Methotrexate resistance and gene amplification in choriocarcinoma cells in vitro.

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Windage measurements in a rotor stator cavity with rotor mounted protrusions and bolts

This paper reports an experimental investigation of the windage associated with enclosed rotor-stator systems with superposed throughflow, as commonly found in gas turbine engines. The term windage is often used to describe the viscous heating that arises from the interaction of surfaces and fluids in rotating disc systems. Since the presence of circumferentially discreet geometric features strongly alters the magnitude of Windage measured, the physical mechanisms collectively referred to as windage in this paper are separately described as part of the discussion of results. Tests have been carried out to measure windage directly in the form of shaft torque and also rotor surface temperature. Non-dimensional flow parameters are used to expand the relevance of the data obtained, which encompasses the ranges 0.17 x 107 ≤ Reφ ≤ 1.68 x 107and 0.24 x 105 ≤ Cw ≤ 1.06 x 105 which corresponds to 0.058 ≤ λT ≤ 0.631. Data has been obtained for smooth disc geometry and also with rotor mounted protrusions of N = 3, 9 and 18; D = 10 mm, 13 mm and 16 mm diameter; H = 11 mm, high, hexagonal bolt shaped protrusions. Bi-hexagonal (twelve sided) bolts of D = 13 mm effective diameter, and height, H = 11mm, were also tested with conditions closely matched to the 13 mm hexagonal bolts. Finally, tests with 10 mm diameter, 6 mm deep, pockets were also carried out. Over the range of conditions and geometries tested, increasing the number of bolts increases the moment coefficient and windage heating. At low values of turbulent flow parameter, λT, which correspond to rotational speeds between 8000 and 10000 rev/min, increasing the diameter of the bolts shows a clear trend for both increased windage torque and average disc temperature rise. For these conditions, there also appears to be a clear reduction in windage and temperature rise with the bi-hexagonal shaped bolts compared to the equivalent diameter hexagonal bolt form. Variation in the moment coefficient with the number and diameter of bolts is attributed to variations in form drag between the different configurations. The introduction of the recesses onto the disc has very little effect on either windage heating or moment coefficient; this is attributed to the component of windage mechanism in operation and also the relatively small size in comparison to the protrusions studied here. This work contributes to the understanding of windage in gas turbines by introducing new low uncertainty data obtained at engine representative conditions and as such is of benefit to those involved with the design of internal air systems and disc fixture

Durability of rubber components under multiaxial cyclic stresses

An accurate understanding of the fatigue behaviour of structural components through their working life, is a key factor for a light-weight and optimal design. Fatigue life has to take into consideration a series of parameters spacing from material properties, to working condition to the nature of the cyclic loads. This work consist in the development of a technique able to determine fatigue life of rubber components as well as the location and direction of the cracks. An hyper-elastic, third-order, five-parameter, phenomenological material model has been selected and multiple components have been simulated under variable cyclic multi-axial loading.Several fatigue indicators and damage accumulation models have been taken into account. Eventually Cauchy rotated stresses have been chosen as fatigue indicator, coupled with Palgrem-Miner damage accumulation rule calculated in different spacial directions using critical-plane method. The Cauchy rotated stresses have been selected in order to be able to implement Haigh diagram data from existing literature. Furthermore the use of this tensor enables the determination of the location and orientation of critical planes referred to the un-deformed configuration. A custom equivalent stress method has been implemented in order to take into account mean stress sensitivity deriving from phenomena like strain induced crystallization. The developed method has been tested against literature as well as experimental data in order the evaluate its quality. Correct calculation of the co-rotated Cauchy tensor has been verified against a uni-axially loaded specimen subjected to a rotation in the reference system. A diabolo specimen has been simulated under torsional loading in order to verify the correct location and orientation of cracks. Correct interpolation of multi-axial stress states deriving from multiple external loads have been verified against results from a FEM solver. Lastly a component from literature has been tested using different load signals, and the data from fatigue life, crack location and crack orientation have been gathered. The procedure proved to be successful in the prediction of the location and orientation of cracks referred to the un-deformed configuration. Furthermore a precise fatigue life estimation of components under different load signals has been achieved. The procedure is highly customizable depending on fatigue and material properties of the specimen analysed. This procedure has proven to be a successful predictor tool for fatigue life estimation of multi-axially, cyclic loaded rubber components

The effectiveness of parenting programmes: a review of Campbell reviews

Parenting practices predict important outcomes for children, and parenting programmes are potentially effective means of supporting parents to promote optimal parenting for pre-adolescent children. The aim of this review was to evaluate the effectiveness of parenting programmes by summarising findings of relevant systematic reviews published in the Campbell Library. Six Campbell systematic reviews evaluated the effectiveness of a range of parenting programmes in the primary and secondary prevention of behavioural problems (among children aged 0 – 3 years), early onset conduct disorder (among children aged 3 – 12 years), outcomes for parents and children with ADHD, outcomes for particular groups of parents and children (i.e., with intellectual disabilities and teenagers), and the psychosocial functioning of parents. The findings of these reviews show that parenting programmes can be effective in improving the emotional and behavioural adjustment of children in the first 12 years of life, in addition to enhancing the psychosocial wellbeing of their parents. The findings also suggest that further research is needed to assess effectiveness of programmes for specific subgroups of parents (e.g., fathers, teenagers, parents with intellectual disabilities) and to assess the long-term effectiveness of parenting programmes

English word-formation: suffix competition in nominalization

openAfter giving a brief overview of English morphology and word formation, the first chapter provides an examination of derived state/event/result nouns formed by the use of suffixes, with particular attention to the morpho-syntactic characteristics of the verbal base they attach to. In some cases more than one suffix is used to derive the same or similar meaning, therefore I will analyze suffix competition in the formation of nouns and its semantic consequences, as well as providing notions about suffixes characteristics. In the second chapter I will investigate in detail the concept of polymorphism, furnishing a brief review of theoretical approaches to competition. The last part will take a closer look to competition between derivational suffixes -ation and -ment, taking in examination some particular cases of verbs that take both suffixes, both from a synchronic and dyachronic prospective.After giving a brief overview of English morphology and word formation, the first chapter provides an examination of derived state/event/result nouns formed by the use of suffixes, with particular attention to the morpho-syntactic characteristics of the verbal base they attach to. In some cases more than one suffix is used to derive the same or similar meaning, therefore I will analyze suffix competition in the formation of nouns and its semantic consequences, as well as providing notions about suffixes characteristics. In the second chapter I will investigate in detail the concept of polymorphism, furnishing a brief review of theoretical approaches to competition. The last part will take a closer look to competition between derivational suffixes -ation and -ment, taking in examination some particular cases of verbs that take both suffixes, both from a synchronic and dyachronic prospective

Outgroup homogeneity effect in perception: An exploration with Ebbinghaus illusion

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/86925/1/j.1467-839X.2010.01339.x.pd

Contrasts : Differences and similarities in choral settings of Christina Rossetti\u27s poems

Choral music is a unique art form because it combines text with music. This juxtaposition allows the two elements to enhance each other, working together to create a clearer product. Composers of choral music must make carefully informed decisions when selecting a text and deciding how to set it to music. The characteristics of the text can have observable effects on the choices a composer makes in their setting. These effects are the subject of this thesis. I wanted to study musical settings of one poet to determine whether certain characteristics of the poetry had noticeable effects when set by various composers. I studied a representative selection of choral pieces setting the poetry of Christina Rossetti in order to determine the relationship between the text and the music. I began by reviewing dozens of choral settings of Rossetti’s poems and selecting a portion for closer analysis. I chose multiple poems set by the same composer as well as multiple settings of the same poem by different composers to identify similarities and differences between the settings. I conducted a detailed musical analysis of each piece, observing things like style, texture, harmony, form, rhythm, and character. Next, I organized a small ensemble of singers and led rehearsals of the selected music, using my analysis to inform the rehearsal process. Finally, this project culminated in a recorded performance of the selected pieces, accompanied by my commentary on the results of my analysis

Samuel Hopkins Adams, his Novel, Revelry, and the Reputation of Warren G. Harding

In November 1926, Samuel Hopkins Adams\u27s novel of Washington politics, Revelry, appeared. Since its central character is an American President easily identifiable as the late Warren G. Harding, it created a great stir. Adams\u27s characterization of Harding was sympathetic, but also uncomplimentary, suggesting several negative personal attributes. A controversy over the appropriateness of Adams\u27s behavior ensued. In the press, Adams was either lauded for telling the truth about Harding or condemned for his bad taste in maligning the President, who died in 1923. Papers of Samuel Hopkins Adams preserved in the Bird Library of Syracuse University, reveal that the author and his publisher made careful plans to launch the book and relished the resulting controversy. The papers illuminate the processes involved in a book\u27s production, publication, and promotion