, L.) stover harvest for bioenergy production have largely been based on simulation modeling. While some studies have utilized field research data, most field-based analyses have included a limited number of sites and a narrow geographic distribution. An Iowa case study is developed illustrating the use of data extracted from a database of geographically distributed field studies for a region-specific economic analysis. The analysis utilizes grain and residue yield and associated management information from two Iowa field research sites that are Sun Grant Regional Partnership locations associated with the Corn Stover Regional …