bluuebunny/crossref_metadata_2025 huggingface dataset:
Properties of Concrete Incorporating Magnetized Water
Authors: Abdel-Raouf Mohamed , Abou-Zeid Mohamed Nagib
Published: December 2009

Mixing water plays a major role in determining concrete workability, strength, and durability. Previous work has indicated that magnetizing the mixing water can introduce some improvements in concrete workability and strength when the level of magnetization is well adjusted. However, there is a scarcity of data on the impact of water magnetization on concrete properties, particularly its durability and long-term properties. There are no data available either on the impact on concrete performance of storage of magnetized water before mixing. In this work, concrete mixtures were made with water-to-cementitious material ratios of 0.35 and 0.45 with and without admixtures. Water was incorporated at levels of magnetization of 0, 0.1, 0.2, 0.3, and 0.4 tesla. A set of concrete mixtures was made with freshly magnetized water, and another set of mixtures was made with magnetized water that was left in storage for 3 days. Testing included unit weight, air content, slump, slump retention, compressive strength, modulus of rupture, water permeability, rapid chloride permeability, chemical soundness, and abrasion resistance. Results reveal that magnetized water enhances concrete workability although the enhancement varies according to mix parameters. Some indications of improvements in concrete durability were also observed. Yet reduction in concrete mechanical properties was recorded in several mixtures. Care should be taken in selecting the magnetic field to ensure minimal negative impacts. A detailed assessment is needed to evaluate the feasibility of magnetized-water concrete, which may have merit, particularly for concrete mixing plants.
Effect of Relative Humidity on Coefficient of Thermal Expansion of Hardened Cement Paste and Concrete
Authors: Yeon Jung Heum , Choi Seongcheol , Won Moon C.
Published: December 2009

The coefficient of thermal expansion (CTE) of concrete has substantial effects on the behavior and performance of portland cement concrete (PCC) pavement. The CTE is one of the input variables with significant effects on PCC pavement performance in the newly developed Mechanistic–Empirical Pavement Design Guide. Currently, the most advanced and accepted evaluation method for the CTE is the provisional AASHTO TP60. In this test method, concrete specimens are saturated before and during the testing. It has been recognized that the CTE of cement paste is influenced by the relative humidity (RH) within the specimen. Results from previous research studies were nearly consistent: the maximum CTE value occurs at about 70% RH and its value is almost twice the value at 100% RH. Laboratory evaluations were conducted to quantify the effects of RH on CTEs in cement paste and concrete. In the testing program, target RH levels within the specimens were 45%, 60%, 70%, 80%, and 100%. RH sensors were installed within the specimens during their preparation. The specimens were fabricated and cured in 23°C (73°F) and 50% RH conditions for 6 weeks. Subsequently, the specimens were placed in the environmental chamber until the internal RH values reached the target RH levels. Then CTE testing was conducted by changing temperatures while evaluating displacements with externally mounted vibrating wire gauges. The results showed some effects of RH on the CTE of cement paste and concrete, with maximum values at about 70% to 80% RH. The effect was larger for cement paste than for concrete. Considering the small effects of RH on the concrete CTE, AASHTO TP60 appears to provide adequate CTE values for PCC pavement analysis for environmental stresses.
Evaluation of D-Cracking Preventive Measures in Ohio Test Pavement
Authors: Dryden John B. , Chapin L. Travis
Published: December 2009

A test pavement located on part of State Route 2 near Vermilion, Ohio, was built in 1975 with sections designed to investigate the role of pavement design and material variables that included aggregate source and size, subbase drainage systems, pavement joint design, subbase materials, joint sealants, cement, type of cure, and joint spacing on D-cracking. In 1998 the current study was initiated to understand better the concrete durability of the different composition variables of the pavement sections after 23 years of performance. The study established a methodology to analyze the pavement sections, gathered data, and analyzed the data with SAS statistical software. Significant findings on the variables affecting the performance of pavement sections were obtained. Key findings show the impact of aggregate source and size, joint sealants, and vapor barriers on pavement D-cracking performance and overall pavement performance. On the basis of the findings from this research, the requirement to use larger-size aggregate in concrete pavement was incorporated into the Ohio Department of Transportation (ODOT) 2002 Construction and Material Specifications. Also, the 2009 ODOT specifications will eliminate the requirement for joint sealing in new concrete pavement in part because of the findings of this study.
Performance of Rigid Pavements Containing Recycled Concrete Aggregate
Authors: Gress David L. , Snyder Mark B. , Sturtevant Jeffrey R.
Published: December 2009

A 1994 field survey was undertaken of pavements containing recycled concrete aggregate (RCA) constructed in Connecticut, Kansas, Minnesota, Wisconsin, and Wyoming. These pavements were resurveyed during the summer of 2006 to update their performance after they had been subjected to 12 more years of traffic. Additional pavements made with RCA from Illinois and Iowa were also observed in 2006. Although the recycled pavements contain higher mortar contents, there was no clear correlation between the higher total mortar content of RCA concrete pavements and cracking distresses in either survey, although one RCA concrete pavement did exhibit more cracking than the control pavement. Overall there was little difference between the 1994 and 2006 surveys. Several pavements were rehabilitated by the addition of dowels for load transfer. These pavements are performing exceptionally well and show that rehabilitation techniques normally applied to conventional concrete work effectively on recycled pavements. Laboratory evaluation of field cores showed that 10 of the 16 pavements surveyed exhibited evidence of alkali–silica reactivity. Eight of these pavements were shown to have significant remaining expansion potential and are expected to continue expanding. All pavements constructed with RCA from concrete showing alkali–silica reactivity and D-cracking exhibited field performance equivalent to their controls and pavements without distress. The recycled pavements have generally performed comparably with their controls. For instance, the present serviceability rating was found to be similar for the recycled and control sections.
Effect of Clinker Chemistry on Salt Scaling Resistance of Concrete
Authors: Taylor Peter C.
Published: December 2009

Work was conducted under a larger experimental program investigating the effects of processing additions on the performance of portland cements in concrete mixtures. One of the findings of this work is that there appears to be a trend that increasing tricalcium aluminate and the alkali content of the cement clinker increases the risk of freeze–thaw damage when tests are done in the laboratory. This trend was observed in mixtures with adequate air void systems and similar compressive strengths. It is possible that this effect is due to the increased osmotic pressures set up by increasing alkali contents in the pore solutions.
Sustainable Concrete through Reuse of Crushed Returned Concrete
Authors: Obla Karthik H. , Kim Haejin
Published: December 2009

Every year an estimated 2% to 10% (average of 5%) of the estimated 455 million yd3 of ready-mixed concrete produced in the United States (2006 estimate) is returned to the concrete plant. The returned concrete can be handled in several different ways. A common approach is to discharge the returned concrete in the concrete plant and crush the hardened concrete. The coarser material can be reused as base for pavements or fill for other construction. However, it is not easy to utilize the material finer than 2 in. A research project was undertaken by the National Ready Mixed Concrete Association Research Laboratory to study the use of crushed returned concrete, referred to as crushed concrete aggregate (CCA), as a portion of the aggregate component in new concrete. Demolishing old concrete structures, crushing the concrete, and using the crushed materials as aggregates, referred to as recycled concrete aggregate (RCA), have been researched to some extent. RCA is different from CCA because construction debris tends to have a high level of contamination (rebar, deicing salts, etc.). CCA, however, is prepared from concrete that has never been in service and thus is likely to contain much lower levels of contamination. The main objective of the research project was to develop technical data and provide guidance on a methodology for appropriate use of the material. Such a step can help the ready-mixed concrete industry achieve lower operating costs, reduce substantial landfill space, and support sustainable development.
Numerical Simulations of Fracture Resistance of Functionally Graded Concrete Materials
Authors: Evangelista Francisco , Roesler Jeffery , Paulino Glaucio
Published: December 2009

The concept of grading material composition in a predetermined direction to target multiple objectives and functionality is applicable to the layering and positioning of different materials at specified depths. From a fracture mechanics perspective, this study explores the advantages of using functionally graded concrete materials (FGCMs), that is, plain concrete and fiber-reinforced concrete (FRC), in two distinct layers. The fracture energy ( G) and residual load capacity ( Ps) of two-layered concrete beams are investigated by means of numerical simulations with a cohesive zone model (CZM) implemented in a finite element framework. The required fracture parameters for defining the CZM are obtained from individual fracture tests of the plain concrete and FRC materials. The numerical simulations analyzed the effects of FRC thickness and position (whether at the top or bottom of the beam) on the fracture resistance of the two-layered concrete beam. A cost–benefit analysis showed that the FRC placed in the bottom lift is more fracture efficient (higher G- and Pδ-values at lower cost) than when it is placed in the top lift. There is also an optimal FRC thickness in which the benefit in fracture resistance is reduced as the FRC layer is increased. The application of a CZM to predict the fracture behavior of an FGCM beam has demonstrated its potential for also quantifying the effects of FGCMs on the fracture resistance of concrete pavements.
Field and Laboratory Evaluation of Pervious Concrete Pavements
Authors: Delatte Norbert , Mrkajic Aleksandar , Miller Daniel I.
Published: December 2009

Portland cement pervious concrete (PCPC) is a material of increasing interest for parking lots and other applications. PCPC typically consists of coarse aggregates, portland cement, water, and various admixtures. Similar materials are used for cement-stabilized drainage layers in highway and airport pavements. In this research, in-service PCPC pavements were inspected in the field, and cores were removed in order to investigate properties in the laboratory. Field evaluation methods included visual inspection, two surface drainage measurements, and an indirect-transmission ultrasonic pulse velocity (UPV) test. Laboratory testing methods included void ratio, unit weight, compressive strength, splitting tensile strength, hydraulic conductivity, and direct-transmission UPV. Because it is compacted on the surface with screeds or rollers, PCPC generally has higher strength, lower void ratio, and lower permeability at the surface than at the bottom. Therefore, the properties of the tops and bottoms of core samples were compared. Generally, the PCPC installations evaluated under this research project have performed well in freeze–thaw environments with little maintenance required. No visual indicators of freeze–thaw damage were observed. With the exception of some installations in which the pore structure was sealed during construction with wet mixtures or overcompaction, nearly all sites showed fair to good infiltration capability on the basis of drain-time measurements.
Determining Rapid-Setting Material Suitability for Expedient Pavement Repairs
Authors: Priddy Lucy P. , Jersey Sarah R. , Freeman Reed B.
Published: December 2009

Numerous commercial off-the-shelf products have become available for small surface repairs in portland cement concrete (PCC) pavements, providing short set times, high early strengths, and good durability to withstand heavy loads. These materials have been used successfully for both small repairs in the transportation industry and industrial applications in which the repair was less than 0.03 m3 (1 ft3). Applying these products for larger-volume repairs while still achieving a traffickable surface within 3 h of pavement repair has been a challenge. Experience gained from testing these products for full-depth repairs provides guidance for repair techniques that will expedite opening airfield or highway pavements to traffic and minimize the frequency of maintenance activities. An investigation conducted at the U.S. Army Engineer Research and Development Center, in Vicksburg, Mississippi, examined nine rapid-setting materials for repair of PCC pavements through laboratory characterization and full-scale traffic tests. Standard laboratory tests were performed to characterize the material properties over time and to provide a mechanism for assessing the material suitability for field repairs. Repairs with approximate volumes of 0.7 m3 (1.5 yd3) were constructed and evaluated under controlled traffic conditions to determine the ability of the repairs to support 100 simulated passes of an F-15E aircraft within 3 h of repair. Results of traffic tests identified seven repair materials that met these criteria. A laboratory protocol for selection of rapid-setting materials was developed based on the laboratory and full-scale test results. Use of the protocol will help prevent the selection of materials that are unlikely to meet performance expectations.
Reappraisal of Recycled Concrete Aggregate as Coarse Aggregate in Concretes for Rigid Pavements
Authors: Vancura Mary , Khazanovich Lev , Tompkins Derek
Published: December 2009

State departments of transportation began using recycled concrete aggregate (RCA) as aggregate in portland cement concrete pavement in the United States in the late 1970s. Although RCA is rarely used in current U.S. rigid pavement slabs, the impetus for its continued use remains the same: a lack of landfill space, a shortage of nearby quality natural aggregates, or both. However, as American pavement engineers and researchers place a greater emphasis on sustainable, reusable roadways, the status quo for RCA in American roadways should be reconsidered along with these new priorities. This study proposes to revisit the use of recycled concrete as aggregate in rigid pavement slabs by using overlooked research to address the concerns that prevented the wide-scale adoption of recycled concrete as an aggregate in pavement slabs by state departments of transportation. Experiences encountered in countries (mostly restricted to Europe) where the use of RCA in rigid pavement is more common are also described. New opportunities for the use of RCA as a structural component in pavement concretes are detailed.
Road Crash History and Risk Groups in India
Authors: Ponnaluri Raj V. , Santhi Y. Durga
Published: December 2009

Historically, India has never before experienced the type of vehicular growth as that of the past decade. The number of registered vehicles in the nation increased from 30.29 million in 1995 to 66.29 million in 2005, while road crashes, persons injured, and traffic fatalities increased by 82%, 68%, and 44%, respectively. This paper presents a quantitative perspective on road crashes in India and identifies risk categories. Three levels of analysis were completed: ( a) a nationwide crash assessment for 2001 and 2005, ( b) a crash evaluation for a group of 35 urban agglomerations (UAs), and ( c) modal comparisons to identify risk groups. Data analysis for UAs showed that the primary risk categories were for motorized two-wheelers, pedestrians, and bicyclists, who had a share of 27%, 20%, and 5% of fatalities, respectively. Outside of UAs, heavy vehicles posed the highest risk, with a 23% share of nationwide fatalities. While the country's draft national road safety policy broadly speaks to initiatives such as raising safety awareness and ensuring safe road infrastructure, the ground-level conditions are different. This paper discusses the problems faced by the road user and calls for immediate action to ( a) develop a road accident reporting system and a national access management policy, ( b) enforce traffic rules rigorously, ( c) ensure compliance with vehicle maintenance rules, ( d) modify driver behavior, and ( e) commit to design and construction of good road infrastructure with safety as a priority. In this context, initiatives to build projects in a public–private partnership mode are a welcome change, as they can better integrate road design and traffic safety issues.
Financial Model to Assess Value Capture Potential of a Roadway Project
Authors: Vadali Sharada R. , Aldrete Rafael M. , Bujanda Arturo
Published: December 2009

Value capture refers to the process by which all or a portion of increments in land value attributed to community efforts rather than to landowner actions are recovered by the public sector. As such, it is a form of a public–private partnership. It is widely used across the country and around the world for transit applications; however, its applications to roadways have only recently emerged into discussions of roadway finance, out of motivation stemming from the transportation funding crisis. Two states have legislative provisions for enabling value capture for financing transportation. In Texas, this takes the form of a transportation reinvestment zone (TRZ). This paper presents specifications for a TRZ based on a case study approach and then applies a financial evaluation model based on those specifications to a case study corridor in El Paso, Texas, to assess preliminary revenue sources and cash flows that can be accrued for value capture bonding capacity.
Private Funding of Intermodal Exchange Stations in Urban Areas
Authors: Di Ciommo Floridea , Vassallo José Manuel , Oliver Arturo
Published: December 2009

Many municipal governments are seeking ways to promote the use of public transportation in urban areas through investments in new infrastructure. However, budgetary constraints are often an important obstacle to these undertakings. This paper describes the case in Madrid, Spain, of funding intermodal exchange stations with private capital through the concession approach. It is possible to fund urban transport infrastructure in such a way that private profit and social benefit converge. This paper shows that the construction of intermodal exchange stations in Madrid yields important social benefits to all the stakeholders: commuters save travel time, bus companies diminish their costs of operation, abutters gain in quality of life, and society benefits from a reduction of emissions. Simultaneously, the government is able to promote these infrastructure facilities without spending more of scarce budgetary resources. In recognition of these advantages, this paper makes some suggestions for improving upon the present approach.
Value for Money Analysis in U.S. Transportation Public–Private Partnerships
Authors: Morallos Dorothy , Amekudzi Adjo , Ross Catherine , Meyer Michael
Published: December 2009

Value for money (VfM) assessment has been used by various public agencies worldwide as a tool to compare the viability of pursuing a project as a public–private partnership (PPP) with traditional procurement. Although sources have described the use of VfM in Europe, Australia, and parts of Asia, relatively little is known of the use of such tools in the United States. This paper presents the results of a survey of state transportation agency officials on their PPP practices and their use of assessments and tools to evaluate public–private partnerships. From the evaluation, the paper provides a guided reference for public agencies looking to adopt the VfM methodology in their current PPP decision-making framework. It also provides recommendations for future adaptations to enhance the VfM tool's level of effectiveness.
Revenues from a Statewide Congestion Pricing Program
Authors: DeCorla-Souza Patrick , Luskin David
Published: December 2009

Many states in the United States have identified the need to invest in major highway corridors to accommodate growth and ensure the state's economy is competitive. With conventional pay-as-you-go approaches to funding and procurement, the necessary projects could take decades to complete and would require additional public funding. One innovative financing alternative that may be used in up to 15 states under the Federal Value Pricing Pilot Program is to employ congestion pricing to generate a revenue stream that can leverage the up-front private capital and thus accelerate the delivery schedule for planned state projects. With variable pricing, tolls on existing limited-access highways could be used to manage growing congestion. Revenues from the tolls could be used to ( a) pay for the expansion, reconstruction, or rehabilitation of some or all of these highways; ( b) help pay for the construction of new highways; and ( c) fund improvements in transit services the demand for which would be stimulated by road congestion pricing. This paper presents a sketch-planning approach to estimate the revenue that could be raised if a state were to implement congestion pricing on some or all of its freeways and, for illustrative purposes, demonstrates this approach with data for a case study state.
Developing a Value-Pricing Project
Authors: Macias Roberto , Poe Christopher , Ungemah David , MacGregor Matthew
Published: December 2009

Limited space to build new roads, fiscal constraints of federal and state government investment to fund new road construction or add capacity to the existing road infrastructure, and the need to use roads more efficiently have triggered in recent years a trend of looking for alternative ways to address the country's transportation needs. One alternative that has become increasingly accepted by politicians, decision makers, and the public is value pricing. This paper describes the current state of the Dallas, Texas, I-30W value-pricing project. This paper also describes the metrics developed at the beginning of the project to answer key questions related to the implementation of value pricing on I-30W. It presents the findings to date and provides guidance to other transportation agencies on methods to deploy a value-pricing project. Preliminary results for the survey and focus groups about managed lanes and value pricing are presented. The project found that a successful value-pricing project should include early definition of goals, early data collection for performance monitoring, and early development of public outreach.
Road Pricing as an Impetus for Environment-Friendly Travel Behavior
Authors: Janssens Davy , Cools Mario , Moons Elke , Wets Geert , Arentze Theo A. , Timmermans Harry J. P.
Published: December 2009

An important policy instrument for governments to modify travel behavior and manage the increasing travel demand is the introduction of a congestion pricing system. In this study, the influence of a detailed classification of activities is examined to assess likely traveler response to congestion pricing scenarios. Despite the fact that most studies do not differentiate between activity categories, the value of time and in general the space–time properties and constraints of different types of activities vary widely. For this reason, it is of importance to provide sufficient detail and sensitivity in assessing the impact of congestion pricing scenarios. In addition, a first assessment of travelers’ possible multifaceted adaptation patterns is presented. For these purposes, a stated adaptation study was conducted in Flanders, the Dutch-speaking region of Belgium. The experiment was conducted through an interactive stated adaptation survey. In the stated adaptation experiment, respondents could indicate their responses to the congestion pricing scenario. The most prevalent conclusion is that the activity type significantly predetermines the willingness to express a more environment-friendly behavior (i.e., reducing the number of trips, reducing the total distance traveled, switching to more environment-friendly modes). Also, the willingness to show ecological activity-travel behavior (e.g., carpooling and using public transport) in a nonpricing situation is a major differentiator of future behavior in a congestion pricing scenario.
Impact of Incentives on Toll Road Use by Trucks
Authors: Zhou Lin , Burris Mark W. , Baker Richard T. , Geiselbrecht Tina
Published: December 2009

In this research, interviews and survey data were used to understand better the truckers’ use of toll roads. On the basis of interviews with industry representatives, shipping companies, and drivers, it was clear that owner–operators were the least likely to use toll roads because of the difficulty in passing the cost of the toll on to their customers. Company-owned shipping operations were the most likely to analyze the potential benefits of a toll route carefully and possibly to use that route. A survey of truck drivers in the Austin, Texas, area was conducted both online and by paper. The survey's focus was on the use of State Highway (SH) 130, a tolled bypass route around Austin, versus the use of I-35, which runs through Austin. More than 2,000 respondents indicated their preferred route and whether certain incentives would motivate them to use SH-130. The survey results mirrored the results from the interviews, with smaller companies (owner–operators) preferring the nontoll route. The incentives that most interested the truckers were off-peak discounts, followed by the incentive of a free trip after a number of paid trips. The average value of travel time savings was $44.20/h.
Evaluating Estimation Techniques of Transportation Price Elasticity
Authors: Han Chien-Pai , Li Jianling
Published: December 2009

Price elasticity is critical for managed lane planning. To set an effective pricing policy that can achieve a specific objective–-whether it is to maximize freeway system performance, to reduce vehicle emission, or to capitalize on revenue–-transportation planners and policy makers need to know how users would react to various pricing policies. The issue is even more important when the public has not yet fully embraced transportation pricing. Three techniques have been frequently used for estimating transportation price elasticities: shrinkage ratio, midpoint elasticity, and log arc elasticity. However, little is known about the suitability of the techniques. This paper evaluates these techniques by analyzing their statistical properties and comparing their relative efficiency. The findings suggest that the appropriateness of an estimation technique of price elasticity varies from one circumstance to another. It is important to understand the variations and apply the techniques accordingly.
Zinc-specific Food Frequency QuestionnaireTo Assess College Women’s Eating Habits
Authors: Lacey Janet M. , Zotter Deanne U.
Published: December 2009

Zinc deficiency has been reported in individuals with eating disorders, the risks of which increase during the adolescent and early adult years. A food frequency questionnaire (FFQ) specific for zinc-rich foods was tested for its usefulness in identifying problematic eating behaviour tendencies in college-age women. Ninety-two female students enrolled in a university introductory psychology course volunteered to complete demographic information, the Eating Attitudes Test (EAT-26), and a zinc-specific FFQ (ZnFFQ). Relationships among estimated zinc intakes, food/lifestyle habits, and eating attitude variables were examined. Twenty-five women had estimated intakes below the Recommended Dietary Allowance (RDA) for zinc. Individuals in the highest zinc intake group (over twice the RDA) had a tendency to score higher on the EAT-26 and the bulimia subscale. Vegetarians also scored high on the EAT-26. Although our data are limited, the ZnFFQ should be studied further to determine whether it could play a useful role in identifying individuals at risk for bulimia. The ZnFFQ is a simple, non-confrontational assessment tool and may be a helpful starting point for identifying women with unhealthy eating habits.
Application of Fluorescence Techniques to Characterise the Preparation of Protein-Containing Sol-Gel Derived Hosts for use as Catalytic Media
Authors: Hungerford Graham , Rei Ana , Ferreira M. Isabel , Allison Archie , Mcloskey David
Published: December 2009

In this work we collate and review the usage that we have made of fluorescence techniques employed to follow the sol to gel transition and aging in different tetraethylorthosilicate based materials. The sol-gel method allows porous glasslike of good optical quality to be produced at relatively low (ambient) temperatures, which facilitates the incorporation of a range of molecules; from laser dyes to biomolecules. Here the use of “common” viscosity (DASPMI) and polarity (Nile red) sensitive fluorescence probes to monitor the host manufacture is made. Nile red was also used to label two catalytically active proteins (cytochrome c and subtilisin Carlsberg). These were incorporated into the different host media and the dye used to ascertain changes in protein conformation, both upon incorporation and at the end of an aging period. Complementary measurements of catalytic activity were performed. The probe emission was monitored via steady state and time-resolved fluorescence techniques and comparison made with the catalytic activity measurements to elucidate the amount of accessible and active protein. Overall it was found that the hosts became stable after an aging period approaching 20 days and that the major influence on the catalytic reaction rates was that of host mediated mass transport.
Becoming a proficient academic writer: shifting lexical preferences in the use of the progressive
Authors: Wulff Stefanie , Römer Ute
Published: December 2009

Recent corpus studies have shown that learners of English are aware of systematic associations between verbs and their preferred argument structures to an extent that is similar to that of a native speaker of English (e.g., Gries and Wulff, 2005 ). Given evidence for similarly systematic associations in native speaker data at the lexis–morphology interface (e.g., Römer, 2005a ), the question arises whether, and to what extent, learners of English are also sensitive to lexical dependencies at the level of morphology, and how their verb-aspect associations compare with those of native speakers.

In order to address this question, this study focusses on the potential associations between verbs and progressive aspect in German learners' academic writing. On the basis of the German component of the International Corpus of Learner English and the Cologne–Hanover Advanced Learner Corpus, learners' significantly preferred verb-aspect pairs are identified using an adaptation of collostructional analysis ( Stefanowitsch and Gries, 2003 ). The results are complemented with corresponding analyses of a subset of the Michigan Corpus of Upper-level Student Papers on the one hand and published research articles from the Hyland Corpus on the other hand.

The findings indicate that upper-intermediate and advanced German learners of English exhibit clear lexical preferences in the use of progressives. Furthermore, comparative analyses suggest that verb-aspect preferences shift as a function of writers' mastery of text type-specific conventions rather than language proficiency at large.
Image Similarity to Improve the Classification of Breast Cancer Images
Authors: Tahmoush Dave
Published: December 2009

Techniques in image similarity can be used to improve the classification of breast cancer images. Breast cancer images in the mammogram modality have an abundance of non-cancerous structures that are similar to cancer, which make classification of images as containing cancer especially difficult to work with. Only the cancerous part of the image is relevant, so the techniques must learn to recognize cancer in noisy mammograms and extract features from that cancer to appropriately classify images. There are also many types or classes of cancer with different characteristics over which the system must work. Mammograms come in sets of four, two images of each breast, which enables comparison of the left and right breast images to help determine relevant features and remove irrelevant features. In this work, image feature clustering is done to reduce the noise and the feature space, and the results are used in a distance function that uses a learned threshold in order to produce a classification. The threshold parameter of the distance function is learned simultaneously with the underlying clustering and then integrated to produce an agglomeration that is relevant to the images. This technique can diagnose breast cancer more accurately than commercial systems and other published results.
Calculation of Entropy for a Sinusoid with Beta-Distributed Phase
Authors: Michalowicz Joseph  V. , Olson Colin  C. , Bucholtz Frank , Nichols Jonathan  M.
Published: December 2009

In this paper, an analytical expression is developed for the differential entropy of a sinusoid with a Beta-distributed phase angle. This particular signal model is prevalent in optical communications, however an expression for the associated differential entropy does not currently exist. The expression we derive is approximate as it relies on a series expansion for one of the key terms needed in the derivation. However, we are able to show that the approximation is accurate (error ≤ 5%) for a wide variety of Beta parameter choices.
Pairwise Comparison Dynamics and Evolutionary Foundations for Nash Equilibrium
Authors: Sandholm William H.
Published: December 2009

We introduce a class of evolutionary game dynamics — pairwise comparison dynamics — under which revising agents choose a candidate strategy at random, switching to it with positive probability if and only if its payoff is higher than the agent’s current strategy. We prove that all such dynamics satisfy Nash stationarity: the set of rest points of these dynamics is always identical to the set of Nash equilibria of the underlying game. We also show how one can modify the replicator dynamic and other imitative dynamics to ensure Nash stationarity without increasing the informational demands placed on the agents. These results provide an interpretation of Nash equilibrium that relies on large numbers arguments and weak requirements on payoff observations rather than on strong equilibrium knowledge assumptions.
Natural Environment Suitability of China and Its Relationship with Population Distributions
Authors: Yang Xiaohuan , Ma Hanqing
Published: December 2009

The natural environment factor is one of the main indexes for evaluating human habitats, sustained economic growth and ecological health status. Based on Geographic Information System (GIS) technology and an analytic hierarchy process method, this article presents the construction of the Natural Environment Suitability Index (NESI) model of China by using natural environment data including climate, hydrology, surface configuration and ecological conditions. The NESI value is calculated in grids of 1 km by 1 km through ArcGIS. The spatial regularity of NESI is analyzed according to its spatial distribution and proportional structure. The relationship of NESI with population distribution and economic growth is also discussed by analyzing NESI results with population distribution data and GDP data in 1 km by 1 km grids. The study shows that: (1) the value of NESI is higher in the East and lower in the West in China; The best natural environment area is the Yangtze River Delta region and the worst are the northwest of Tibet and southwest of Xinjiang. (2) There is a close correlation among natural environment, population distribution and economic growth; the best natural environment area, the Yangtze River Delta region, is also the region with higher population density and richer economy. The worst natural environment areas, Northwest and Tibetan Plateau, are also regions with lower population density and poorer economies.
A Review of Computational Methods in Materials Science: Examples from Shock-Wave and Polymer Physics
Authors: Steinhauser Martin  O. , Hiermaier Stefan
Published: December 2009

This review discusses several computational methods used on different length and time scales for the simulation of material behavior. First, the importance of physical modeling and its relation to computer simulation on multiscales is discussed. Then, computational methods used on different scales are shortly reviewed, before we focus on the molecular dynamics (MD) method. Here we survey in a tutorial-like fashion some key issues including several MD optimization techniques. Thereafter, computational examples for the capabilities of numerical simulations in materials research are discussed. We focus on recent results of shock wave simulations of a solid which are based on two different modeling approaches and we discuss their respective assets and drawbacks with a view to their application on multiscales. Then, the prospects of computer simulations on the molecular length scale using coarse-grained MD methods are covered by means of examples pertaining to complex topological polymer structures including star-polymers, biomacromolecules such as polyelectrolytes and polymers with intrinsic stiffness. This review ends by highlighting new emerging interdisciplinary applications of computational methods in the field of medical engineering where the application of concepts of polymer physics and of shock waves to biological systems holds a lot of promise for improving medical applications such as extracorporeal shock wave lithotripsy or tumor treatment.
Functionality, in Vitro Digestibility and Physicochemical Properties of Two Varieties of Defatted Foxtail Millet Protein Concentrates
Authors: Mohamed Tabita Kamara , Zhu Kexue , Issoufou Amadou , Fatmata Tarawalie , Zhou Huiming
Published: December 2009

Two varieties of foxtail millet protein concentrates (white and yellow) were characterized for in vitro trypsin digestibility, functional and physicochemical properties. Millet protein concentrate was easily digested by trypsin in vitro. Essential amino acids were above the amounts recommended by the Food Agricultural Organization/World Health Organization (FAO/WHO/UNU) for humans. Yellow millet protein concentrate (YMPC) possessed the highest differential scanning calorimetry result (peak temperature of 88.98 °C, delta H = 0.01 J/g), white millet protein concentrate (WMPC) had the lowest (peak temperature 84.06 °C, delta H = 0.10 J/g). The millet protein concentrates had molecular sizes around 14.4 and 97.4 kDa. They have U-shape solubility curves. Waterbinding capacity was in the range of 5.0 and 7.0 g/g, while oil absorption capacity ranged between 4.8 and 5.9 g/g. WMPC had higher bulk density (0.22 g/mL) and emulsifying capacity than YMPC and Soy Protein Concentrate (SPC). Foam capacity and foam stability ranged from 137 to 73 g/mL for WMPC, from 124 to 61 g/mL SPC and from 124 to 46 g/mL for YMPC. Millet protein concentrates are potential functional food ingredients.
Synthesis of 3-[(Z)-2-piperazin-1-yl-ethylimino]-1,3-dihydro indol-2-one as a novel Schiff base
Authors: K. Ramakrishna Reddy , N. Mahendra K.
Published: December 2009

Isatin (1H-indole-2,3-dione) was first obtained by Erdman and Laurent in 1841 as a product from the oxidation of indigo by nitric and chromic acids [1].[...]
Synthesis and Protonation Constants of an Amide-Based Chelating Cyclophane
Authors: Altamirano-Coronado Julio Cesar , Godoy-Alcántar Carolina , Medrano Felipe
Published: December 2009

Our research group have reported that, under high dilution conditions, condensation reactions between 4,4’-ethylenebis(2,6-morpholinedione), 1, and aromatic diamines gave a new series of tetraaza chelating cylophanes, which have amide and aromatic groups in the ring framework and pendant carboxymethyl groups [1].[...]
4,4’-Bis(4-octylphenoxy)-2,2’-bipyridine
Authors: Liu Ru , Xu Yan , Wang Jun-Ru , Du Zhen-Ting
Published: December 2009

4,4’-Bis(4-octylphenoxy)-2,2’-bipyridine which can be used in complexes of ruthenium was synthesized. This ligand bears a long chain for the purpose of increasing the solubility of the final complex. The synthesis was achieved through a nucleophilic aromatic substitution reaction of 4,4’-bromo-2,2’-bipyridine and 4-octylphenol.
Nanoporous Gold: Fabrication, Characterization, and Applications
Authors: Seker Erkin , Reed Michael  L. , Begley Matthew  R.
Published: December 2009

Nanoporous gold (np-Au) has intriguing material properties that offer potential benefits for many applications due to its high specific surface area, well-characterized thiol-gold surface chemistry, high electrical conductivity, and reduced stiffness. The research on np-Au has taken place on various fronts, including advanced microfabrication and characterization techniques to probe unusual nanoscale properties and applications spanning from fuel cells to electrochemical sensors. Here, we provide a review of the recent advances in np-Au research, with special emphasis on microfabrication and characterization techniques. We conclude the paper with a brief outline of challenges to overcome in the study of nanoporous metals.
Towards Commercial Production of Sponge Medicines
Authors: Koopmans Marieke , Martens Dirk , Wijffels Rene H.
Published: December 2009

Sponges can provide potential drugs against many major world-wide occurring diseases. Despite the high potential of sponge derived drugs no sustainable production method has been developed. Thus far it is not fully understood why, when, where and how these metabolites are produced in sponges. For the near future sea-based sponge culture seems to be the best production method. However, for controlled production in a defined system it is better to develop in vitro production methods, like in vitro sponge culture or even better sponge cell culture, culture methods for symbionts or the transfer of production routes into another host. We still have insufficient information about the background of metabolite production in sponges. Before production methods are developed we should first focus on factors that can induce metabolite production. This could be done in the natural habitat by studying the relation between stress factors (such as predation) and the production of bioactive metabolites. The location of production within the sponge should be identified in order to choose between sponge cell culture and symbiont culture. Alternatively the biosynthetic pathways could be introduced into hosts that can be cultured. For this the biosynthetic pathway of metabolite production should be unraveled, as well as the genes involved. This review discusses the current state of sponge metabolite production and the steps that need to be taken to develop commercial production techniques. The different possible production techniques are also discussed.
Phenolic Compound Profiles in Berry Skins from Nine Red Wine Grape Cultivars in Northwest China
Authors: Jin Zan-Min , He Jian-Jun , Bi He-Qiong , Cui Xiang-Yun , Duan Chang-Qing
Published: December 2009

Phenolic compound profiles were investigated by HPLC-MS in two consecutive years to assess genotypic variation in berry skins of nine red Vitis vinifera cultivars. The results showed that the types and levels of phenolic compounds greatly varied with cultivar. Common wine grape cultivars such as Syrah, Cabernet Sauvignon, Cabernet Gernischt and Merlot contained more types of anthocyanins, flavonols, flavan-3-ols, stilbenes and phenolic acids than Gamay, Yan73, Pinot Noir, Zinfandel and Мускат Розовый. Yan 73 and Pinot Noir had abundant anthocyanins, but only a few nonanthocyanin phenolic compounds. Gamay, Zinfandel and Мускат Розовый contained only a few anthocyanins and flavonols. For a grape cultivar, the ratio of one anthocyanin content to total anthocyanin content did not change greatly from one year to the next, unlike for non-anthocyanins. Cluster analysis showed that except for Syrah and Yan 73, the phenolic profiles in the tested grape cultivars had no significant year-to-year variations.
Microwave Multicomponent Synthesis
Authors: Hügel Helmut M.
Published: December 2009

In the manner that very important research is often performed by multidisciplinary research teams, the applications of multicomponent reactions involving the combination of multiple starting materials with different functional groups leading to the higher efficiency and environmentally friendly construction of multifunctional/complex target molecules is growing in importance. This review will explore the advances and advantages in microwave multicomponent synthesis (MMS) that have been achieved over the last five years.
Combination Therapy with Olmesartan and Amlodipine in the Treatment of Hypertension
Authors: Niemeijer Menco  G. , Cleophas Ton  J.
Published: December 2009

Background: Combination therapy with antihypertensive agents utilises different mechanisms of action and may be responsible for a more effective decrease in blood pressure. Objective: To review the recently published trials on efficacy and safety of the combination therapy with olmesartan and amlodipine. Results: The double-blind American COACH (Combination of Olmesartan Medoxomil and Amlopdine Besylate in Controlling High Blood Pressure) study (2008) showed in 1,940 patients that after eight weeks of treatment the BP goals were most frequently achieved in the ‘combination therapy group’, with 56.3% (54.1–58.5%) and 54.0% (51.8–56.2%) of patients reaching adequate blood pressure of
HF Radar Bistatic Measurement of Surface Current Velocities: Drifter Comparisons and Radar Consistency Checks
Authors: Lipa Belinda , Whelan Chad , Rector Bill , Nyden Bruce
Published: December 2009

We describe the operation of a bistatic HF radar network and outline analysis methods for the derivation of the elliptical velocity components from the radar echo spectra. Bistatic operation is illustrated by application to a bistatic pair: Both remote systems receive backscattered echo, with one remote system in addition receiving bistatic echoes transmitted by the other. The pair produces elliptical velocity components in addition to two sets of radials. Results are compared with drifter measurements and checks performed on internal consistency in the radar results. We show that differences in drifter/radar current velocities are consistent with calculated radar data uncertainties. Elliptical and radial velocity components are demonstrated to be consistent within the data uncertainties. Inclusion of bistatic operation in radar networks can be expected to increase accuracy in derived current velocities and extend the coverage area.