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Revisiting The Economics Of Climate Change: The Role Of Geoengineering, Juan B. Moreno-Cruz, Sjak Smulders 2010 University of Calgary

Revisiting The Economics Of Climate Change: The Role Of Geoengineering, Juan B. Moreno-Cruz, Sjak Smulders

Juan B. Moreno-Cruz

Technically simple and reversible measures to directly reduce mean global temper- atures could be available anytime soon. We introduce the concept of \geoengineering" into an analytical model of climate change. We model the technical and economic characteristics of geoengineering in line with the recent literature from physical and environmental management sciences. We investigate (i) under which circumstances geoengineering can substitute, partly or completely, for traditional abatement strate- gies, (ii) under which conditions and at what level geoengineering is optimally em- ployed, and (iii) whether geoengineering can mitigate free-riding problems.


Mth 101/Fse 013 Tutorial, Morufu Oyedunsi Olayiwola 2010 Department of Mathematical Sciences,Olabisi Onabanjo University, Ago-Iwoye, Nigeria

Mth 101/Fse 013 Tutorial, Morufu Oyedunsi Olayiwola

OLAYIWOLA Morufu Oyedunsi

No abstract provided.


Meta-Analysis Of Fertilization Experiments Indicates Multiple Limiting Nutrients In Northeastern Deciduous Forests, Matthew A. Vadeboncoeur 2010 University of New Hampshire - Main Campus

Meta-Analysis Of Fertilization Experiments Indicates Multiple Limiting Nutrients In Northeastern Deciduous Forests, Matthew A. Vadeboncoeur

Matthew A Vadeboncoeur

It is widely accepted that N limits primary production in temperate forests, although colimitation by N and P has also been suggested, and on some soils, Ca and base cations are in short supply. I conducted a meta-analysis to assess the strength of existing experimental evidence for limitation of primary production by N, P, and Ca in hardwood forests of the northeastern United States and southeastern Canada using data from 35 fertilization experiments in deciduous forests on glaciated soils across the region.

There is strong evidence for N limitation (formal meta-analysis weighted mean response ratio = 1.51, p < 0.01; simple mean = 1.42, p < 0.001). Forest productivity also tended to increase with additions of P (simple mean = 1.15, p = 0.05) and Ca (simple mean = 1.36, p < 0.001). Across all treatments, 85% of response ratios were positive. Multiple-element additions had larger effects than single elements, but factorial experiments showed little evidence of synergistic effects between nutrient additions. Production responses correlated positively with the rate of N fertilization, but this effect was reduced at high rates of ambient N deposition.


Application Of Causal Inference Methods To Improve The Treatment Of Hiv In Resource-Limited Settings., Maya Petersen 2010 University of California, Berkeley

Application Of Causal Inference Methods To Improve The Treatment Of Hiv In Resource-Limited Settings., Maya Petersen

Maya Petersen

No abstract provided.


Simple Room-Temperature Preparation Of High-Yield Large-Area Graphene Oxide, Huang Nay Ming 2010 University of Malaya

Simple Room-Temperature Preparation Of High-Yield Large-Area Graphene Oxide, Huang Nay Ming

Huang Nay Ming

Graphene has attracted much attention from researchers due to its interesting mechanical, electrochemical, and electronic properties. It has many potential applications such as polymer filler, sensor, energy conversion, and energy storage devices. Graphene-based nanocomposites are under an intense spotlight amongst researchers. A large amount of graphene is required for preparation of such samples. Lately, graphene-based materials have been the target for fundamental life science investigations. Despite graphene being a much sought-after raw material, the drawbacks in the preparation of graphene are that it is a challenge amongst researchers to produce this material in a scalable quantity and that there is ...


Observations Of Ozone Production In A Dissipating Tropical Convective Cell During Tc4, Gary A. Morris, A. M. Thompson, K. E. Pickering, S. Chen, E. J. Bucsela, P. A. Kucera 2010 Valparaiso University

Observations Of Ozone Production In A Dissipating Tropical Convective Cell During Tc4, Gary A. Morris, A. M. Thompson, K. E. Pickering, S. Chen, E. J. Bucsela, P. A. Kucera

Gary A. Morris

From 13 July–9 August 2007, 25 ozonesondes were launched from Las Tablas, Panama as part of the Tropical Composition, Cloud, and Climate Coupling (TC4) mission. On 5 August, a strong convective cell formed in the Gulf of Panama. World Wide Lightning Location Network (WWLLN) data indicated 563 flashes (09:00–17:00 UTC) in the Gulf. NO2 data from the Ozone Monitoring Instrument (OMI) show enhancements, suggesting lightning production of NOx. At 15:05 UTC, an ozonesonde ascended into the southern edge of the now dissipating convective cell as it moved west across the Azuero Peninsula. The balloon oscillated ...


Enhancement Of Brønsted Acidity In Sulfate-Vanadium Treated Silica-Titania Aerogel As Oxidative-Acidic Bifunctional Catalyst, Siew Ling Lee, Soo Chien Wei, Hadi Nur, Halimaton Hamdan 2010 University Technology Malaysia

Enhancement Of Brønsted Acidity In Sulfate-Vanadium Treated Silica-Titania Aerogel As Oxidative-Acidic Bifunctional Catalyst, Siew Ling Lee, Soo Chien Wei, Hadi Nur, Halimaton Hamdan

Hadi Nur

Enhancement of Brønsted acidity in silica-titania aerogel was achieved by loading both sulfate and vanadium onto the material. This phenomena could be due to formation of V(OSi)2OH-O-SO3 in the resulted sample. In contrast, no noticeable Brønsted acidity was detected in vanadium loaded silica-titania aerogel (V/ST). UV-vis DR analysis results showed that the amount of hydrated tetrahedral titanium species, which acts as oxidative site, increased significantly upon sulfation and vanadium loading on the surface of the aerogel. However, presence of vanadium in the samples tended to transform framework tetrahedral titanium to extra framework octahedral titanium structure. The catalytic ...


Physicochemical Characteristics Of Phosphoric Acid Stabilized Bentonite, Amin Eisazadeh, Khairul Anuar Kassim, Hadi Hadi 2010 University Technology Malaysia

Physicochemical Characteristics Of Phosphoric Acid Stabilized Bentonite, Amin Eisazadeh, Khairul Anuar Kassim, Hadi Hadi

Hadi Nur

The expansive nature of soils containing high amounts of montmorillonite mineral can be altered through chemical stabilization, resulting in a material suitable for construction purposes. In this paper, the physicochemical behaviour of phosphoric acid treated samples was studied using X-ray Diffractometry (XRD), Energy Dispersive X-ray Spectrometry (EDAX), Field Emission Scanning Electron Microscopy (FESEM), Fourier Transform Infrared Spectroscopy (FTIR), and Solid-State Nuclear Magnetic Resonance spectroscopy (SS-NMR). It was found that in acid stabilized montmorillonitic soil, clay alumina was more susceptible to dissolution and mostly responsible for the formation of aluminate phosphate hydrate compounds that bonded the soil particles together. Furthermore, since ...


Friedel-Crafts Alkylation Of Resorcinol Over Mesoporous Alumina Loaded With Sulfuric Acid, Sheela Chandren, Zainab Ramli, Hadi Nur 2010 University Technology Malaysia

Friedel-Crafts Alkylation Of Resorcinol Over Mesoporous Alumina Loaded With Sulfuric Acid, Sheela Chandren, Zainab Ramli, Hadi Nur

Hadi Nur

Mesoporous alumina which contains only Lewis acidity was synthesized by sol-gel method and was then impregnated with sulfuric acid to generate Brönsted acidity. The catalyst was used in Friedel-Crafts alkylation of resorcinol with methyl tert-butyl ether to produce 4-tert-butylresorcinol and 4,6-di-tert-butylresor- cinol as the major and minor products respectively. It was demonstrated that Lewis and Brönsted acidities play a synergetic role in this reaction.


2-(3-Nitrophenoxy)Quinoxaline, Hairul Anuar Bin Tajuddin 2010 University of Malaya

2-(3-Nitrophenoxy)Quinoxaline, Hairul Anuar Bin Tajuddin

Hairul Anuar Bin Tajuddin

In the title molecule, C(14)H(9)N(3)O(3), the dihedral angle between the quinoxaline and benzene rings is 77.13 (9)degrees. The molecule is twisted about the ether-benzene O-C bond, with a C-O-C-C torsion angle of -102.8 (2)degrees. In the crystal, molecules are linked by C-H center dot center dot center dot O hydrogen bonds, forming layers in the ab plane, with one nitro O atom accepting two such interactions. The layers stack along the c-axis direction via weak C-H center dot center dot center dot pi interactions.


Sphet: Spatial Models With Heteroskedastic Innovations In R, Gianfranco Piras 2010 Regional Research Institute, West Virginia University

Sphet: Spatial Models With Heteroskedastic Innovations In R, Gianfranco Piras

Gianfranco Piras

No abstract provided.


Browse Biomass Removal And Nutritional Condition Of Moose Alces Alces, C Tom Seaton, Thomas F. Paragi, Rodney D. Boertje, Knut Kielland, Stephen DuBois, Craig L. Fleener 2010 University of Alaska, Fairbanks

Browse Biomass Removal And Nutritional Condition Of Moose Alces Alces, C Tom Seaton, Thomas F. Paragi, Rodney D. Boertje, Knut Kielland, Stephen Dubois, Craig L. Fleener

Craig L Fleener

No abstract provided.


An Analysis Of Temperature Variations Using Remote Sensing Approach In Lokoja Area, Fanan Ujoh Mr, Olarewaju O. Ifatimehin Mr, Sunday Ishaya Mr 2010 Benue State University

An Analysis Of Temperature Variations Using Remote Sensing Approach In Lokoja Area, Fanan Ujoh Mr, Olarewaju O. Ifatimehin Mr, Sunday Ishaya Mr

Dr. Fanan Ujoh

This study investigates the thermal variations of the different land use/cover types in urban Lokoja town retrieved from Landsat TM imagery of 1987. Band 2, 3, 4 and 6 of the imagery were used in the classification, estimation of NDVI, land surface emissivity values, and satellite sensor temperature. The Qin et al’s mono window algorithm was employed to obtain the land surface temperatures of the different land use/cover types classified. The results indicate that there is a significant variation in temperatures among the different land use/cover types in Lokoja. The built up area and the vacant ...


Aqua Science Through The Ages. An Illustrated History Of Water, Fathi Habashi 2010 Laval University, Quebec City, Canada

Aqua Science Through The Ages. An Illustrated History Of Water, Fathi Habashi

Fathi Habashi

Water a component of the Four Elements considered by the ancient philosophers as essential for survival, played, and is still playing an essential role in society. Great civilizations in ancient times developed along great rivers. The ancient peoples knew how to manage water supplies by digging canals, controlling floods, and using water for irrigation. They designed equipment that used water to measure the time, to determine the density of solids, to fight fires, and to create vacuum. Modern engineers exploited water flow to design and construct huge hydroelectric power stations. Waterways and navigation systems were also an essential element for ...


Discrete Nonparametric Algorithms For Outlier Detection With Genomic Data, Debashis Ghosh 2010 Penn State University

Discrete Nonparametric Algorithms For Outlier Detection With Genomic Data, Debashis Ghosh

Debashis Ghosh

In high-throughput studies involving genetic data such as from gene expression mi- croarrays, dierential expression analysis between two or more experimental conditions has been a very common analytical task. Much of the resulting literature on multiple comparisons has paid relatively little attention to the choice of test statistic. In this article, we focus on the issue of choice of test statistic based on a special pattern of dierential expression. The approach here is based on recasting multiple comparisons procedures for assessing outlying expression values. A major complication is that the resulting p-values are discrete; some theoretical properties of sequential testing ...


Detecting Outlier Genes From High-Dimensional Data: A Fuzzy Approach, Debashis Ghosh 2010 Penn State University

Detecting Outlier Genes From High-Dimensional Data: A Fuzzy Approach, Debashis Ghosh

Debashis Ghosh

A recent nding in cancer research has been the characterization of previously undis- covered chromosomal abnormalities in several types of solid tumors. This was found based on analyses of high-throughput data from gene expression microarrays and motivated the development of so-called `outlier' tests for dierential expression. One statistical issue was the potential discreteness of the test statistics. Using ideas from fuzzy set theory, we develop fuzzy outlier detection algorithms that have links to ideas in multiple comparisons. Two- and K-sample extensions are considered. The methodology is illustrated by application to two microarray studies.


Links Between Analysis Of Surrogate Endpoints And Endogeneity, Debashis Ghosh, Jeremy M. Taylor, Michael R. Elliott 2010 Penn State University

Links Between Analysis Of Surrogate Endpoints And Endogeneity, Debashis Ghosh, Jeremy M. Taylor, Michael R. Elliott

Debashis Ghosh

There has been substantive interest in the assessment of surrogate endpoints in medical research. These are measures which could potentially replace \true" endpoints in clinical trials and lead to studies that require less follow-up. Recent research in the area has focused on assessments using causal inference frameworks. Beginning with a simple model for associating the surrogate and true endpoints in the population, we approach the problem as one of endogenous covariates. An instrumental variables estimator and general two-stage algorithm is proposed. Existing surrogacy frameworks are then evaluated in the context of the model. A numerical example is used to illustrate ...


Meta-Analysis For Surrogacy: Accelerated Failure Time Models And Semicompeting Risks Modelling, Debashis Ghosh, Jeremy M. Taylor, Daniel J. Sargent 2010 Penn State University

Meta-Analysis For Surrogacy: Accelerated Failure Time Models And Semicompeting Risks Modelling, Debashis Ghosh, Jeremy M. Taylor, Daniel J. Sargent

Debashis Ghosh

There has been great recent interest in the medical and statistical literature in the assessment and validation of surrogate endpoints as proxies for clinical endpoints in medical studies. More recently, authors have focused on using meta-analytical methods for quanti cation of surrogacy. In this article, we extend existing procedures for analysis based on the accelerated failure time model to this setting. An advantage of this approach relative to proportional hazards model is that it allows for analysis in the semi-competing risks setting, where we constrain the surrogate endpoint to occur before the true endpoint. A novel principal components procedure is ...


Spline-Based Models For Predictiveness Curves, Debashis Ghosh, Michael Sabel 2010 Penn State University

Spline-Based Models For Predictiveness Curves, Debashis Ghosh, Michael Sabel

Debashis Ghosh

A biomarker is dened to be a biological characteristic that is objectively measured and evaluated as an indicator of normal biologic processes, pathogenic processes, or pharmacologic responses to a therapeutic intervention. The use of biomarkers in cancer has been advocated for a variety of purposes, which include use as surrogate endpoints, early detection of disease, proxies for environmental exposure and risk prediction. We deal with the latter issue in this paper. Several authors have proposed use of the predictiveness curve for assessing the capacity of a biomarker for risk prediction. For most situations, it is reasonable to assume monotonicity of ...


Combining Multiple Models With Survival Data: The Phase Algorithm, Debashis Ghosh, Zheng Yuan 2010 Penn State University

Combining Multiple Models With Survival Data: The Phase Algorithm, Debashis Ghosh, Zheng Yuan

Debashis Ghosh

In many scientic studies, one common goal is to develop good prediction rules based on a set of available measurements. This paper proposes a model averaging methodology using proportional hazards regression models to construct new estimators of predicted survival probabilities. A screening step based on an adaptive searching algorithm is used to handle large numbers of covariates. The nite-sample properties of the proposed methodology is assessed using simulation studies. Application of the method to a cancer biomarker study is also given.


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