bluuebunny/crossref_metadata_2025_split huggingface dataset:
Heterologous up-regulation of the histamine H1 receptor by M3 muscarinic receptor-mediated activation of H1-receptor gene transcription
Authors: Miyoshi Katsuhiro , Kawakami Nozomi , Das Asish Kumar , Fujimoto Katsumi , Horio Shuhei , Fukui Hiroyuki 
Published: July 2007

AbstractHistamine H1 receptor (H1R) level varies under various pathological conditions, and these changes may be responsible for some pathogenesis, such as allergic rhinitis. Previously, we showed that H1R was heterologously down-regulated (through degradation of H1R) by prolonged stimulation with muscarinic M3 receptor (M3R) in Chinese hamster ovary (CHO) cells stably expressing H1R and M3R. However, this cell was inadequate for studying the effects on H1R gene regulation, because the cell expresses H1R, which is under the control of the SV40 promoter. Therefore, in this study, we have investigated the possible role of M3R stimulation in the H1R gene transcription and H1R mRNA stability by using U373 astrocytoma cells that express endogenous H1R and transfected M3R. Stimulation of M3R significantly increased H1R promoter activity and H1R mRNA level without alteration in H1R mRNA stability. The H1R level was also up-regulated by M3R activation (150% of control by treatment with carbachol for 24 h). These M3R-mediated events were almost completely blocked by the protein kinase C (PKC) inhibitor, Ro 31–8220, suggesting the involvement of PKC. These results indicated that M3R was involved in the up-regulation of H1R by activating H1R gene transcription through a PKC-dependent process.
Stresses in torispherical drumheads: A critical evaluation
Authors: Fessler H , Stanley P 
Published: July 2007

An empirical equation is used to compare the results of the authors' extensive photoelastic study with stress concentration factors and other forms of head shape factor obtained from independent experimental and analytical work and from some codes of practice. Important differences are shown between the stress distributions in a number of shallow, thin models and a prototype and some analytical solutions. The variations of elastic stress concentration factor with wall thickness and with knuckle radius obtained from the photoelastic work are compared with other versions. The simplifications implicit in the recommendations of codes of practice are outlined and some recommendations are made for further work.
An investigation of the fatigue life of typical aircraft gas turbine compressor discs
Authors: Owen M. J. , Dudley B. R. 
Published: July 2007

The numerous discs which are incorporated in gas turbine rotors are subjected to high level stresses at full engine speed. Each time the engine is operated and run up to maximum speed one cycle of stress is applied to each disc. In the course of time there exists the possibility of a fatigue failure. The life of a component cannot be predicted accurately from the properties of laboratory specimens of the material because of the more complicated stress pattern and the number of manufacturing variables which affect the fatigue properties. A special testing machine was built to subject compressor discs to cyclic loading at the blade fastenings whilst the disc remained stationary. Stress distributions for a typical disc were calculated for rotating and non-rotating conditions. Strain gauges were used to measure the stresses under the non-rotating conditions of the testing machine. Comparisons of theoretical and experimental results were made. It was concluded that by applying loads of sufficient magnitude at the rim it was possible to produce stresses at the bore of the same magnitude as those produced under rotating conditions and that the method of loading produced a reasonable simulation of the stress distribution in the central part of the disc. Under non-rotating conditions with these high loads the tangential stresses in the outer part of the disc were about 30 per cent higher and the radial stresses about 60 per cent higher than under rotating conditions. It was found necessary to make modifications to the discs for the fatigue tests. When loaded through the standard pinhole blade fastening, the discs failed from the pinholes because of the increased nominal stress in the rim and the high local load. By cutting off most of the rim and using grips instead of the standard pin fastening it was possible to obtain failures in the diaphragm of the discs. Although the individual discs failed in different modes with fractures arising from several sources the lives of all the discs tested lay between 34 000 and 130 000 cycles. These lives were satisfactory compared with service requirements. Typical aircraft engines accumulate from 1000 to 4000 flight cycles per year according to service conditions.
Radial pressure exerted by piston rings
Authors: Bin Chik Ahmad. , Fessler H 
Published: July 2007

The local pressures exerted by 15 in diameter rings closed to a circular shape by 36 point loads were measured with strain gauges. Departures from the theoretical open shape and from a circle when closed by tangential end forces, which simulated uniform pressure, did not predict the variations in local pressure. Double integration of pressures around the rings led to the open shape defects of the same order of magnitude as the measured values. Variations in local pressure exerted by actual piston rings can only be determined by direct, multipoint measurement.
Parallelogrammic elements in the solution of rhombic cantilever plate problems
Authors: Dawe D. J. 
Published: July 2007

The finite element method is applied to the calculation of the deflection under a uniformly distributed load and the natural frequencies of the rhombic cantilever plate. This has required the derivation of stiffness and inertia matrices for a plate element of parallelogrammic planform. Although, in common with the work of past investigators, the accuracy of the results decreases with increase in skew angle it is shown that the method is adequate for angles up to about 45°.
Elastic-plastic strain distributions in short-link chain under load
Authors: Hawkes I , Foley J H 
Published: July 2007

The strain distribution in short-link chain under load has been examined by a photoelastic-coating technique. It has been shown that at loads up to and just beyond the elastic limit the position of maximum strain occurs at a junction of an intrados and a straight side of the link. Beyond the elastic limit, however, changes in link geometry cause the position of maximum strain to move to the link crown. These results confirm observations of the positions of the fractures in fatigue and static tensile tests to failure but the stress concentration factors calculated from the results disagree with theoretical predictions. This anomaly is explained by assuming that the area of contact between adjacent links effects a spreading of the load, whereas the theoretical treatment assumes point contact between adjacent links.
Computation of finite strains from moire displacement patterns
Authors: Bossaert W , Dechaene R , Vinckier A 
Published: July 2007

A new and accurate method is described for deriving finite strains from moiré displacement patterns. The components u and v of the displacements at the mesh points of a Lagrangian co-ordinate network are estimated from the moiré fringes. In the neighbourhood of a point, where the strains are to be calculated, two algebraic functions are determined, approximating as closely as possible to the two sets of estimated u and v values. The strains are then calculated from the partial derivatives of these two functions. The procedure is repeated for all points at which the strains are required. When this procedure is applied to a great number of points the use of a computer becomes a practical necessity. Once the formulae have been programmed, the operator has only to estimate the u and v values at the mesh points of the co-ordinate network and to feed this set of numbers to the computer. This new method thus allows a considerable gain in time and brings about an improvement in accuracy compared with other methods.
Effect of multiaxial stresses on the fracture strength of silicon carbide
Authors: Priddle E K 
Published: July 2007

This work describes the fracture behaviour of silicon-carbide tubular specimens under multi-axial stresses at room temperature. A method of obtaining combinations of stresses in the form of torsion, hoop, axial tension, and compression is described and failure envelopes for silicon carbide are included from the data obtained. Failure theories are reviewed and the results from the work show that the available theories are inadequate to describe both the tension-tension and tension-compression quadrants. For practical purposes a straight-line relation can be used joining axial and hoop tensile strengths and the axial compression strength.
In-plane bending of single, unreinforced mitred pipe bends
Authors: Kitching R , Thompson W J 
Published: July 2007

Measurements of strain, transverse deflection, and change of radius have been taken on single unreinforced pipe bends subjected to in-plane bending moments. Specimens having three different mitre angles for each of two sizes of pipe have been used. Observations were made with different combinations of leg lengths for each specimen. Stresses and flexibilities are compared with those calculated by the formulae given in the A.S.A. Piping Code B.31.1 and the concept of equivalent smooth bend is examined. Alternative methods of assessment are considered and improved methods are suggested.
Finite-element stress analysis of a non-linear problem: A connecting-road eye loaded by means of a pin
Authors: White D J , Enderby L R 
Published: July 2007

The stress analysis of a connecting rod under a tensile load represents a non-linear problem, since the distribution of the forces, acting between the eye of the rod and the pin, changes as the loading proceeds. This is due to the tendency of the eye to deform, thus wrapping itself around the pin as the clearance between the parts is reduced. In consequence, the stress pattern in the eye also changes. Such a problem has been solved with a linear elastic finite-element computer programme. A connecting-rod eye was idealized as a plane-stress problem and special elements were introduced to connect the pin and rod together. These elements were assigned stiffnesses which were changed in a prescribed manner after each iteration until compatibility of forces and displacements, with due allowance for initial clearances, was obtained at each connecting point. Although eight iterations were required to achieve the correct displacements, it was found that the circumferential stresses did not change appreciably after the first few iterations. Good agreement was found between the calculated stresses and those measured in a laboratory test with electrical-resistance strain gauges.
Deflection of uniformly loaded circular plates upon equispaced point supports
Authors: Vaughan Henry 
Published: July 2007

A simple formula is derived for predicting the flexure of uniformly loaded point-supported circular plates. The classical solution of Michell for a clamped plate under a single point load is extended for any number of point loads regularly spaced around a circle concentric with the plate edge. The resulting series for the edge moments and shears are summed and are shown to be very similar to a simple sine wave. Replacing the exact expressions by single sine waves enables the clamped edges to be set free by a simple superposition of solutions. The point reactions are equilibrated by a uniform load and the resulting deflection surface for a free uniformly loaded point-supported plate is obtained immediately. Deflection curves for the particular case of a plate supported at three points are given in the form of contours of equal deflection. This particular case is compared with some experimental results which were obtained by optical methods. For three supports, maximum deviation from the flat is least when the supports are equispaced around a circle of radius approximately two-thirds that of the plate. The contours for this case show that the central area is remarkably flat and that there are three diameters along which the deflections are almost constant.
Application of large-deflection theory to normally loaded rectangular plates with clamped edges
Authors: Scholes A 
Published: July 2007

A previous paper (1)∗described an analysis for plates that made use of non-linear large-deflection theory. The results of the analysis were compared with measurements of deflections and stresses in simply supported rectangular plates. In this paper the analysis has been used to calculate the stresses and deflections for clamped-edge plates and these have been compared with measurements made on plates of various aspect ratios. Good agreement has been obtained for the maximum values of these stresses and deflections. These maximum values have been plotted in such a form as to be easily usable by the designer of pressure-loaded clamped-edge rectangular plates.
Effect of torsional prestrain on the yield locus of 1100-F aluminium
Authors: Williams J F , Svenssoon N L 
Published: July 2007

A series of combined stress tests in torsion-tension space is carried out on thin-walled tubes of 1100-F commercially pure aluminium, prestrained to a maximum level of 10 per cent torsional plastic strain. The results are analysed in terms of a proposed, rationally based, yield criterion constructed on statistical reasoning. It is shown that during prestrain, the yield loci undergo a significant degree of distortion, accompanied by a flattening of part of the locus opposite to the loading point. It is found that the yield locus does not rotate under prestrain and, contrary to the findings for tensile prestrain, little evidence of the development of corners at the loading point is observed. The proposed criterion is shown to provide a good fit to the experimental results.
Point-loaded discs and blocks applicable to tensile testing of brittle materials
Authors: Appl F J 
Published: July 2007

A method of numerically approximating the solutions of plane-stress or plane-strain elasticity problems with boundary conditions consisting of concentrated forces or distributed loads is presented herein. The effect of each concentrated force (commonly termed a point load) that acts on the boundary is represented by a Flamant solution. Usually, the combined effect of these Flamant solutions indicates the presence of distributed loadings or ‘residual stresses’ on some portions of the boundary that are not consistent with the actual boundary conditions. The negatives of these ‘residual stresses’ are used as stress boundary conditions in a singular integral method of numerical analysis that is applicable to plane elasticity problems involving distributed loadings on the boundaries. Since the method presented herein involves only stress boundary conditions, the solutions are valid for both plane stress and plane strain. The accuracy of this superposition method is demonstrated by consideration of a circular disc or cylinder subjected to diametrically opposed concentrated forces for which accuracy to within 0.2 per cent of the exact solution is obtained. Parametric analyses of rectangular and elliptical compression members subjected to point loads are presented. Results determined herein are found to compare relatively well with those determined in previous numerical and experimental investigations of specific cases. These results make possible the design and analysis of compression members used to evaluate the tensile fracture strength of brittle materials.
Buckling of shallow torispherical domes subjected to external pressure — a comparison of experiment, theory, and design codes
Authors: Galletly G D , Kruzelecki J , Moffat D G , Warrington B 
Published: July 2007

The test results obtained on 24 externally-pressurised torispherical steel shells are given in this paper. The knuckle radius-to-diameter ratio of the domes varied from 0.06 to 0.18 and the spherical cap radius-to-thickness ratios were between 75 and 335. Initial shape and thickness measurements were carried out on all the torispheres and a summary of this information is given. The BOSOR 5 shell buckling program was employed to predict the buckling/collapse pressures of all the domes; both perfect domes and those with axisymmetric imperfections were considered. The correlation between the theoretical predictions and the experimental results was, in general, very good. The main conclusions of the present investigation are: (i) that some of the experimental buckling pressures were lower than those obtained by multiplying the BS 5500 design values by a safety factor of 1.5, and (ii) that those torispheres with sharp knuckle radii failed by plastic collapse in the knuckle region and the collapse pressures were not very sensitive to initial geometric imperfections. It thus appears that the BS 5500 rules relating to the strength of shallow torispheres subjected to external pressure need to be amended, and that the tolerances on geometric shape for cases which are likely to be imperfection-insensitive should be reconsidered.
Clamped torispherical shells under external pressure — some new results
Authors: Blachut J , Galletly G D 
Published: July 2007

Perfect clamped torispherical shells subjected to external pressure are analysed in the paper using the BOSOR 5 shell buckling program. Various values of the knuckle radius-to-diameter ratio ( r/D) and the spherical cap radius-to-thickness ratio ( Rs/ t) were studied, as well as four values of σyp, the yield point of the material. Buckling/collapse pressures, modes of failure and the development of plastic zones in the shell wall were determined. A simple diagram is presented which enables the failure mode in these shells to be predicted. The collapse pressures, pc, were also plotted against the parameter Λs (√( pyp/ pcr)). When the controlling failure mode was axisymmetric yielding in the knuckle, the collapse pressure curves depended on the value of σyp, which is unusual. However, when the controlling failure mode was bifurcation buckling (at the crown/knuckle junction), the collapse pressure curves for the various values of σyp all merged, i.e., they were independent of σyp. This latter situation is the one which normally occurs with the buckling of cylindrical and hemispherical shells. A limited investigation was also made into the effects of axisymmetric initial geometric imperfections on the strength of externally-pressurised torispherical shells. When the failure mode was axisymmetric yielding in the knuckle, initial imperfections of moderate size did not affect the collapse pressures. In the cases where bifurcation buckling at the crown/knuckle junction occurred, small initial geometric imperfections at the apex did not affect the buckling pressure, but axisymmetric imperfections at the buckle location did influence it. With the other failure mode (i.e., axisymmetric yielding collapse at the crown of the shell), initial geometric imperfections caused a reduction in the torisphere's strength.
The influence of orientation on the elastic and low cycle fatigue properties of several single crystal nickel base superalloys
Authors: Li S X , Ellison E G , Smith D J 
Published: July 2007

Experimental studies on the influences of orientation on the elastic behaviour at 20°C and 950°C and the low cycle fatigue creep properties at 950°C of the single crystal nickel base superalloy SRR99 are described. The elastic response at 20°C is found to be in good agreement with predictions from the properties of pure nickel. At 950°C the orientation dependence is shown to be well correlated with a simple orientation function, which is also found to be insensitive to temperature. Similar correlations are shown for the single crystal nickel base superalloys PWA1480 and RENE N4 at high temperatures. The low cycle fatigue properties for fully reversed strain controlled cycles of SRR99 are shown to be strongly dependent on crystal orientation. Similar results from earlier work for RENE N4 are also illustrated. It is shown that by modifying the applied total strain range to take into account the influence of orientation for elastic deformation, essentially orientation-independent low fatigue cycle curves for SRR99 and RENE N4 are obtained.
Qualitative research on breastfeeding in the UK: a narrative review and methodological reflection
Authors: Miller Tina , Bonas Sheila , Dixon-Woods Mary 
Published: July 2007

English
Levels of breastfeeding in the UK remain low compared with other European countries. Qualitative research is a potential source of important data on women’s infant feeding decisions and practices, but is currently omitted from systematic reviews in the area. We report a narrative review of qualitative studies of breastfeeding in the UK, and identify two main themes around which the literature can be organised: first, women’s experiences of infant feeding and feeding decisions; second, healthcare practices and support for breastfeeding. We also reflect on the methodological issues in conducting a review of this type.
‘What to do about political context?’ Evidence synthesis, the New Deal for Communities and the possibilities for evidence-based policy
Authors: Wright John S.F. , Parry Jayne , Mathers Jonathan 
Published: July 2007

English
If policy is the sum of interactions between agents and organisations about an appropriate course of action, then political context refers to the structural, organisational and ideological aspects of the environment relevant to those interactions. Crucially, political context may modify how ‘evidence’ is used by policy makers. In this article, we use a case study – the New Deal for Communities regeneration programme – to explore further the influence of political context on the use of evidence by policy makers. We conclude that over time, the political landscape within which the initiative is implemented becomes increasingly important in determining the use of evidence.
Measuring Drained Residual Strengths in the Bromhead Ring Shear
Authors: Meehan Christopher L. , Brandon Thomas L. , Duncan J. Michael 
Published: July 2007

Abstract
A series of Bromhead ring shear tests were conducted to measure the drained residual strength of Rancho Solano Fat Clay. Tests conducted using different test procedures demonstrate the significant effect that wall friction can have in the Bromhead ring shear device. This problem was addressed by beveling the top loading platen, which led to measurements of drained residual strength that were 21–23 % lower than those measured with the unmodified platen. Using the modified platen, similar test results can be achieved independent of the details of the test procedure that is followed, giving greater confidence in the measured residual shear strength.
The Quest for High‐Performance Host Materials for Electrophosphorescent Blue Dopants
Authors: Wu M.‐F. , Yeh S.‐J. , Chen C.‐T. , Murayama H. , Tsuboi T. , Li W.‐S. , Chao I. , Liu S.‐W. , Wang J.‐K. 
Published: July 2007

AbstractWe report a systematic comparison study of 3,5‐di(N‐carbazolyl)tetraphenylsilane (SimCP) and N,N′‐dicarbazolyl‐3,5‐benzene (mCP), which are used as the host materials for phosphorescent blue dopants in organic light‐emitting diodes (OLEDs). On the basis of photoexcitation emission spectroscopy, thermal stability analysis, photoelectron analysis, charge transport measurements, and molecular dynamics (MD) simulations, we conclude that the non‐π‐conjugated meta‐substituted triphenylsilyl moiety of SimCP exerts a unique hindering effect on the molecular packing characteristics in the condensed phase. The chemical origin of the superior performance of SimCP over mCP is revealed, and is expected to be helpful for the molecular design of effective host materials for enhancing the performance of blue phosphorescent OLEDs.