bluuebunny/crossref_metadata_2025 huggingface dataset:
Determination of Optimal Conditions for Addition of Foam to Steam for Conformance Control
Authors: Etminan S. Reza , Goldman Jon , Wassmuth Fred
Published: March 2016

Heat is transferred into the heavy oil reservoirs through steam injection. It reduces the viscosity of the heavy oil and bitumen and makes them mobile for production. Steam oil ratio (SOR) directly affects the cost of operation and is an index of the process efficiency. Steam processes could be optimized through addition of chemical additives to steam to selectively prohibit unfavorable channeling, gravity override and steam loss to the high permeable thief zones. Injection of foam with steam for conformance control is considered as a solution for increasing steam flooding efficiency and optimizing reservoir performance.

In this experimental study, a candidate surfactant is used to evaluate the optimal conditions for steam- foam application. Through a separate dedicated screening study at steam condition, one surfactant was identified which passed the required tests on solubility in injecting brine, foam generation, foam stability, surfactant thermal stability and its loss to reservoir rock surface, due to adsorption. This surfactant was co-injected in aqueous phase with steam to produce foam in porous medium. Core flooding tests were conducted at 260°C to evaluate the performance of foam with steam. The focus of this study was on determination of the optimal foam performance in different steam qualities and injection rates using steam (not non-condensable gases). Our tests were conducted in absence of oil and in a 30-cm core of less than 5 mD. Foam performance was monitored through differential pressures along the core as well as analysis of the foam in the effluent. Mobility Reduction Factor (MRF) allowed us to compare the performance of foam steam with steam-only process.

Shear velocities of as high as velocity at well perforations and as low as one meter per day were considered and tested at different steam qualities. The range of steam qualities tested was from 3 5% all the way to 100%, which was a slug-format test. Our candidate surfactant produced most foam around 50% quality which seems to be a good balance between the proportion of gas and liquid that produce stable foam texture. Higher qualities leads to drying out the lamella and lower qualities do not introduce sufficient gas to liquid for foam generation. Our tests reveal that there is a critical velocity beyond which foam generation starts and the foam and surfactant fronts are moving separately. MRFs of larger than 10 was determined in our optimal conditions.

Different steam qualities are tested in this study using real steam which condenses due to pressure rise along the core. Through these tests, operators could add significantly to their knowledge on how to best operate in adding foam to steam for a better reservoir performance.
Methodology of Foam-Surfactant EOR for Pilot Design Studies in Naturally Fractured Reservoirs
Authors: Abbaszadeh M. , Rodriguez De-La Garza F. , Villavicencio A.E.
Published: March 2016

This paper presents a novel foam-assisted surfactant Chemical Enhanced Oil Recovery (CEOR) of the matrix oil in naturally fractured reservoirs. Foam reduces fluid mobility within fractures and diverts the injected surfactant solution into matrix for wettability alteration and IFT reduction. Single–well cyclic huff-n-puff and dual completion pilots are modeled to evaluate the effectiveness of this envisioned CEOR, assess process mechanisms and demonstrate recovery conformance. In order to perform these foam-surfactant injection studies, a dual porosity-dual permeability 3-D sector model of the gas cap in a fractured reservoir is constructed, and co-injections of foaming surfactant in the nitrogen gas stream are simulated. These pilot simulations implement a laboratory-based surfactant phase behavior and foam model along with a compositional technique that captures surfactant-oil-brine phase behavior and tracks IFT and rheology of microemulsion phases. Sensitivity studies to various CEOR process mechanisms, injectivity characteristics, reservoir parameters and conformance are explored to guide an optimized pilot design scheme within operational constraints to evaluate and monitor the extent of oil recovery efficiency. The results show that while only a fraction of the released matrix oil is captured in the pilot arrangements due to conformance, considerable volumes of oil drain from the gas cap matrix blocks down to the oil column, thus substantiating the applicability of this envisioned foam-surfactant CEOR for naturally fractured reservoirs. Cyclic huff-n-puff injection is shown to be a more appropriate configuration for single-well pilot testing.
The Chronology of Steam Piloting in the Rubble Heavy Oil Reservoir, Awali Field, Bahrain
Authors: Al Balushi Aamer , Mohamed Ali , Stearns Stanley
Published: March 2016

Due to the complex geological nature of naturally fractured reservoirs (NFRs), their development is often associated with a lot of challenges, especially when it comes to improved oil recovery (IOR)/enhanced oil recovery (EOR) processes, where certain fluids are injected into the reservoir with the aim of increasing the recovery factor. If a large enough contrast in permeability between the rock's matrix and the fractures exists, which is often the case, fractures will dominate the flow, leading to a poorly processed matrix and eventually a poor recovery factor. The Rubble reservoir is one of the shallowest reservoirs in the long-producing Bahrain field that was discovered in 1932 as the first oil discovery in the Gulf Cooperation Council (GCC) region. With the majority of oil in place categorized as heavy oil, it was decided that a steam pilot would be implemented in 2011. Steam piloting in the Rubble reservoir has gone through multiple stages since 2011, and different thermal recovery processes have been tested using vertical, deviated, and horizontal wells.

The initial pilot tested cyclic steam stimulation (CSS) using high-pressure steam injection and low-pressure production in vertical wells, which was successful in mobilizing oil from the low-permeability Rubble reservoir. Based on the initial technical success, the CSS pilot was expanded to 17 additional wells drilled on three well pads in different parts of the field with different reservoir properties. The CSS expansion pilot also mobilized oil from the reservoir. Subsequently, continuous steam injection and offset oil production were attempted in two of the steam pilot pads. CSS was also attempted in horizontal wells; however, although oil was mobilized, the produced rates and volumes were not enough to have a low steam/oil ratio (SOR). These efforts ultimately led to the forced imbibition (FIM) pilot. In this current pilot, steam is simultaneously injected into three parallel, closely spaced horizontal wells and then produced simultaneously using large pumping units to reduce the bottomhole pressure to a minimum.

Results have been encouraging, with SORs of less than 4 barrels of steam per barrel of oil (bs/bo). FIM has proved to be the most promising steam EOR process attempted in the Rubble reservoir.

This paper examines the results of the Rubble steam pilot stages, highlights the challenges faced in each stage, and presents our evolved understanding of the physical processes involved as the pilot progressed.
Foam Propagation in Rock Samples: Impact of Oil and Flow Caracterization
Authors: Batôt G. , Fleury M. , Rosenberg E. , Nabzar L. , Chabert M.
Published: March 2016

Foams are among the most promising and cost effective means to alleviate the drawbacks associated with gas-based EOR-processes. The objective of this work is to probe the impact of residual oil saturation on CO2-foam generation and on their flow behavior in porous media

Designing a foam-EOR process requires its evaluation and optimisation at laboratory scale using coreflood tests. However, such coreflood tests are usually performed on relatively long core sample, this lead to long time-consuming experiments. In this study are presented results using both long and short coreflood systems. Short coreflood systems (allowing short-duration test) are coupled to a NMR apparatus and to an CT-scanner that allow live and non-invasive measurements of the fluids saturation.

In a first part of this work, the efficiencies of two proprietary formulations to generate stable foam in porous media under reservoir conditions and in absence of oil have been compared. We used a coreflood set-up equipped with X-Ray detection to monitor gas propagation inside relatively long core samples. Then, their ability to resist the oil (Dodecane) have been evaluated and compared. The results evidenced two largely different behaviors. One of the two formulations resists the presence of oil up to an oil saturation of 35-40% while the second is destabilized as soon as the oil saturation exceeds 20%. Both formulations were insensitive to oil bellow an oil saturation of 15%. Depending on the application targeted, this laboratory evaluation should be coupled with a detailed economic evaluation to select the formulation to be used.

In a second part, we performed co-injection tests using NMR small coreflood set-up and IRM-scanner in absence of oil. They brought more detailed information regarding fluid saturations that help interpreting foam characteristics and flow behavior in porous media.
Steam Piloting in the Aruma Reservoir, Awali Field, Bahrain
Authors: Stearns Stanley , Mohamed Ali , Al Balushi Aamer
Published: March 2016

The Aruma formation is the shallowest hydrocarbon-bearing reservoir in the Bahrain field. It contains heavy oil and bitumen irregularly distributed in fractured and vuggy carbonate rocks, making reservoir characterization and hydrocarbon production particularly challenging. The best analog for the Aruma accumulation is the Grosmont bitumen accumulation in Canada, where bitumen is also present in fractures and vugs in carbonate rocks. A field test of cyclic steam stimulation (CSS) in the Aruma formation was implemented in November 2014. The primary objective of the Aruma CSS pilot was to prove that it is possible to mobilize heavy oil and bitumen in the Aruma reservoir and produce it to the surface. This pilot objective was achieved.
Micromorphology and histochemistry of leaf trichomes of Salvia aegyptiaca (Lamiaceae)
Authors: Janosevic Dusica , Budimir Snezana , Alimpic Ana , Marin Petar , Al Sheef , Giweli Abdulhmid , Duletic-Lausevic Sonja
Published: March 2016

We performed a comprehensive study of trichomes considering the medicinal
importance of the essential oils produced in glandular trichomes of Salvia
aegyptiaca L. and lack of data about leaf trichome characteristics.
Micromorphological and histochemical analyses of the trichomes of S.
aegyptiaca were carried out using light and scanning electron microscopy. We
report that the leaves contained abundant non-glandular unbranched trichomes
and two types of glandular trichomes, peltate and capitate, on both leaf
surfaces. The abaxial leaf side was covered with numerous peltate and
capitate trichomes, while capitate trichomes were more abundant on the
adaxial leaf side, where peltate trichomes were rarely observed. The
non-glandular trichomes were unicellular papillae and multicellular,
uniseriate, two-to-six-celled, erect or slightly leaning toward the
epidermis. Peltate trichomes were composed of a basal cell, a short
cylindrical stalk cell and a broad head of eight secretory cells arranged in
a single circle. Capitate trichomes consisted of a one-celled glandular head,
subtended by a stalk of variable length, and classified into two types:
capitate trichomes type I (or short-stalked glandular trichomes) and capitate
trichomes type II (or long-stalked glandular trichomes). Histochemical tests
showed that the secreted material in all types of S. aegyptiaca glandular
trichomes was of a complex nature. Positive reactions to lipids for both
types of glandular trichomes were obtained, with especially abundant
secretion observed in peltate and capitate trichomes type II.
A New Receptive Vocabulary Size Test for French
Authors: Batista Roselene , Horst Marlise
Published: March 2016

Researchers have developed several tests of receptive vocabulary knowledge suitable for use with learners of English, but options are few for learners of French. This situation motivated the authors to create a new vocabulary size measure for French, the Test de la taille du vocabulaire (TTV). The measure is closely modelled on Nation’s (1983) Vocabulary Levels Test (VLT) and follows the guidelines written by Schmitt, Schmitt, and Clapham (2001). Initially, a pilot version was trialled with 63 participants; then an improved version was administered to 175 participants at four proficiency levels. Results attest to the TTV’s validity: mean scores across the four frequency sections decreased as the tested words became less frequent, and more proficient learner groups outperformed less proficient groups. The TTV in its current form is intended to be of practical use to teachers and learners, but it is also expected to evolve; ideas for future improvements are discussed.
Qualitative and Quantitative Analysis of Microbial Communities in Household Dishwashers in Germany
Authors: Brands Britta , Honisch Marlitt , Merettig Nadine , Bichler Sandra , Stamminger Rainer , Kinnius Jörg , Seifert Monika , Hardacker Ingo , Kessler Arnd , Weide Mirko , Wrubbel Noelle , Bockmühl Dirk P.
Published: March 2016

The proper cleaning of used dishes provides an essential means to maintain a sufficient hygiene level on food contact surfaces. However, little is known on the microbiological quality of domestic dishwashers themselves, especially in relation to consumer habits. This study investigated dishwashers in German households to analyse the number and composition of microbial colonisers and their putative impact on dishwashing hygiene. Although the microbiological status of dishwashers appeared to depend on multiple factors, data suggest that a trend towards lower temperatures might effect in a decreased hygiene.
Synthesis, Surface Activity and Application Properties of a Novel Ethoxylated Gemini Trisiloxane Surfactant
Authors: Peng Zhongli , Zeng Hui
Published: March 2016

A novel ethoxylated gemini trisiloxane surfactant B whose general formula is of RO(CH2CH2O)8.7R [R = Me3SiOSiMe(CH2)3 · OSiMe3] has been synthesized using polyethylene glycol 400, 3-chloropropylene and 1,1,1,3,5,5,5-heptamethyltrisiloxane as main raw materials. This compound was structurally characterized by ESI-MS, 1H-NMR and 13C-NMR spectroscopy. Its surface activity and application properties containing spreading performance and hydrolysis resistance were also measured. The critical aggregation concentration (CAC) and the surface tension of surfactant B solution at CAC (γCAC) of are 2.63 × 10−6 mol L−1 and 20.7 mN m−1, respectively. This CAC is only one-tenth of the CAC of the Υ-shaped ethoxylated double-tail trisiloxane surfactant 1P, where CAC was replaced with critical micelle concentration (CMC), indicating that surfactant B has an extremely high surface activity. The spreading ability (SA) of its solution (5 × 10−3 mol L−1) within 1 min over Parafilm, PE film and ficus microcarpa leaves is 23.9, 45.7 and 59.8, respectively, suggesting that this surfactant has a better SA than 1P and possesses superspreading. This surfactant also possesses a stronger hydrolysis resistance than 1P; for instance, in pH 10.0 environment for 86 days. The surface tension of surfactant B solution has been no more than 6 percent of its initial value. It is suggested that the excellent interfacial properties of surfactant B is related to its U-shaped conformation in water.
Synthesis and Surface Active Properties of Novel Oligomer Betaine Surfactants
Authors: Zhou Ming , Huang Zhou , Yu Shuang , Yang Yan , Huang Yongsheng , Qiu Dan , Zhao Jinzhou
Published: March 2016

A new type of oligomer betaine surfactants pentasodium N,N′,N″-alkyl diethylene triamine pentaacetic acid containing five carboxylate groups, three quaternary ammonium groups and three hydrophobic groups was synthesized by alkaline neutralization reaction and quaternization with diethylene triamine pentaacetic acid, sodium hydroxide and long chain alkyl bromide as main raw materials. The chemical structures of the prepared compounds were confirmed by FTIR, 1H NMR, MS spectroscopy and elementary analysis. With the increasing length of the carbon chain, the CMC of the synthesized compounds initially decreased. The surface active properties of these compounds were superior to that of the single chain betaine surfactants rich as decyl dimethyl betaine. The efficiency of adsorption at the water/air interface (pC20) of these surfactants was very high. It is found that the shorter hydrocarbon chain length of oligomer betaine surfactants, the faster the rate of reduction of surface tension, and the bigger the aggregation number of oligomer betaine surfactants are. Their foaming properties and wetting ability toward a felt chip, and lime-soap dispersing ability were investigated.
Preparation of a Multifunctional Terpolymer Inhibitor for CaCO3 and BaSO4 in Oil Fields
Authors: Liu Yanmei , Zhou Yuming , Yao Qingzhao , Wang Huchuan , Wu Zhen , Chen Yiyi , Liu Liu , Yang Chongyang , Wu Wendao , Sun Wei
Published: March 2016

The aim of this paper is to inhibit the formation of calcium carbonate and barium sulfate scales which are common but unwanted crystalline products in the production of oil from off-shore rigs. A multifunctional antiscalant APES/AA/AMPS was prepared by reaction of acrylic acid, ammonium allylpolyethoxy sulphate and 2-acrylamido-2-methyl-propanesulfonic acid with different molar ratios. The experimental results showed that the polymer has high performance towards scales, nearly 90 % for CaCO3 and 87 % for BaSO4 respectively by static scale inhibition tests. The crystals of scales were characterized by using scanning electron microscopy and X-ray powder diffraction. According to the changes of the crystal shape, size and morphology, the inhibition mechanisms of complexation and adsorption between the inhibitor and the crystal surface were proposed.
Interactions of Cellulase and Oleic Acid Solution Mixtures
Authors: Yehia Ahmed , El-Halim Sawsan Abd , Sharada Hayat , Khalek Mohamed Abdel , Ammar Mayar
Published: March 2016

The interaction of oleic acid, as an anionic detergent, with cellulase has been investigated using different techniques (surface tension, turbidity and FTIR). The surface tension measurements show that the CMC of the oleic acid-cellulase mixture is lower than that of the individual components. The interaction in this case is defined as attractive and the mixture exhibits synergism. Also, it is found that the area per molecule for the oleic acid/cellulase mixed isotherm is lower than area of the pure oleic acid. This decrease in the area/molecule is due to the arrangement of cellulase molecules in-between the oleic acid chains. Turbidity measurements indicate the formation of two complexes. Complex 1 is obtained at low oleic concentrations (< 10−4 M) with compact size giving a high turbidity. Complex 2 is formed at higher oleic concentrations (> 10−4 M) where the formed aggregates were precipitated and the turbidity was decreased. The changes in the FTIR spectrum features of cellulase after oleic acid addition indicate an interaction between cellulase and oleic acid in their mixture.
Experimental studies in a single-phase parallel channel natural circulation system: preliminary results
Authors: Bodkha K. , Pilkhwal D. S. , Jana S. S. , Vijayan P. K.
Published: March 2016

Natural circulation systems find extensive applications in industrial engineering systems. One of the applications is in nuclear reactor where the decay heat is removed by natural circulation of the fluid under off-normal conditions. The upcoming reactor designs make use of natural circulation in order to remove the heat from core under normal operating conditions also. These reactors employ multiple vertical fuel channels with provision of on-power refueling/defueling. Natural circulation systems are relatively simple, safe and reliable when compared to forced circulation systems. However, natural circulation systems are prone to encounter flow instabilities which are highly undesirable for various reasons. Presence of parallel channels under natural circulation makes the system more complicated. To examine the behavior of parallel channel system, studies were carried out for single-phase natural circulation flow in a multiple vertical channel system. The objective of the present work is to study the flow behavior of the parallel heated channel system under natural circulation for different operating conditions. Steady state and transient studies have been carried out in a parallel channel natural circulation system with three heated channels. The paper brings out the details of the system considered, different cases analyzed and preliminary results of studies carried out on a single-phase parallel channel system.
Protactinium-231 as a new fissionable material for nuclear reactors that can produce nuclear fuel with stable neutron-multiplying properties
Authors: Shmelev A. N. , Kulikov G. G. , Kulikov E. G. , Apse V. A.
Published: March 2016

Main purpose of the study is justifying doping of protactinium-231 into fuel compositions of advanced nuclear reactors with the ultimate aim to improve their operation safety and economic efficiency. Protactinium-231 could be generated in thorium blankets of hybrid thermonuclear facilities. The following results were obtained: 1. Protactinium-231 has some favorable features for its doping into nuclear fuel; 2. Protactinium containing fuel compositions can be characterized by the higher values of fuel burn-up, the longer values of fuel lifetime and the better proliferation resistance; 3. as protactinium-231 is the stronger neutron absorber than uranium-238, remarkably lower amounts of protactinium-231 may be doped into fuel compositions. The free space could be occupied by materials which are able to improve heat conductivity and refractoriness of fuel. As a consequence, operation safety of nuclear reactors could be upgraded.
Structural and mechanical study on Mg–xLM (x = 0–5 wt.%, LM = Sn, Ga) alloys
Authors: Kubásek Jiří , Vojtěch Dalibor , Dvorský Drahomír
Published: March 2016

Low-melting point metals, such as Sn and Ga, can improve both the mechanical and corrosion properties of pure Mg. Currently, Mg–Sn based alloys are being considered for high-temperature applications, and both Mg–Sn and Mg–Ga based alloys are also being considered as possible candidates for biodegradable materials. Although these binary systems have already been the subject of research, only limited information on their characteristics has been published. Therefore, as-cast Mg–Sn and Mg–Ga alloys containing 1, 3.5 and 5 wt.% of alloying elements were studied in the present work. Moreover, the effect of extrusion on Mg–Sn and Mg–Ga alloys containing 3.5 wt.% of the alloying element was studied. Structural and chemical analyses of the alloys were performed by using light and scanning electron microscopy, energy dispersive spectrometry and X-ray diffraction. The mechanical properties were determined by Vickers hardness measurements and tensile and compressive testing. The as-cast alloys were characterized by a dendritic morphology with the presence of secondary eutectic phases. Both Sn and Ga exhibited hardening and strengthening effects on magnesium. The extruded alloys were characterized by fine-grained microstructures with a grain size of approximately 3 and 6 μm for Mg-3.5Sn and Mg-3.5Ga alloys, respectively, and significantly improved mechanical properties compared with the as-cast state. The ultimate tensile strength reached almost 250 MPa for both extruded alloys compared with 120–150 MPa for the as-cast condition. The results indicate that Mg–Sn- and Mg–Ga-based alloys appear to be suitable candidates for both engineering and medical applications.
Use of Agent-Based Crowd Simulation to Investigate the Performance of Large-Scale Intermodal Facilities: Case Study of Union Station in Toronto, Ontario, Canada
Authors: Hoy Gregory , Morrow Erin , Shalaby Amer
Published: March 2016

When planning complex transit terminals, hubs, and stations, it is critical to analyze a facility’s capacity to handle expected passenger movements and volumes. In Toronto, Ontario, Canada, the revitalization of Union Station, the country’s busiest transit facility, involved the development of a set of high-fidelity pedestrian microsimulation models that were used to plan the improvement of this major intermodal hub. The pedestrian models were first created with MASSMOTION software, and construction plans and projected transit schedules were applied to represent various scenarios during and after the station revitalization. These models were then calibrated and validated against data from passenger counts and transit usage surveys to provide an accurate base for future scenarios. Through the use of a fully constructed model of the station with 2031 transit demand projections, a series of stress experiments was performed to evaluate the station’s capability to handle future passenger volumes. Under projected 2031 circumstances, it was found that Union Station could operate reasonably well. However, an increase in inbound transit passenger volumes of a mere 10% over 2031 projections could lead to severe levels of congestion within constrained sections of the station. This paper reports on the development of the microsimulation models and the model results for future scenarios.
Using Parametric Modeling to Estimate Highway Construction Contract Time
Authors: Zhai Dong , Shan Yongwei , Sturgill Roy E. , Taylor Timothy R. B. , Goodrum Paul M.
Published: March 2016

Federal regulations require that state transportation agencies have written procedures for setting the construction contract time for highway projects. Since the institution of those regulations, state agencies have used a variety of methods to estimate and set contract time. FHWA recommends the use of methods based on production rate and activity precedence and logic in this process. For years, the Kentucky Transportation Cabinet used a system based around these requirements and recommendations only to find that the system produced estimates varying widely from actual construction times. The use of parametric modeling and historic contract times produced a system that more accurately estimates contract times and with an associated Microsoft Excel–based tool is more user friendly. This approach used project cost and bid item quantity data in multivariate regression–based modeling to develop a set of equations that provide the Kentucky Transportation Cabinet with contract time estimates for projects in a matter of minutes by using data readily available at later design stages.
New Approach to Determining Concrete Slab Lift-Off by Use of Interfacial Fracture Mechanics Concepts
Authors: Mirsayar M. M. , Huang Kaijian , Zollinger Dan G.
Published: March 2016

Negative temperature gradient and the moisture gradient through the thickness of a concrete slab result in curling and warping of the slab edges to a concave configuration. The tendency of the slab pavement to separate from the subbase layer, called lift-off, is mainly controlled by such environmental effects and the weight of the slab itself. Because of such effects, cracks may propagate at the interface of the concrete slab and the subgrade. The induced stress and displacement fields around the interface crack tip are characterized by the stress intensity factors. The stress intensity factors can then be used in assessment of the cracked bond strength by employing any fracture criteria; therefore, it is necessary that the stress intensity factors be obtained. This paper proposes a new approach for determination of slab lift-off that uses concepts from interfacial fracture mechanics. A two-dimensional finite element analysis was performed to simulate lift-off in concrete slab pavements, and the effect of interface cracking on the mechanism of the lift-off was investigated. The relative stress intensity factors as well as the relative slab lift-off were determined for different crack lengths, loading conditions, and material properties of the slab and the subgrade. The presented model was validated with experiments. This paper discusses the remarkable effects of the material properties and the induced contraction stress on the slab lift-off. The findings presented provide researchers with some insight as to the effect of curing conditions and relative stiffness on slab lift-off and answer some of the primary questions regarding the mechanism of interfacial fracture in concrete slab–subgrade structures caused by the lift-off.
Quantitative Assessment of the Effect of Wide-Base Tires on Pavement Response by Finite Element Analysis
Authors: Gungor Osman Erman , Hernandez Jaime A. , Gamez Angeli , Al-Qadi Imad L.
Published: March 2016

Various studies have shown that the new-generation wide-base tire (WBT) for trucks causes more damage to pavement than does the dual-tire assembly (DTA). However, there is no substantive approach that quantifies the difference in pavement responses produced by WBTs and the DTA. This study filled this gap by developing linear equations that connect pavement responses produced by these two tire types. Equations were developed for 10 different pavement responses through 480 finite element method simulations (240 for the DTA and 240 for WBTs) that were run in ABAQUS with the same material properties and pavement structures. The only difference was the contact stresses and contact areas that were measured under the same axle load for WBTs and the DTA. The cases modeled in simulations were selected to capture extreme conditions, that is, thick and thin pavement structures with strong and weak material properties. The equations will help pavement researchers to understand quantitatively the effect of WBTs on pavement responses as compared with the DTA. The low resultant prediction error, 10%, allows linear equations to be implemented through the application of adjustment factors on mechanistic pavement design guides such as the Mechanistic–Empirical Pavement Design Guide, which are unable to simulate WBT loading realistically. To predict pavement damage accurately, the pavement analysis should consider the WBT market penetration in the United States (approximately 10%) and the partial use of WBTs on truck axles. The impact of WBTs on pavement should be evaluated in the context of economic and environmental benefits.
The Capital and the Romantic Sublime: The Case of Thomas De Quincey
Authors: Veliki Martina Domines
Published: March 2016

This paper aims to explore the idea that the formulation of the modern discipline of economics involved a discourse on the romantic sublime. By using the example of Thomas De Quincey's Confessions of an English Opium-Eater (1821), it will address the issue of money and knowledge as two formative experiences in De Quincey's life. Unlike his literary model, William Wordsworth, who is eager to build up his ‘egotistical sublime’ (Keats's phrase), De Quincey is intent on registering his traumatic memories and resultant disorders and neuroses. Thus, he builds up a new type of romantic subjectivity where his personal accumulation of debt can be read as an encounter with the sublime, and it runs parallel to Britain's ever-increasing national debt. The sublime in De Quincey's Confessions carries an ideological burden as it affirms the subsistence of a middle-class individual and his right to participate in the discourse of the sublime. However, De Quincey falls from his middle-class position and becomes one of the poor where his access to the sublime experience is utterly denied. De Quincey's London experience is measured against Wordsworth's London experience in The Prelude (1805) and by experiencing the ‘negative sublime’ (Weiskel), he puts Wordsworthian ethics into practice. Thus, De Quincey's Confessions shows the tensions inherent in the romantic discourse of the sublime in a manner which connects romantic modes of subjectivity to the rising capitalist society.
Exploring misery discourses: problematized Roma in labour market projects
Authors: Vesterberg Viktor
Published: March 2016

The aim of this article is to analyse learning practices in labour market projects cofinanced by the European Social Fund (ESF) targeting unemployed Roma in Sweden. The empirical material consists of 18 project descriptions from ESF projects, as well as national and European policy documents concerned with the inclusion of the Roma in contemporary Europe. The contemporary empirical material is analysed in relation to a government report from 1956 concerning the ‘Roma issue’ in Sweden. The analytical perspective of the study is governmentality, and the analysis focuses on different kinds of problematizations and the discursive positioning of the Roma subjects. One of the main findings is that unemployed Roma are situated in various discourses of misery and constructed as in need of reshaping their subjectivities in order to become educable as well as employable.
Constructing Frozen Jacobian Iterative Methods for Solving Systems of Nonlinear Equations, Associated with ODEs and PDEs Using the Homotopy Method
Authors: Qasim Uswah , Ali Zulifqar , Ahmad Fayyaz , Serra-Capizzano Stefano , Zaka Ullah Malik , Asma Mir
Published: March 2016

A homotopy method is presented for the construction of frozen Jacobian iterative methods. The frozen Jacobian iterative methods are attractive because the inversion of the Jacobian is performed in terms of LUfactorization only once, for a single instance of the iterative method. We embedded parameters in the iterative methods with the help of the homotopy method: the values of the parameters are determined in such a way that a better convergence rate is achieved. The proposed homotopy technique is general and has the ability to construct different families of iterative methods, for solving weakly nonlinear systems of equations. Further iterative methods are also proposed for solving general systems of nonlinear equations.
Review of Recent Advances in the Application of the Wavelet Transform to Diagnose Cracked Rotors
Authors: Gómez María , Castejón Cristina , García-Prada Juan
Published: March 2016

Wavelet transform (WT) has been used in the diagnosis of cracked rotors since the 1990s. At present, WT is one of the most commonly used tools to treat signals in several fields. Understandably, this has been an area of extensive scientific research, which is why this paper aims to summarize briefly the major advances in the field since 2008. The present review considers advances in the use and application of WT, the selection of the parameters used, and the key achievements in using WT for crack diagnosis.
Melanoma Cancer Stem Cells: Markers and Functions
Authors: Parmiani Giorgio
Published: March 2016

The discovery of cancer stem cells (CSCs) in human solid tumors has allowed a better understanding of the biology and neoplastic transformation of normal melanocytes, and the possible mechanisms by which melanoma cells acquire tumorigenicity. In this review I summarize the literature findings on the potential biomarkers of melanoma CSCs, their presence in the melanoma cell populations, the interaction with the immune system (with both T and NK cells) and the role of melanoma CSCs in the clinics. Given the extraordinary progress in the therapy of melanoma caused by immune checkpoint antibodies blockade, I discuss how these antibodies can work by the activation of melanoma infiltrating T cells specifically recognizing neo-antigens expressed even by melanoma CSCs. This is the mechanism that can induce a regression of the metastatic melanomas.
Turn on Fluorescent Probes for Selective Targeting of Aldehydes
Authors: Dilek Ozlem , Bane Susan
Published: March 2016

Two different classes of fluorescent dyes were prepared as a turn off/on sensor system for aldehydes. Amino derivatives of a boron dipyrromethene (BDP) fluorophore and a xanthene-derived fluorophore (rosamine) were prepared. Model compounds of their product with an aldehyde were prepared using salicylaldehyde. Both amino boron dipyrromethene and rosamine derivatives are almost non-fluorescent in polar and apolar solvent. However, imine formation with salicylaldehyde on each fluorophore increases the fluorescence quantum yield by almost a factor of 10 (from 0.05 to 0.4). These fluorophores are therefore suitable candidates for development of fluorescence-based sensors for aldehydes.
Long-Range Electron Transport Donor-Acceptor in Nonlinear Lattices
Authors: Chetverikov Alexander , Ebeling Werner , Velarde Manuel
Published: March 2016

We study here several simple models of the electron transfer (ET) in a one-dimensional nonlinear lattice between a donor and an acceptor and propose a new fast mechanism of electron surfing on soliton-like excitations along the lattice. The nonlinear lattice is modeled as a classical one-dimensional Morse chain and the dynamics of the electrons are considered in the tight-binding approximation. This model is applied to the processes along a covalent bridge connecting donors and acceptors. First, it is shown that the electron forms bound states with the solitonic excitations in the lattice. These so-called solectrons may move with supersonic speed. In a heated system, the electron transfer between a donor and an acceptor is modeled as a diffusion-like process. We study in detail the role of thermal factors on the electron transfer. Then, we develop a simple model based on the classical Smoluchowski–Chandrasekhar picture of diffusion-controlled reactions as stochastic processes with emitters and absorbers. Acceptors are modeled by an absorbing boundary. Finally, we compare the new ET mechanisms described here with known ET data. We conclude that electron surfing on solitons could be a special fast way for ET over quite long distances.
Timing Foreign Exchange Markets
Authors: Malone Samuel , Gramacy Robert , Ter Horst Enrique
Published: March 2016

To improve short-horizon exchange rate forecasts, we employ foreign exchange market risk factors as fundamentals, and Bayesian treed Gaussian process (BTGP) models to handle non-linear, time-varying relationships between these fundamentals and exchange rates. Forecasts from the BTGP model conditional on the carry and dollar factors dominate random walk forecasts on accuracy and economic criteria in the Meese-Rogoff setting. Superior market timing ability for large moves, more than directional accuracy, drives the BTGP’s success. We explain how, through a model averaging Monte Carlo scheme, the BTGP is able to simultaneously exploit smoothness and rough breaks in between-variable dynamics. Either feature in isolation is unable to consistently outperform benchmarks throughout the full span of time in our forecasting exercises. Trading strategies based on ex ante BTGP forecasts deliver the highest out-of-sample risk-adjusted returns for the median currency, as well as for both predictable, traded risk factors.
Measuring the Actual Energy Cost Performance of Green Buildings: A Test of the Earned Value Management Approach
Authors: Dwaikat Luay , Ali Kherun
Published: March 2016

Reduced energy consumption is a key aspect of the green building. Nonetheless, research indicates that there is a performance gap between the predicted and the actual energy performance once buildings are occupied, which implies a cost deviation from the anticipated energy cost performance. However, the cost deviation also might result from lower or higher energy rates than expected. As an appropriate research methodology for existing theory testing, case study research strategy was adopted to empirically examine the earned value management (EVM) approach to measure the actual life cycle cost performance of energy in green buildings. With slight methodological and terminological adaptations, it is found that the EVM approach can be applied to conduct a holistic cost performance measurement of the actual energy consumption in green buildings. The strength of the earned value approach is that it allows for detecting whether the energy cost saving or overrun results from lower or higher energy consumption, or from actual energy rate variations. The earned value approach allows for quantifying each cost variance independently, which is a significant aspect of actual energy cost performance measurement in green buildings.
Edge Influence on Diversity of Orchids in Andean Cloud Forests
Authors: Parra Sánchez Edicson , Armenteras Dolors , Retana Javier
Published: March 2016

Cloud forests harbor high levels of orchid diversity. However, due to the high fragmentation of these forests in the Andes, combined with the pressure for new agricultural land, orchid diversity is highly threatened. Despite this worrying scenario, few studies have assessed the effects of habitat loss specifically on orchid assemblages in the Andes. The aim of this study was to analyze the edge effect on orchids in cloud forest fragments of varying size. We measured forest structure, neighboring land cover and edge effect on orchid abundance, species richness and beta-diversity, by sampling assemblages along edge-to-interior transects in six different sized Andean (southwest Colombia) forest remnants. We recorded 11,127 stem-individuals of orchids in 141 species. Within the forest, edges sustained equal or more species than interior plots. Our results revealed neither patch metrics nor forest structure showed any significant association to orchid diversity at any scale. Nonetheless, from our observations in composition, the type of neighboring cover, particularly pastures, negatively influences interior species (richness and composition) in larger reserves. This might be due to the fact that some species found in interior plots tend to be confined, with sporadic appearances in regeneration forest and are very scarce or absent in pastures. Species richness differed significantly between matrix types. Our results suggest that (1) orchid diversity shows spatial variability in response to disturbances, but the response is independent from forest structure, patch size and patch geometry; (2) orchid communities are negatively affected by covers, and this pattern is reflected in reduced richness and high species turnover; (3) orchid richness edge effect across a pasture-interior gradient. Two forest management implications can be discerned from our results: (1) management strategies aiming to reduce edge effects may focus on improvement regeneration conditions around pasture lands; and (2) local scale management and conservation activities of natural forests in cloud forests will favor small reserves that harbor high levels of richness.
Improvement of Malvar Wine Quality by Use of Locally-Selected Saccharomyces cerevisiae Strains
Authors: Cordero-Bueso Gustavo , Esteve-Zarzoso Braulio , Gil-Díaz Mar , García Margarita , Cabellos Juan , Arroyo Teresa
Published: March 2016

Malvar grape juice offers relatively little in the way of a sensory experience. Our interest lies in the use of locally-selected yeast strains in experimental fermentations to improve the sensory characteristics of Malvar wines. Two locally-selected strains of Saccharomyces cerevisiae were used as starter cultures in vinifications and compared with spontaneous fermentations of the same cultivar musts. Wine quality was investigated by their principal oenological parameters, analysis of the volatile aroma components, and corroborated by an experienced taster panel. The most salient chemical attributes were its high concentrations of isoamyl acetate and hexyl acetate and the high acidity, which have been detected to be key constituents in setting the fruity and fresh character of Malvar wines. Winemakers of winegrowing areas where this grape variety is cultivated will have improved options to elaborate new white wines styles, using selected yeast strains that enhance its aromatic properties.
Breads Fortified with Freeze-Dried Vegetables: Quality and Nutritional Attributes. Part 1: Breads Containing Oil as an Ingredient
Authors: Ranawana Viren , Raikos Vassilios , Campbell Fiona , Bestwick Charles , Nicol Phyllis , Milne Lesley , Duthie Garry
Published: March 2016

There is increasing emphasis on reformulating processed foods to make them healthier. This study for the first time comprehensively investigated the effects of fortifying bread (containing oil as an ingredient) with freeze-dried vegetables on its nutritional and physico-chemical attributes. Breads fortified with carrot, tomato, beetroot or broccoli were assessed for nutrition, antioxidant potential, storage life, shelf stability, textural changes and macronutrient oxidation. Furthermore, using an in vitro model the study for the first time examined the impact of vegetable addition on the oxidative stability of macronutrients during human gastro-intestinal digestion. As expected, adding vegetables improved the nutritional and antioxidant properties of bread. Beetroot and broccoli significantly improved bread storage life. None of the vegetables significantly affected bread textural changes during storage compared to the control. Lipid oxidation in fresh bread was significantly reduced by all four types of vegetables whilst protein oxidation was lowered by beetroot, carrot and broccoli. The vegetables demonstrated varying effects on macronutrient oxidation during gastro-intestinal digestion. Beetroot consistently showed positive effects suggesting its addition to bread could be particularly beneficial.
Public Health Approaches and Barriers to Educating Providers about Hereditary Breast and Ovarian Cancer Syndrome
Authors: Trepanier Angela , Supplee Laura , Blakely Lindsey , McLosky Jenna , Duquette Debra
Published: March 2016

The Michigan Department of Health and Human Services implemented and evaluated two initiatives designed to enhance provider knowledge of patients appropriate for breast and/or ovarian cancer genetic risk assessment and hereditary breast and ovarian cancer (HBOC) syndrome testing. The first initiative targeted select providers who had diagnosed patients meeting HBOC risk criteria. Specifically, the initiative used 2008–2009 state cancer registry data to identify all providers who had diagnosed breast cancers in women ≤50 years of age, male breast cancers, and ovarian cancers in four health systems with newly established cancer genetics clinics. Using a method coined bidirectional reporting (BDR), reports highlighting how many of these cases each provider had seen were generated and mailed. Reports on 475 cancers (9.5% of the 5005 cases statewide meeting criteria) were sent to 69 providers with information about how and why to refer such patients for genetic counseling. Providers who received a report were contacted to assess whether the reports increased awareness or resulted in action (genetic counseling/referral). Based on the few responses received, despite multiple attempts to contact, and attrition rate, it is not possible to ascertain the impact of this initiative on providers. However the project resulted in the MDHHS identifying which providers see the largest proportion of at-risk patients, creating an opportunity to target those providers with HBOC education efforts. The second initiative involved creating and broadly disseminating an online, interactive case-based educational module to increase awareness and referral decisions for HBOC using high- and low-risk patient scenarios. A total of 1835 unique users accessed the module in a one year. Collectively the users viewed topic pages 2724 times and the interactive case studies 1369 times. Point of care tools (fact sheets) were viewed 1624 times and downloaded 764 times. Satisfaction among the subset of users applying for continuing medical education credit was high. The online educational module had a much broader reach than the bidirectional reporting initiative but to a self-selected audience. Combining targeted and broad-based provider education efforts may be a better way to increase HBOC awareness in the target audience, starting with those providers seeing the largest proportion of patients at risk.