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Geopolymer technology offers a sustainable alternative to energy-intensive cement production, potentially reducing dependence on natural resources and mitigating environmental impact. Silica fumes (SF) are mostly used to enhance the fresh, hardened, and durable performance of geopolymers. However, their influence on geopolymerization may result in the expansion of the geopolymer mortar (GPM) due to reaction with alkaline liquid. In this study, the effect of NaOH concentration, particle size and dosage of SF, alkaline liquid-to-binder ratio, Na2SiO3-to-NaOH ratio, and sand-to-binder ratio on the expansion behavior of a low calcium fly ash (FA)-based GPM was investigated. FA-based GPMs were tested using two distinct SFs with varying particle sizes (SF1 = 9.5 µm and SF2 = 16.2 µm) and two varying dosages of SF (2.5% and 5%). Physical observations of GPMs revealed that NaOH concentration, particle size and dosage of SF are crucial factors that significantly impact the expansion which is concomitant with a reduction in compressive strength. Analytical techniques such as X-ray diffraction (XRD), Rietveld analysis, Fourier transform infrared spectroscopy (FTIR), and Thermo Gravimetric Analysis (TGA) were employed to comprehensively investigate reaction product(s) that led to the expansion of such GPMs. The chemical analysis confirmed the presence of excess analcime in the mortars fabricated by blending SF1 and FA at 12 M NaOH concentration. This study is the first to report the expansion of low calcium FA-based GPMs blended with a SF of particle size 9.5 µm. These findings emphasize the significance of selecting the appropriate SF particle size to prevent expansion and ensure optimal compressive strength in geopolymer applications. [ABSTRACT FROM AUTHOR]

The reuse of by-products has become increasingly important as a means of minimising the consumption of natural resources and reducing waste disposal. This study examines the potential reuse of steel slag for soil stabilisation, with benefits such as conserving natural resources and mitigating the greenhouse gas emissions associated with the production of conventional stabilising agents. It focuses on evaluating the effect of pozzolanic reactions on the strength and stiffness of both loess silt and silt-bentonite mixtures. The experimental tests included the physical characterisation of granular materials, reactivity tests of the pozzolanicity of soil mixtures, compaction tests, unconfined compression tests, and hydraulic conductivity tests. The impact of the curing period was also analysed to quantify the effects of natural cementation and the development of hydrogels within soil pores on the compacted soil properties. The findings suggest that adding steel slag can significantly increase the strength and the stiffness of compacted loess silts by over 300% and 500%, respectively, after 56 days of curing, substantially reducing the hydraulic conductivity of granular materials, such as the tested silt, as hydrogels partially occupy the pores available for liquid flow. It should be noted that the chemical reactions during hydrogel formation may hinder the free expansion of clay mixtures and release Ca2+ ions, thereby counteracting the expected reduction in hydraulic conductivity when bentonite is added to compacted earthen barriers. [ABSTRACT FROM AUTHOR]

The application of seawater concrete is receiving increasing attention due to the advantage of using seawater in alleviating water scarcity. One concern with seawater concrete applications is the potential for alkali–silica reaction (ASR) due to the elevated alkali concentration. In this paper, the ASR risk induced by mixed seawater in cement mortar incorporating non-reactive or reactive aggregates (RAs) was studied through short-term and long-term experiments. Experimental results indicate that seawater only increased ASR in the presence of RAs due to the high alkali concentration. Replacing cement with 70% ground granulated blast-furnace slag (GGBS) prevented expansion, although very few ASR products may be observed. SEM results indicated that seawater decreases the (Na + K)/Si ratio and increases the Ca/Si ratio of ASR products slightly. Compared with cement mortar, C–S–H in GGBS blended cement mortar has a higher (Na + K)/Si ratio, which indicates its higher alkali binding capacity. [ABSTRACT FROM AUTHOR]

The British Railway Mania of the mid-1840s led to a massive expansion of the railway network, a socially beneficial legacy that however produced a collapse of profitability and dividends. Paradoxically, the majority of this expansion was carried out by established (and hitherto successful) railways, rather than Mania promotions. Campbell and Turner (2015) see this expansion as a rational, indeed optimal, response to the Mania: they would have been worse placed with alternative strategies. This paper contends that it was established railways which began the expansion in 1843–1844, and that the high returns they generated for their shareholders depended crucially on the rights issues that financed their projected lines. This helps to explain both shareholder support for expansion, and investor enthusiasm for Mania projections. But the new lines were unprofitable: the established railways' expansionary strategy was a major managerial failure with, in the longer term, disastrous consequences for shareholders. [ABSTRACT FROM AUTHOR]

The warming climate is giving migratory birds new opportunities to extend their breeding ranges. These expansions may have a significant impact on other local bird communities. Here, we investigate the nest site selection of Mute Swan Cygnus olor, and the expanding Whooper Swan Cygnus cygnus. The study aims to assess the differences in habitat use by these two swan species in a lowland anthropogenic landscape. It examines the number of breeding pairs and the surface areas of nesting zones in different habitat types. The field procedures involved the use of unmanned aerial vehicles (UAVs) to survey and locate nests, with geotagged photographs taken to map nest locations. Our results show that Mute Swans primarily occupy oxbows, while Whooper Swans predominantly nest in pond complexes. Moreover, GLM models indicate that Mute Swans tend to choose open areas within a radius of 200 m around the nests, whereas Whooper Swans avoid built-up areas, often choosing forested sites within a radius of 500 m of their nests. These findings suggest that the expansion of the Whooper Swan population has led to changes in the breeding behaviour and habitat use of sympatric Mute Swan populations. The territorial behaviour and aggression of Whooper Swan may be driving Mute Swan away from fishpond habitats. We conclude that interactions between the two swan species are dynamic and have not yet stabilized, so this is an issue that needs to be closely monitored. Understanding these dynamics is essential for the effective conservation and management of wetland habitats in the face of ongoing climate change and shifting breeding ranges of birds. Species range shifts: climate change causes shifts in bird breeding ranges, impacting species interactions. The expanding Whooper Swan's competition with Mute Swan exemplifies this process. Selection of new habitat types: as it expands, the Whooper Swan competes with the Mute Swan for attractive breeding habitat. Differences in habitat choice: Whooper Swan most frequently chooses fishponds surrounded by forests, whereas Mute Swan nests within more open area, closer to human settlements, frequently on oxbows. [ABSTRACT FROM AUTHOR]

To promote the safe use of MgO expansive agent (MEA) in mass concrete, the influence of fineness and sintering temperature of MEA on the expansion, mechanical properties, and microstructure of fly ash-Portland cement pastes was studied. The results indicate that the agent prepared at 950 °C does not adversely affect the compressive strength of the pastes. Whereas the agent prepared at 1150 °C (MII) has a marked negative impact on the volume stability and strength of the pastes. Furthermore, incorporating MII with coarser particle size results in a larger expansion, greater strength loss, and coarser pore structure. The presence of fly ash delays the hydration of MgO, making more MgO available for the formation of Mg(OH)2 at the late age. Meanwhile, the pozzolanic reaction leads to decreased total porosity, leaving less space available for the accommodation of Mg(OH)2. Consequently, fly ash cement pastes suffer greater strength loss than plain cement pastes when the destructive expansion occurs due to the delayed hydration of MgO. [ABSTRACT FROM AUTHOR]

Professional sports leagues, like so many other organizations, seek to access international markets. The purpose of this research was to explore stakeholder perceptions of the internationalization potential of the Persian Gulf Pro League (PGPL). Data were collected via 20 in-depth interviews with football federation marketing executives, club marketing executives, and experts in internationalization and sports marketing. The data analysis was guided by the principles of grounded theory with the aid of open and axial coding. The analysis produced 39 issues affecting the internationalization of the PGPL. These were classified into five main dimensions—political, economic, managerial, legal, technical-marketing, and socio-cultural factors. [ABSTRACT FROM AUTHOR]

Consider the differential equation, $\mathop{X}\limits^{\textbf{.}}=AX+G\in C^p$ X. = AX + G ∈ C p for $X,G\in C^p$ X , G ∈ C p and $A\in C^{p\times p}$ A ∈ C p × p functions of $t\in R$ t ∈ R , where $\mathop{X}\limits^{\textbf{.}}=dX/dt$ X. = dX / dt . Its solution is built on that of its homogeneous form $\mathop{X}\limits^{\textbf{.}}=AX$ X. = AX . Consider the case when this is not known but a solution is known for $\mathop{X}\limits^{\textbf{.}}=A_0X$ X. = A 0 X , where A0 is close to A. Then, X in the first differential equation satisfies a Volterra equation that can be inverted. We gives its solution explicitly when for some small $e\in C$ e ∈ C , A and G can be expanded in powers of e. We apply this to solving $\mathop{Y}\limits^{\textbf{..}\,}+JY=g\in C^s$ Y.. + JY = g ∈ C s for $J\in C^{s\times s}$ J ∈ C s × s , and give an example needed for a series solution to the N body problem. [ABSTRACT FROM AUTHOR]

Chemical reactions can lead to the expansion of the geomaterial because of the strong precipitation of minerals in the pores of the medium. The quantity and the variability of these reactions led to the development of several chemo-mechanical models. A generic chemo-poromechanical model is proposed to predict both the material degradation induced by various concrete pathologies and the environmental multi-factor impact on the macroscopic swelling. The model is based on the coupling between reactive transport (species diffusion and chemical reactions) and poromechanics. The mineralogy and the poromechanical properties are estimated by a hydration-micromechanics model which allows to consider the material effects. The main applications are dedicated to External Sulfate Attack and Delayed Ettringite Formation of cementitious material at mesoscale. The studies highlight the ability of the model to deal with complex and various phenomena such as coupling chemical reactions with calcium leaching, sulfate sorption and ettringite precipitation, and to consider their impact on the macroscopic expansion. Results also bring out the accuracy of the chemo-poromechanical model to simulate different swelling pathologies. The characteristic crack paths induced by differential strain, material impact, and swelling at the macroscopic scale, fit with experimental observations. [ABSTRACT FROM AUTHOR]

Abstract Background Methods Results Conclusion Although resection of mesial temporal lobe lesions can be achieved with relatively low morbidity, resective surgery is not without risk. Whilst many lesions found in the anterior mesiotemporal lobe are low-grade entities, transforming and high-grade lesions have also been demonstrated. We investigate the feasibility of utilising serial quantitative volumetric imaging, to determine if a strategy of imaging surveillance can be safely employed for the management of radiologically diagnosed anterior mesial temporal low-grade tumours without a confirmed histological diagnosis.A retrospective case-note and radiology review design were utilised. The primary presenting symptomatology was recorded together with the efficacy of symptomatic control. Volumetric analysis of MRI images was performed using Brainlab software. Pre- and post-operative neuropsychological data were analysed.35 patients were identified with a radiological diagnosis of a low-grade anterior mesial temporal lobe tumour. Of these, 29% (n = 10) underwent surgical resection. For the whole cohort, the mean tumour volume at diagnosis was 6.5cm3, with a mean volumetric expansion of 1.4% per month. A significant difference was found between the volumetric expansion rate of those that underwent surgical treatment and those that did not (4.9% per month vs 0.06% per month, p < .01). Of those cases that did not undergo surgical resection, no significant difference was seen between the initial diagnostic volume and the volume at the time of their most recent interval surveillance scan (p = .97). New onset epilepsy was significantly associated with a requirement for eventual surgical tumour resection; relative risk = 6.25, 95% CI = 1.5–25.9, p = .0114.Where medical seizure control is adequate, we suggest that conservative management is feasible even in the absence of a confirmed histological diagnosis. However, in patients aged over 50 years with new onset epilepsy, a lower threshold for intervention should be considered. [ABSTRACT FROM AUTHOR]

Patterns of species' distribution and abundance are dynamic in response to changes in land cover, climate, interspecific relationships, and other factors. There are many examples of latitudinal range expansions, contractions, and shifts associated with warming climate. Global change effects are also manifested along gradients of longitude, and woody plant encroachment westward into the Great Plains might also be creating opportunities for species to expand into new areas. We used data from the North American Breeding Bird Survey (BBS) to examine the abundance of Red-bellied Woodpecker (Melanerpes carolinus) at a western edge of its distribution in Texas, Oklahoma, and Kansas. We compared BBS data from 1968–1992 to data from 1993–2018, fitting a series of generalized linear models to best explain variability in abundance. The best performing model included an interaction between time period and longitude, indicating both a change in abundance and in the distribution of abundance over time. Specifically, we found that Red-bellied Woodpecker increased in abundance near its western distributional limit over the past 5 decades, beginning at approximately – 94 degrees longitude. Los patrones de distribución y abundancia de las especies son dinámicos en respuesta a los cambios en uso del suelo, el clima, las relaciones interespecíficas y otros factores. Existen muchos ejemplos de expansiones, contracciones y desplazamientos latitudinales de área de distribución asociados al calentamiento del clima. Los efectos del cambio global también se manifiestan a lo largo de gradientes de longitud y la invasión de plantas leñosas hacia el oeste en las Great Plains también podría estar creando oportunidades para que las especies colonicen nuevas áreas. Utilizamos datos del North American Breeding Bird Survey (BBS) para examinar la abundancia del carpintero Melanerpes carolinus en el límite occidental de su distribución en Texas, Oklahoma y Kansas. Comparamos los datos de BBS de 1968–1992 con los de 1993–2018, ajustando una serie de modelos lineales generalizados para explicar mejor la variabilidad en la abundancia. El modelo con mejores resultados incluyó una interacción entre el periodo de tiempo analizado y la longitud, indicando un cambio en la abundancia y un cambio en la distribución de la abundancia a lo largo del tiempo. Específicamente, encontramos que la abundancia de este carpintero aumentó cerca de su límite de distribución occidental durante las últimas 5 décadas, comenzando aproximadamente a – 94 grados de longitud. Palabras clave: distribution, expansión, longitud. [ABSTRACT FROM AUTHOR]

We propose and implement a novel path-perturbation-based closed-form expansion for approximating option prices under a general class of models featuring stochastic volatility and jumps in both asset return and volatility. The expansion naturally employs formulas reported in the literature for pricing options under jump-diffusions with constant volatility as the leading term and provides corrections up to an arbitrary order. It offers an efficient computational tool for empirical analysis on the models through, e.g., calibration or estimation based on option data, in particular for flexible yet analytically intractable cases. [ABSTRACT FROM AUTHOR]

This study examines the implications of the 'equalisation policy' and the expansion of secondary education in South Korea in the late 1960s and early 1970s. The equalisation policy is one of the most radical school reform attempts in South Korea. A random assignment or lottery system for students was introduced for all middle schools in 1968 and all high schools in 1974, abolishing selective and competitive school-based entrance systems. This system was in operation without interruption until the early 1990s when new categories of schools were introduced as a part of South Korea's participation in the global neoliberal school reform movement. The 'second wave of equalisation' since around 2010 and subsequent measures to 're-equalise' schools draw attention to the origin of the equalisation policy and its significance in understanding the development of secondary education in South Korea. [ABSTRACT FROM AUTHOR]

In this study, we assessed the concerns of the numerous vegetable farmers whose farms are likely to be wiped out along one of Ghana's most popular roads, the Tema Motorway, if it is widened to ease the growing traffic in the rapidly urbanizing city of Accra. We employed a qualitative research design to examine the possible effects on the livelihoods of 30 farmers along the stretch. We found that the pending expansion project has brought several fears in the form of loss of livelihood and income through the possible destruction of crops and loss of land, to the farmers. We realized the idea of having no knowledge of compensation package to cushion them after they are evicted from their main source of livelihood worsens their fears. We recommend a well-structured compensation package in the form of psychological, alternative livelihood and financial support be given to them to reduce their fears. [ABSTRACT FROM AUTHOR]

As more firms adopt big data analytics to better understand their customers and differentiate their offerings from competitors, it becomes increasingly difficult to generate strategic value from isolated and unfocused ad hoc initiatives. To attain ustainable competitive advantage from big data, firms must achieve agility in combining rich data across the organization to deploy analytics that sense and respond to customers in a dynamic environment. A key challenge in achieving this agility lies in the identification, collection, and integration of data across functional silos both within and outside the organization. Because it is infeasible to systematically integrate all available data, managers need guidance in finding which data can provide valuable and actionable insights about customers. Leveraging relationship marketing theory, we develop a framework for identifying and evaluating various sources of big data in order to create a value-justified data infrastructure that enables focused and agile deployment of advanced customer analytics. Such analytics move beyond siloed transactional customer analytics approaches of the past and incorporate a variety of rich, relationship-oriented constructs to provide actionable and valuable insights. We develop a customized kernel-based learning method to take advantage of these rich constructs and instantiate the framework in a novel prototype system that accurately predicts a variety of customer behaviors in a challenging environment, demonstrating the framework's ability to drive significant value. [ABSTRACT FROM AUTHOR]

This paper develops a game-theoretic model that analyzes how a grocery store responds to the entry of a Walmart Supercenter using its store-format choice. By adopting a set of realistic assumptions, such as the cost advantage of Walmart and differentiated services of grocery stores, we find that the distance to a Walmart Supercenter is a key moderating factor in the store-format choice of grocery stores. Grocery stores would prefer to sell non-food items, but when sufficiently close to Walmart Supercenters they would specialise in food items, as consumers find it less costly to engage in two-stop shopping, making the gain from non-food items smaller. So an asymmetric equilibrium becomes feasible, wherein grocery stores carrying increasingly more non-food products and a new grocery store concept like Whole Foods and Wild Oats emphasising high-quality, organic foods can coexist. Our results yield important managerial implications. Under the specialisation strategy, the quality of its differentiated services should be sufficiently high, at least two to four times the disutility of two-stop shopping. Under the expansion strategy, grocery stores should engage in loss leadership, pricing non-food items below cost to lure large-basket consumers while earning higher margins from food items to compensate for the loss. [ABSTRACT FROM AUTHOR]

Concrete is an indispensable material in the construction industry; however, it is susceptible to many damaging mechanisms such as Alkali Aggregate Reaction (AAR). AAR initiates when alkali hydroxide in cement reacts with aggregates (fine/coarse) containing a bulk amount of silica or carbonate thereby triggering an Alkali-Silica Reaction (ASR) or Alkali Carbonate Reaction (ACR) respectively. AAR has very adverse effects on different properties of concrete including durability, stiffness, impermeability, strength, and aesthetics. AAR causes severe expansion and cracking in concrete. Although several methods can be used to mitigate AAR, the most suitable method for controlling AAR and enhancing concrete properties is the incorporation of geopolymer materials and mineral admixtures in concrete. This paper provides a comprehensive review on the mechanism, causes of AAR, and the behavior/performance of different geopolymers (a combination of an alkaline liquid with fly ash, metakaolin, and blast furnace slag) and mineral admixtures (fly ash, highly reactive metakaolin, rice husk ash, waste glass powder, ground granulated blast furnace slag, silica fume, and trass) when used to eliminate AAR and their effect on different mechanical properties of concrete. The discussion concludes that geopolymers and mineral admixtures work efficiently in the mitigation of AAR if they are used in an appropriate percentage; they not only reduce/mitigate AAR but also significantly increase the mechanical properties of concrete. [ABSTRACT FROM AUTHOR]

The conclusion of recent research on the relationship between students' school curriculum and their opportunities to enter higher education has generally been that curricular differentiation is a further dimension of social stratification, and that it has become a mechanism of effectively maintained inequality, in the sense defined by Lucas. The present analysis uses a unique series of surveys of school leavers in Scotland, covering the whole of the second half of the twentieth century, to study the relationship between curricular breadth in the senior years of secondary school and the chances of entering higher education. Breadth is found to have been long associated especially with entry to the high-status oldest universities, and also with entry to other universities that were founded before the 1990s. However, breadth of study at school and university is not a new dimension of distinction in Scotland, dating rather from the nineteenth century and earlier. Its effect has not grown with expansion, but in general has declined. The conclusion is that this curricular feature has been a mark of cultural or intellectual distinction, not straightforwardly merely a mechanism of stratification. [ABSTRACT FROM AUTHOR]

End formed components are generally used at various interconnecting elements, exhaust system of machines, fuel pipes etc. In this paper AA6061 alloy has been considered to analyse the tube end behaviour by performing the experimental and simulation studies. Simulations are performed by DEFORM-3D software. The process parameters considered are rp/r0 ratios (1.39, 1.53 and 1.67), the forming angle (α) of the punch (15°, 30° and 45°) and the thickness of tube is 2 mm. The experimental and simulation results almost following the same path. The formability values are more for the process parameters rp/r0 ratio is 1.39 and die cone angle 45°. This die is used for the further studies. The stress, strain and thickness distribution along the contact surface between tube and punch analysed and reported. The simulations revealed that the maximum stress induced at the tip of the tube and this will cause to initiate the crack. Thickness measurement was done along the tube wall from tip of the deformed tube to undeformed tube. The minimum thickness found as 1.456 mm at the tip of the tube, this is the maximum reduction of tube while forming. [ABSTRACT FROM AUTHOR]

Various writings of mixed genres, drifting between scientific treatises, mystical epiphanies, and prose fiction related to the school of "cosmism," have been explored for more than fifty years, and the interpretations range from (religious) utopia to theories of sustainable development. The author discusses the question of whether "cosmism" is exclusively "Russian," compares its general postulates with the techno-Cosmist approaches of the last ten years (including those involving fiction, such as by Eugene Thacker, and the more philosophical approaches, like that applied by Yuk Hui), and proposes clarifying how the Cosmists literally viewed the structure of the world and how they conceptualized its elements as contrasted with the interest of contemporary theorists in openness to planetary and cosmic horizons. The latter, often oriented to nuclear physics and fragmenting "reality" into stochastic agencies whose temporary couplings are formed by cutting and assembling procedures, can be reformulated from the "cosmist" perspective as gleaned in this case from the works of Valerian Murav'ev and Vladimir Vernadsky, with the aid of the categories of expansion and accomplishment. [ABSTRACT FROM AUTHOR]

The serious volume shrinkage of G-grade oil well cement during the hydration period and the initial stage of hardening will cause poor cementing quality at the first and second cementing interfaces, which will lead to annulus channeling and ultimately affect the normal production of the oil well. Therefore, we researched high-activity MgO composite expansive agent. By calcination of industrial MgO at different temperatures and then rapid cooling, we obtained MgO with different activities. We then analyzed the reactivity and microstructure of these samples and tested their effects on the volume shrinkage of cement slurry in the early stage of hydration. The experimental results showed that the activity of the sample calcined at 800°C for 1 hour then cooled rapidly is more suitable. After adding the expansive agent, the volume shrinkage rate of cement slurry can be minimized to only 0.95% after 10 hours, while the volume shrinkage rate of blank cement slurry can reach 4.02% after 10 hours. By compounding the calcined active MgO with CaO and UEA, the composite expansive agent M-AC is obtained. The evaluation results showed that M-AC expansive agent can make up for the insufficient expansion of cement after hardening, realize the volume shrinkage compensation of cement in the whole process of cementing, and improve the cementing quality. [ABSTRACT FROM AUTHOR]

The expansion of the SACEM bridge located in Villabona is a lightweight work and consists of attaching a weathering steel structure to each edge of the deck in order to extend the original width for allowing the uses for cyclist and pedestrians. The main feature of the work is its steel "V" piles, which allow the structure's span to be shortened, thus achieving a stylised appearance. The expansion of the bridge platform allows its functionality to be expanded: before it was a road-use bridge, and now it is highly appreciated by pedestrians and cyclists. A small operation has greatly improved the appearance of the bridge, improves its durability and extends its life. An ordinary structure used only by vehicles becomes a bridge appreciated by society thanks to its elegant appearance and its new cycling and pedestrian use. [ABSTRACT FROM AUTHOR]

Maxillary protraction and expansion is recommended to treat midfacial deficiency in patients with cleft lip and palate (CLP), where amount and direction of forces can change displacement and stress. This study assessed the initial displacement and stresses using Facemask and Maxgym forces with and without RME at +20∘, 0∘, and -20∘ angulation using a finite element (FE) model of unilateral cleft lip and palate (UCCLP). The Initial displacement and stress were more for protraction with expansion as compared to only protraction. Asymmetric displacement was observed with more on cleft than on noncleft side and more on dental than skeletal structures. Palatal plane rotated less upward, increased arch width and decreased arch length was observed with protraction with expansion. [ABSTRACT FROM AUTHOR]

In this study, mixed fuel droplets of ethyl alcohol and biodiesel with different volumes or ratios were prepared and the related expansion, injection and micro-explosion phenomena were investigated. During the tests, a mixed-fuel droplet was hung on a high-temperature-resistant Cr-Ni wire, which was transported to the preheating piston for heating and then was ignited automatically. Micro-needles and an infusion set also were employed to prepare mixed droplets with identical ratios but different volumes. Using a single-lens-reflex (SLR) camera, colour videos that captured the combustion process of the mixed droplets were taken and were processed into colour images using Adobe Premiere Pro CC. The colour image series were analysed to determine the ignition delay time, the burnout time and the flame characteristics during combustion of mixed droplets with different ratios. Instantaneous grey images were obtained by means of high-speed photography during combustion of the mixed droplets with different volumes and different ratios, and of droplets of E40 (in which the volume ratio of ethyl alcohol was 40%). Using Image pro plus and Origin software, the variation of normalised mean droplet diameter with time over the whole combustion cycle was calculated and the underlying reasons for various combustion phenomena were analysed. [ABSTRACT FROM AUTHOR]

In this work, a quasi-one-dimensional ZND model of detonation considering the expansion process perpendicular to the detonation propagation direction is extended to the rotating detonation engine (RDE) to investigate the influence of expansion on the detonation waves in RDEs. This model is first used in more general cases of one-dimensional detonation waves, coupled with the one- and two-step kinetic models for stoichiometric hydrogen-air mixtures. The expansion has an effect on reducing the detonation propagation speed and can be attributed to two factors: the extra work during expansion and the lost heat released behind the sonic point. The one that plays the more important role depends on the kinetic model. Finally, a set of numerical simulations of RDEs are performed for comparison with the theoretical model. The results show that the expansion process in RDEs reduces the speed of the detonation wave by approximately 5%, which is an important factor for the detonation velocity deficit in two-dimensional simulations. [ABSTRACT FROM AUTHOR]

In this article, we integrate the attention-based view of the firm and the organizational ambidexterity literature to develop a perspective on the effects of unbalanced attention to both domestic and foreign expansion. We utilize the case of British supermarket Tesco's expansions in the UK and USA to demonstrate divestment as an unintended outcome of unbalanced attention to both domestic and foreign markets. We demonstrate how emerging-market multinationals could learn from historical international expansion strategic failures by developed-country multinationals. [ABSTRACT FROM AUTHOR]

This study uses quarterly EU Labour Force Survey data for 30 countries over the period 2000 to 2016 to examine the relationship between changes in the composition of educational attainment and overeducation rates among new labour market entrants holding post-secondary and tertiary qualifications. We find that tertiary education expanded rapidly across our sample, while the proportion of young people with lower levels of education fell gradually throughout the period. Despite the significant increases in the percentage of young people educated to tertiary level, overeducation among new tertiary graduates fell. The descriptive evidence also suggests that some of the greatest declines in overeducation of young tertiary graduates occurred in the countries experiencing the most significant expansion in tertiary education. Overeducation rates among young graduates with upper-secondary and postsecondary (non-tertiary) education were lower in magnitude than overeducation of tertiary graduates and declined slightly over the period. Our GMM results confirm the negative relationship between educational expansion and overeducation for both tertiary and post-secondary graduates, and reveal a number of other factors potentially explaining cross-country variation in youth overeducation rates. [ABSTRACT FROM AUTHOR]

Short waste fibers are used to suppress the expansion and improve the tensile strength of cement-stabilized marine clay (CMC). The fiber-reinforced mechanism and characteristics are revealed by experimental and numerical methods. First, the curing effect of the CMC when adding a composite curing agent is observed by scanning electronic microscopy, as is the contact surface between the fiber and the matrix. Then, the expansion rate and the tensile strength of fiber-reinforced cement-stabilized marine clay (FCMC) are illustrated by an expansion experiment and a direct tensile experiment, respectively. The results show that the sample with the cement content of 0.1% and the fiber length of 10 mm is the best in terms of strength enhancement and expansion inhibition. Finally, the mechanism of fiber reinforcement is discussed following a single fiber pullout experiment and some comprehensive explanations are proposed to verify the results of the tensile experiment. A numerical simulation of a single fiber pullout from a matrix is established by using a cohesive contact model. The comparison between the numerical results and the experimental results shows that the two models can be in good agreement, indicating that the calculation model of the interaction between the fiber and the matrix is realistic. [ABSTRACT FROM AUTHOR]

An explicit representation of the Green's function of the Dirichlet problem for the biharmonic equation in the unit ball is given. Expansion of the constructed Green's function in the complete system of homogeneous harmonic polynomials that are orthogonal on the unit sphere is obtained. Solution of the homogeneous Dirichlet problem with a simple right-hand side of the biharmonic equation is found. [ABSTRACT FROM AUTHOR]

pH-sensitive water and oil dual-absorption material (WODAM) has been successfully synthesized through microemulsion polymerization. Firstly, microemulsions prepared with monomers were analyzed by pseudo-ternary phase diagram. In addition, conductivities of microemulsions were tested to identify microemulsion types. Meanwhile, the factors that affected microemulsion types were analyzed. Then WODAMs were prepared, and the chemical structure was characterized using Fourier transform infrared (FTIR) spectroscopy. Liquid absorption tests indicated that both monomer ratio and microstructure of WODAMs had influences on their water absorption rate (WAR) and oil absorption rate (OAR). In addition, pH sensitivity tests showed that WODAM absorbed much water in neutral and weak alkaline solutions, but little water in strong alkaline solutions. What's more, liquid absorption tests in cement slurry filtrate (CSF) showed that WODAM was applied to oil well cement. This paper prepared a new self-healing agent, and is of great significance to realize self-healing cement in complex downhole condition. [ABSTRACT FROM AUTHOR]

The mixtures of blue cornmeal and orange bagasse were processed in a single screw laboratory extruder. We used an experimental design, central composite rotatable, where the factors were as follows: extruder die temperature (153-187°C), feed moisture (146.4-213.6 g/kg), and orange bagasse concentration (32.7-167.3 g/kg). The results were analyzed by surface methodology response to evaluate the effect of these variables on the expansion index, bulk density, penetration force, specific mechanical energy, water absorption, and water solubility index. All independent variables had an effect on the evaluated responses (p ≤ 0.05). The highest expansion index was obtained at a feed moisture content of 146.4 g/kg, orange bagasse (100 g/kg), and 170°C at the exit die. The use of blue maize and orange bagasse can be an alternative to increase the added value of these two raw materials, and to improve the nutritional quality of extruded products ready to eat. [ABSTRACT FROM AUTHOR]

This article examines how frontier zone expansion and the migration of Asian professionals reinforced each other in complex and indirect ways. It focuses on Hawaii as a microcosm of transnationalism in medicine, analyzing its role as a host for licensed physicians from Japan, the United States, and other countries from 1868 to 1924. Looking beyond the context of a single East Asian country and East Asia as a region, or the East-West dichotomy, this study places all involved territories within the broader trans-Pacific arena to convey the sense of interconnectivity that human resources brought about between all the involved territories. The confluence of (geo)politics in Japan, East Asia, the Pacific, the United States, and the rest of the world molded intellectual migration in medicine from Japan to Hawaii, migration that served as an economically viable, diplomatically peaceful, and socially benign form of expansion. [ABSTRACT FROM AUTHOR]

This article tests effectively maintained inequality theory against the case of China. Employing Chinese College Student Survey data from 2012, the study elaborates on the rationale and causes behind the expansion of higher education over the last two decades and the impact this has had on the system. Rather than empowering disadvantaged students, the findings show that the expansion of Chinese higher education fails to reduce the inequity in China, in particular in providing low socio-economic status students access to elite Chinese universities and obtaining good positions in the job market. [ABSTRACT FROM AUTHOR]

In this paper, the higher order asymptotic expansion of the moments of extreme from generalized Maxwell distribution is gained, by which one establishes the rate of convergence of the moment of the normalized partialmaximum to the moment of the associated Gumbel extreme value distribution. [ABSTRACT FROM AUTHOR]

Internal cured concrete (ICC) has been recently used in the local and international construction markets. ICC contains surplus amount of water to compensate the shrinkage of the mix and the volumetric changes which result in early-age cracking of concrete. Concrete cracking is a direct result of the shrinkage of the water-cement paste during early stages of the hydration process and continues for a significant amount of time during the life span of the concrete section. Early-stage shrinkage, prior to the concrete hardening, is associated with volumetric changes, until final setting is achieved. Afterward, the reduction in cement paste particle size results in increased voids within the concrete structure. These voids result in increased permeability, additional sulfate and chloride attacks on steel reinforcement, and internal tensile stresses in concrete, which result in significant cracking. ICC uses the additional water added to the mix in counteracting the reduced volume of the concrete. Several techniques are used for internal curing (IC). In this research, water-saturated lightweight aggregates (LWAs) are used in partial replacement of normal weight aggregate as a source of additional water. LWA is submerged in water prior to concrete mixing to absorb a significant amount of water, which is stored within the LWA particles. Once added to the mix, the water is gradually desorbed and compensates the water losses during hydration. Hence, it counteracts the shrinkage induced. Different ICC mixes are developed in this research using two different sizes of LWA, and supplementary binding materials are used to improve compressive strength. ICC compressive strength and reduced shrinkage attained are presented. ICC mixes developed in this research can be successfully used in pouring highway segments and bridge decks with lower cracks and reduced life cycle cost due to reduced maintenance. [ABSTRACT FROM AUTHOR]

To determine the effects of feed processing method (extrusion or expansion followed by compression pelleting) on feed physicochemical characteristics, fecal stability, water quality, and growth performance in rainbow trout, three types of feed pellets (expanded sinking [EpS], extruded sinking [ExS], extruded floating [ExF]) were prepared, analyzed, and fed to juvenile rainbow trout (initial weight = 285.8 ± 15.2 g) at three feeding rates based on feeding rate curves developed at Snake River Farm (Buhl, Idaho, USA) (median rates [%BW] for feeding rate 1: 0.85; feeding rate 2: 0.95; feeding rate 3: 1.05) for 124 days. Results showed that all feeds had similar chemical composition, but the degree of starch gelatinization (as % of starch) was significantly higher in ExS (90.01 ± 0.26) and ExF (84.82 ± 0.63) than in the EpS (9.09 ± 0.41) feed, which led to extruded feeds having much higher water stability, fecal durability, and lower phosphorus discharge. The ExF feed produced better growth (% increase; 154.4 ± 18.5) and feed conversion (1.06 ± 0.06) compared to EpS (126.3 ± 12.4 and 1.26 ± 0.14) and ExS (121.7 ± 7.8 and 1.22 ± 0.04) in rainbow trout. Growth (% increase) improved as feeding rate increased (feeding rate 1: 125.6 ± 10.3; feeding rate 2: 140.8 ± 16.0), but further improvements were not observed at the highest feeding rate (feeding rate 3: 135.9 ± 22.8). The present study is the first to show that the extrusion process not only produces pellets having better quality than the expansion-compressed pelleting method but also improves fecal size and durability in water, and therefore, use of extruded feeds has the potential to improve waste collection and removal and reduce contribution to pollution in effluent. [ABSTRACT FROM AUTHOR]

When studying a complex research phenomenon, a mixed methods design allows to answer a broader set of research questions and to tap into different aspects of this phenomenon, compared to a monomethod design. This paper reports on how a sequential equal status design (QUAN → QUAL) was used to examine students’ reasoning processes when solving probability problems. A select clustered sampling resulted in the inclusion of 168 high school students in a first, quantitative phase, in which a questionnaire was used to assess how they solved probability problems. This questionnaire included probability items that were based on the outcome orientation, the representativeness misconception, and the equiprobability bias. In a second, qualitative phase, 18 students who were purposefully sampled from the first research phase were interviewed in order to conduct an in-depth study of their probabilistic reasoning processes. In this paper, we illustrate and discuss how several mixed methods research purposes were realized throughout our study:development,expansion, andinitiation. [ABSTRACT FROM AUTHOR]

Many barriers must be overcome when entering the base-of-the-pyramid (BoP) market. Firms facing these barriers need to innovate new business models and reinvent existing ones to suit the BoP context. While previous literature has focused on the innovations of particular components of business models in BoP markets, we investigate the reconfigurations in the business model components that underpin the successful business model innovations. This study is based on multiple case studies in the water sector that we carried out in several different countries. Our findings suggest five business model innovations: (a) design, (b) renewal, (c) expansion, (d) diversification and (e) replication. Each business model innovation is a specific response to the barriers met in the BoP market and requires consistent configuration between its various components (i.e. value proposition, value creation and profit equation). These findings add, in two important aspects, to the academic realm of the business model domain: by contributing to the debate of business models in BoP markets and by advancing the configurational view of business models. [ABSTRACT FROM AUTHOR]

Using as a starting point in the recent work of Mountford-Zimdars et al., the authors analyse attitudes towards expanding higher education (HE) opportunities in the UK. The authors propose that the approach of Mountford-Zimdars et al.is flawed not only in its adoption of a multivariate logistic regression but also in its interpretation of results. The authors make a number of adaptations, chief among them being the use of an ordered probit approach and the addition of a time dimension to test for changes in attitudes between 2000 and 2010. The authors find that attitudes towards HE expansion have intensified during the decade 2000–2010, but the authors uncover no evidence that this is due to graduates wanting to ‘pull up the ladder’, as suggested by Mountford-Zimdars et al. The authors argue that evidence of a widespread desire to reduce access to HE can most likely be explained by social congestion theory, internal institutional disaffection and rising tuition fees. [ABSTRACT FROM PUBLISHER]

The jumbo squid (Dosidicus gigas) is one of the species of commercial interest as a source of protein and has potential for the development of ready to eat food products including expanded snacks by extrusion (SEE). The objective of this research was to determine the effect of the conditions of the extrusion process on the physicochemical properties of SEE made with 40% squid flour (HC) and 60% of potato (HP)/maize (HM) flour mixes in ratios (w/w) of 10/50, 30/30 and 50/10. The best values of expansion rate (2.87), bulk density (0.14 g/cm3), firmness (7.22 N), water solubility index (27.76%) and water absorption index (5.64 g H20/g sample) were obtained with the mixture of higher content of potato flour. It is concluded that it is possible to produce ready to eat expanded snacks from squid meal rich in protein (>40%) and good physicochemical properties. [ABSTRACT FROM AUTHOR]

We empirically examine whether firms make investment decisions in anticipation of recessions and subsequently perform better. Using a large quarterly dataset of fixed asset investments for U.S. firms during 1984–2012, we show that not all firms efficiently adjust their investment decisions in anticipation of a recession. However, we find that pre-acting firms that properly adjust their investment decisions (i.e., underinvest) before a recession outperform re-acting firms that fail to make proper investment decisions (i.e., overinvest) before a recession in subsequent returns on assets, returns on investments, and market-adjusted return measures. [ABSTRACT FROM AUTHOR]

In this article we analyze the effectiveness of fiscal policy—for a group of four Central and Eastern European countries. The recent literature shows that fiscal multipliers in the developed economies are higher during recession than expansion. So far, similar empirical analyses have been lacking for CEE countries. The results presented in this article show that fiscal multipliers in CEE countries differ with respect to the phase of the business cycle. Based on the SVAR methodology in which we allow for deterministic regime switching, we show that the government spending multipliers are significantly higher when the output gap is negative. [ABSTRACT FROM AUTHOR]

Copyright of Regional Studies is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Regional Studies is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The aim of this study was to identify suitable starch sources that can improve the structural integrity of plant protein-based extruded feeds, specifically aquatic feeds. Extrusion trials were performed, using a single-screw extruder. Extruder temperature, screw speed, and moisture content were varied in a factorial design with a replicated central composite point. The effects of these variables on functional and structural properties of the extrudates were evaluated. Temperature had the dominant effect on all properties. Increasing extruder temperature resulted in notable increases in onset temperature of gelatinization and glass transition temperature of all extrudates. The lowest water absorption, alkaline viscosity, and the highest water solubility, in addition to the lowest Rapid Visco Analyzer profile were found for corn starch extrudates. The lowest thermal stability was observed for the potato extrudate. It is expected that cassava and potato starches can contribute better in the formation of a cohesive structure and the generation of more expanded extrudates, specifically in the production of aquafeed. The higher enthalpy transition of corn extrudates indicated the higher thermal stability of corn starch which can lead in production of more durable aquafeed extrudates. [ABSTRACT FROM PUBLISHER]

In this paper, we explore the possible contributions of empirical moral philosophy to professional ethics in teacher education. We argue that it is both possible and desirable to connect knowledge of how teachers empirically do and understand professional ethics with normative theories of teachers’ professional ethics. Our argument is made in dialogue with the moral philosophy of Charles Taylor and the emerging tradition of ‘empirical ethics’ in psychiatry. We also draw on empirical data from a larger empirical project on teachers’ professional ethics in Norway. Our main contribution is the development of a method for empirical professional ethics that involves three steps: articulation, disturbance and expansion. [ABSTRACT FROM AUTHOR]

Effects of grinding and hydro-thermal treatment of feed on growth performance, slaughter traits, nutrient digestibility, stomach content and stomach health were examined by using 96 crossbred fattening pigs. Pigs were fed a grain-soybean meal-based diet processed by various technical treatments. Feeding groups differed in particle size after grinding (finely vs. coarsely ground feed) and hydro-thermal treatment (without hydro-thermal treatment, pelleting, expanding, expanding and pelleting). Fine grinding and hydro-thermal treatment showed significant improvements on the digestibility of crude nutrients and content of metabolisable energy. Hydro-thermal treatment influenced average daily gain (ADG) and average daily feed intake (DFI) significantly. Finely ground pelleted feed without expanding enhanced performances by increasing ADG and decreasing feed-to-gain ratio (FGR) of fattening pigs. Coarsely ground feed without hydro-thermal treatment resulted in the highest ADG and DFI, however also in the highest FGR. Expanded feed decreased DFI and ADG. Slaughter traits were not affected by treatments. Coarsely ground feed without hydro-thermal treatment had protective effects on the health of gastricpars nonglandularis,however, pelleting increased gastric lesions. Hydro-thermal treatment, especially expanding, resulted in clumping of stomach content which possibly induced satiety by slower ingesta passage rate and thus decreased feed intake. Pigs fed pelleted feed showed less pronounced development of clumps in stomach content compared with expanded feed. [ABSTRACT FROM AUTHOR]

Drawing on data from South Korea, this paper attempts to assess three dominant views on the evolution of morbidity and mortality of the elderly: expansion of morbidity, compression of morbidity, and dynamic equilibrium. The expansion of morbidity perspective argues that elongated life expectancy would comprise of, in large part, disabled life expectancy. The compression of morbidity theory suggests that increases in active life expectancy correspond to increases in total life expectancy. The dynamic equilibrium theory posits that, though overall levels of morbidity would rise, the prevalence of severe disability would decrease. The study is based on mortality data from Life Tables for Korea and the morbidity data from five nationally representative cross-sectional surveys conducted in 1994, 1998, 2004, 2008, and 2011. Sullivan's method is used to compute the active, mildly disabled, and severely disabled life expectancies. Results reveal that the total life expectancy of elderly Koreans has markedly increased, and this has been accompanied by an impressive extension of active life expectancy. In addition, results show negligible declines in the mildly disabled life expectancy but rapid drops in the severely disabled life expectancy. Collectively, these observations strongly support the compression hypothesis, and provide partial support for a dynamic equilibrium. [ABSTRACT FROM AUTHOR]

This article examines the mid-1840s expansion of the British railway network, which was associated with a large deterioration in shareholder value. Using a counterfactual approach and new data on railway competition, we argue that the expansion of the railway companies, and their subsequent decline in financial performance, was not due to managerial failure. Rather, the promotion of new routes by established railways and mergers with other companies was part of a managerial strategy to maintain incumbent positions, and may have been preferable to not expanding whilst their competitors did. [ABSTRACT FROM AUTHOR]