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Full-Text Articles in Physical Sciences and Mathematics

Global Effects Of Climate Change On Wildfire: Causal Relationships Of Fire, The Natural Environment And Human Activities, Lindon N. Pronto Dec 2011

Global Effects Of Climate Change On Wildfire: Causal Relationships Of Fire, The Natural Environment And Human Activities, Lindon N. Pronto

Lindon N Pronto

Climate change and human activity is significantly impacting the frequency and severity of wildfires across the globe. Although climate change and human population are the overarching factors affecting wildfires in the current dialogue, the issues are more complex and often not fully understood. These issues range from global temperature increases and severe drought cycles to the relatively new phenomenon of the wildland urban interface (WUI). This is the area where structures are integrated with or immediately surrounded by areas of moderate to high fire risk and are directly linked to fuel types and topographic features. Because climate change is such …


A Critical Review Of The Effectiveness Of Fiscal And Monetary Policies In The Pacific Island Countries (Pics) Between 1990-2010, Deogratias Harorimana Mr Oct 2011

A Critical Review Of The Effectiveness Of Fiscal And Monetary Policies In The Pacific Island Countries (Pics) Between 1990-2010, Deogratias Harorimana Mr

Dr Deogratias Harorimana

The purpose of this paper is to critically assess the effectiveness of Fiscal and Monetary Policies in the South Pacific Island Countries. The paper tracks down the economic growth for the last 20 years between 1990-2010, and drawing from key fiscal and monetary policies in place during the time under consideration, as well as specific interventions in the region, we find that: 1) While the South Pacific Island Countries (SPICs) particularly the six major economies (Solomon Islands, Fiji, Vanuatu, PNG, Samoa, Tonga) pursued fiscal and monetary policies for promoting growth and diversification of their economies, their fiscal policies relied heavily …


Assessment Of Organic And Inorganic Phosphorus In Soils Derived From Cretaceous Sediments And Basement Complex Soils Of Guinea Savannah Of Kogi State, North Central Nigeria, Sunday I. Amhakhian, H H. Isitekhale, Charles I. Oyewole Aug 2011

Assessment Of Organic And Inorganic Phosphorus In Soils Derived From Cretaceous Sediments And Basement Complex Soils Of Guinea Savannah Of Kogi State, North Central Nigeria, Sunday I. Amhakhian, H H. Isitekhale, Charles I. Oyewole

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

A pot experiment was carried out using 20 surface soils (0-15cm depth) in 2008 to assess soil organic phosphorus and some fraction of inorganic phosphorus in other to know their availability in the soils of the studied area and also work have not been done in this areas in respect to organic and in-organic phosphorus. The experiment was conducted using 20 soils 10 from each geological formation (Cretaceous sediments and Basement complex soils), respectively. The mean organic phosphorus of 63.51 mgkg 1 soil was obtained for Cretaceous sediment soils and 158.54 mgkg 1 soil for the basement complex soils respectively. …


Development Of Functional Indices Of Facility Occurrence Towards The Distribution Of Social Services In Lagos Island Nigeria., Augustus O. Atubi Aug 2011

Development Of Functional Indices Of Facility Occurrence Towards The Distribution Of Social Services In Lagos Island Nigeria., Augustus O. Atubi

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

Proper coordination of transport and public facilities provision is vital to any balanced regional development strategy. The central aim of this study, therefore, is to find out what the relationship is between access to the transport network and the provision of functional indices of facility occurrence towards the distribution of social services in Lagos Island, Nigeria. In particular it seeks to find out areas that have below or above average level of facility occurrences relative to the level of accessibility. However, a pair wise correlation matrix of the eleven (11) variables employed in the index construction was carried out. The …


The Use Of Imputed Values In The Meta-Analysis Of Genome-Wide Association Studies., Shuo Jiao, Li Hsu, Carolyn Hutter, Ulrike Peters Jul 2011

The Use Of Imputed Values In The Meta-Analysis Of Genome-Wide Association Studies., Shuo Jiao, Li Hsu, Carolyn Hutter, Ulrike Peters

Shuo Jiao

In genome-wide association studies (GWAS), it is a common practice to impute the genotypes of untyped single nucleotide polymorphism (SNP) by exploiting the linkage disequilibrium structure among SNPs. The use of imputed genotypes improves genome coverage and makes it possible to perform meta-analysis combining results from studies genotyped on different platforms. A popular way of using imputed data is the "expectation-substitution" method, which treats the imputed dosage as if it were the true genotype. In current practice, the estimates given by the expectation-substitution method are usually combined using inverse variance weighting (IVM) scheme in meta-analysis. However, the IVM is not …


Urban Climate And Challenges Of Tropical Cities, B E. Omogbai Jul 2011

Urban Climate And Challenges Of Tropical Cities, B E. Omogbai

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

This study examines the nature of urban climate, features and the challenges on the developing tropical cities in the 21st century. It argues that the use of principles of urban climate would help in providing comfortable living conditions and problem immune working environments for the inhabitants of tropical cities. The findings reveal that owing to poor environmental planning, inadequate geotechnical landscape surveys prior to the development of urban infrastructures, and non-adherence to the principles of urban climate, challenges of landscape degradation, excessive flooding of the built infrastructures, heat-island effects, and collapse of buildings have emerged. Suggested measures to avert these …


Detecting Changes In Landuse/Cover Of Umuahia, South-Eastern Nigeria Using Remote Sensing And Gis Techniques, Fanan Ujoh, Olarewaju Oluseyi Ifatimehin, Adams Ndalai Baba Jul 2011

Detecting Changes In Landuse/Cover Of Umuahia, South-Eastern Nigeria Using Remote Sensing And Gis Techniques, Fanan Ujoh, Olarewaju Oluseyi Ifatimehin, Adams Ndalai Baba

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

Since 1991 when it became the capital city of Abia State, Umuahia has undergone tremendous transformation in its land use and land cover due to rapid urbanization. The main materials employed for this study are a land use map (1991) and Landsat ETM+satellite image (2007) of the study area. These, combined with field survey/checks, were brought into a GIS environment using ILWIS 3.2 Academic image classification software to map the land use/land cover and to estimate the rate of urban expansion and loss of rural land at the peri-urban fringes of Umuahia between 1991 and 2007. The study revealed significant …


Gender Participation In The Management Of Tricycle Transport For Youth Empowerment And Sustainable Development In Kano State, Nigeria, Nuratu Muhammed Jun 2011

Gender Participation In The Management Of Tricycle Transport For Youth Empowerment And Sustainable Development In Kano State, Nigeria, Nuratu Muhammed

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

The research examined gender participation in the management of tricycle for youth empowerment and sustainable development in Kano state, Nigeria. Stratified random sampling technique was used to select samples of drivers(150), passengers (150) and owners/managers the female tricycle owners fell under this category and they numbered(65).All together a total of 365 samples were selected for the study. Data obtained from the primary data was analyzed using simple statistical techniques and chi square test to ascertain whether there was any significant differences in some of the variables tested. The results of the analysis revealed that the main difference was found in …


Science Boot Camp For Librarians: Cpd On A Shoestring, Maxine G. Schmidt, Rebecca Reznik-Zellen May 2011

Science Boot Camp For Librarians: Cpd On A Shoestring, Maxine G. Schmidt, Rebecca Reznik-Zellen

Maxine G Schmidt

Science Boot Camp for Librarians was envisioned as a casual but intensive immersion event into selected scientific subjects that employ networked computing capabilities for research and collaboration. The goal of the event is to provide librarians with networking opportunities, but more importantly, to give them some of the context and ocabulary of a discipline to enable them to better engage faculty and research scientists with regard to escience. A half-day is devoted to each of three topics chosen for that year’s camp. A local faculty member provides an overview of the research area, and a second describes a single project …


Environmental Problems Of Industrialization And Sustainable Development In Nigeria - A Review, Adejoh Iyaji Feb 2011

Environmental Problems Of Industrialization And Sustainable Development In Nigeria - A Review, Adejoh Iyaji

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

The main objective of this paper is to examine the impact of the quest for industrialization on the environment in Nigeria; others include, the identification of the objectives of sustainable development as well as making recommendations that will lead to the much needed sustainable environment both for the present generation and generations yet unborn. The researcher relied principally on secondary sources of data for this paper which is theoretical in approach. Findings revealed the emergence of a host of environmental problems such as air pollution, deforestation, desertification, solid and hazardous waste problems in the wake of the quest for industrialization. …


Prevalence Of Piscine Myocarditis Virus (Pmcv) In Marine Fish Species, Torstein Tengs Dr. Jan 2011

Prevalence Of Piscine Myocarditis Virus (Pmcv) In Marine Fish Species, Torstein Tengs Dr.

Dr. Torstein Tengs

No abstract.


Optimal Control Of Switched Autonomous Systems In Microbial Fed-Batch Cultures, Chongyang Liu, Enmin Feng Jan 2011

Optimal Control Of Switched Autonomous Systems In Microbial Fed-Batch Cultures, Chongyang Liu, Enmin Feng

Chongyang Liu

A switched autonomous system is proposed to formulate the fed-batch culture process by taking the switching instants between the feed and batch processes as control variables. To maximize the concentration of 1,3-propanediol (1,3-PD) at the terminal time, an optimal control model subject to our proposed switched autonomous system and continuous state inequality constraints is then presented.Acomputational approach is developed to find the optimal switching instants in two aspects. On the one hand, the constraint transcription and smoothing techniques are applied to dealing with the continuous state inequality constraints; on the other hand, the first and the second derivatives of the …


The Domain Of Images, Chapter 1, In Portuguese, James Elkins Jan 2011

The Domain Of Images, Chapter 1, In Portuguese, James Elkins

James Elkins

This is the opening chapter of the book "Domain of Images" (Cornell University Press), in Portuguese.


The Stability Of The Extended Model Of Hypothalamic-Pituitary-Adrenal (Hpa) Axis Examined By Stoichiometric Network Analysis, Zeljko D. Cupic Jan 2011

The Stability Of The Extended Model Of Hypothalamic-Pituitary-Adrenal (Hpa) Axis Examined By Stoichiometric Network Analysis, Zeljko D. Cupic

Zeljko D Cupic

No abstract provided.


Predictive Modeling Of The Hypothalamic-Pituitary-Adrenal (Hpa) Axis Response To Acute And Chronic Stress, Zeljko D. Cupic Jan 2011

Predictive Modeling Of The Hypothalamic-Pituitary-Adrenal (Hpa) Axis Response To Acute And Chronic Stress, Zeljko D. Cupic

Zeljko D Cupic

No abstract provided.


The Survival Of The Conformist: Social Pressure And Renewable Resource Management, Alessandro Tavoni Jan 2011

The Survival Of The Conformist: Social Pressure And Renewable Resource Management, Alessandro Tavoni

Alessandro Tavoni

This paper examines the role of other-regarding behavior as a mechanism for the establishment and maintenance of cooperation in resource use under variable social and environmental conditions. By coupling resource stock dynamics with social dynamics concerning compliance to a social norm prescribing non-excessive resource extraction in a common 10 pool resource, we show that when reputational considerations matter and a sufficient level of social stigma affects the violators of a norm, sustainable outcomes are achieved. We find large parameter regions where norm-observing and norm-violating types coexist, and analyze to what extent such coexistence depends on the environment.


Creating A Soil Data Base In A Reconnaissance Soil Fertility Ssstudy Of An Encroached Forest Reserve In Northern Nigeria For A Reforestation Programme, F O. Adekayode, Dr. Dipo Theophilus Akomolafe Mbcs, Mncs, Mcpn, Jan 2011

Creating A Soil Data Base In A Reconnaissance Soil Fertility Ssstudy Of An Encroached Forest Reserve In Northern Nigeria For A Reforestation Programme, F O. Adekayode, Dr. Dipo Theophilus Akomolafe Mbcs, Mncs, Mcpn,

Dr. Dipo Theophilus Akomolafe MBCS, MNCS, MCPN,

The reconnaissance soil fertility study of 10,000 ha partly encroached forest reserve located between latitude 11°47’N and 11°56’N and longitude 4°22’E and 4°32’E in Northern Nigeria was conducted in 2009 to generate a soil fertility data base of the reserve. The tracking of the forest reserve boundary was done using a Garmin 72 model global positioning system (GPS) receiver. The geographic coordinates were input into the computer to generate a digital map of the forest reserve. The entire forest reserve was divided into grids to guide in the location for soil sampling using the GPS/Geographic Information System (GIS) geospatial technique. …


Metalurgia Extractiva Y Política Nacional, Fathi Habashi Jan 2011

Metalurgia Extractiva Y Política Nacional, Fathi Habashi

Fathi Habashi

Should a country export its mineral wealth in form of concentrates or should it locally treat its ores to produce metals as final products? In the past centuries pyrometallurgy was the only route to extract metals from ores and this required a large capital investment many countries could not afford to raise. This situation encouraged marketing of concentrates. Today, metallurgists have the option to use the hydrometallurgical route to process ores and concentrates at a reasonable capital investment. This opened the way to the possibility of processing ores locally. When need arises to increase production new units can be added …


Adaptive Responses To Flooding Incidents In Ilorin, Kwara State, Nigeria, Habiba I. Jimoh, Kayode A. Iroye Jan 2011

Adaptive Responses To Flooding Incidents In Ilorin, Kwara State, Nigeria, Habiba I. Jimoh, Kayode A. Iroye

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

Incidents of floods which are mainly caused by changes in landuse is fast becoming a city life experience in Ilorin as in most urban centres in Nigeria causing untold hardships and sometimes loss of lives. This extreme hydro-meteorological event is also being exacerbated by climate change which thus calls for adaptive response by residents towards reducing its risks, hence this study. Data used were generated from direct field measurements and questionnaire administration. Descriptive statistics and cross tabulations were used in analyzing the data. Results obtained indicate that most respondents use a wide range of non-structural adaptive response to flood. The …


An Assessment Of Socio-Economic Impact Of Waste Scavenging As A Means Of Poverty Alleviation In Gwagwalada, Abuja., John Yakubu Magaji, Samuel Panse Dakyes Jan 2011

An Assessment Of Socio-Economic Impact Of Waste Scavenging As A Means Of Poverty Alleviation In Gwagwalada, Abuja., John Yakubu Magaji, Samuel Panse Dakyes

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

Waste scavengers are usually perceived as being among the poor, and scavenging is considered a marginal activity. They tend to have low incomes, but can obtained decent earning when they are not exploited by middlemen. This study was conducted in Gwagwalada town with the aim of assessing the socio-economic impact of scavenging on the people. A structured questionnaire was constructed to capture the demographic characteristics of the scavengers, their experiences, types of items scavenged, the economic gains and the challenges being faced. The target pollution is waste scavengers and a random sampling technique was adopted in selecting the respondents for …


Generalized Benjamini-Hochberg Procedures Using Spacings, Debashis Ghosh Jan 2011

Generalized Benjamini-Hochberg Procedures Using Spacings, Debashis Ghosh

Debashis Ghosh

For the problem of multiple testing, the Benjamini-Hochberg (B-H) procedure has become a very popular method in applications. We show how the B-H procedure can be interpreted as a test based on the spacings corresponding to the p-value distributions. Using this equivalence, we develop a class of generalized B-H procedures that maintain control of the false discovery rate in finite-samples. We also consider the effect of correlation on the procedure; simulation studies are used to illustrate the methodology.


A Causal Framework For Surrogate Endpoints With Semi-Competing Risks Data, Debashis Ghosh Jan 2011

A Causal Framework For Surrogate Endpoints With Semi-Competing Risks Data, Debashis Ghosh

Debashis Ghosh

In this note, we address the problem of surrogacy using a causal modelling framework that differs substantially from the potential outcomes model that pervades the biostatistical literature. The framework comes from econometrics and conceptualizes direct effects of the surrogate endpoint on the true endpoint. While this framework can incorporate the so-called semi-competing risks data structure, we also derive a fundamental non-identifiability result. Relationships to existing causal modelling frameworks are also discussed.


Propensity Score Modelling In Observational Studies Using Dimension Reduction Methods, Debashis Ghosh Jan 2011

Propensity Score Modelling In Observational Studies Using Dimension Reduction Methods, Debashis Ghosh

Debashis Ghosh

Conditional independence assumptions are very important in causal inference modelling as well as in dimension reduction methodologies. These are two very strikingly different statistical literatures, and we study links between the two in this article. The concept of covariate sufficiency plays an important role, and we provide theoretical justication when dimension reduction and partial least squares methods will allow for valid causal inference to be performed. The methods are illustrated with application to a medical study and to simulated data.


A Primer Of Swarm Equilibria, Andrew J. Bernoff, Chad M. Topaz Jan 2011

A Primer Of Swarm Equilibria, Andrew J. Bernoff, Chad M. Topaz

Chad M. Topaz

We study equilibrium configurations of swarming biological organisms subject to exogenous and pairwise endogenous forces. Beginning with a discrete dynamical model, we derive a variational description of the corresponding continuum population density. Equilibrium solutions are extrema of an energy functional, and satisfy a Fredholm integral equation. We find conditions for the extrema to be local minimizers, global minimizers, and minimizers with respect to infinitesimal Lagrangian displacements of mass. In one spatial dimension, for a variety of exogenous forces, endogenous forces, and domain configurations, we find exact analytical expressions for the equilibria. These agree closely with numerical simulations of the underlying …


Niche Of Harmful Alga Aureococcus Anophagefferens Revealed Through Ecogenomics, Christopher Gobler, Dianna Berry, Sonya Dyhrman, Steven Wilhelm Jan 2011

Niche Of Harmful Alga Aureococcus Anophagefferens Revealed Through Ecogenomics, Christopher Gobler, Dianna Berry, Sonya Dyhrman, Steven Wilhelm

Steven Wilhelm

Harmful algal blooms (HABs) cause significant economic and ecological damage worldwide. Despite considerable efforts, a comprehensive understanding of the factors that promote these blooms has been lacking, because the biochemical pathways that facilitate their dominance relative to other phytoplankton within specific environments have not been identified. Here, biogeochemical measurements showed that the harmful alga Aureococcus anophagefferens outcompeted co-occurring phytoplankton in estuaries with elevated levels of dissolved organic matter and turbidity and low levels of dissolved inorganic nitrogen. We subsequently sequenced the genome of A. anophagefferens and compared its gene complement with those of six competing phytoplankton species identified through metaproteomics. …