bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of the Chemical Composition of Glass on Heat Transfer through Glass Fibre Insulations in Relation to Their Morphology and Temperature of Use
Authors: Langlais C. , Guilbert G. , Banner D. , Klarsfeld S. 
Published: March 2007

This paper represents the synthesis of our investigations towards a better understanding of radiative heat transfer through fiberglass insulating materials from 1985 to 1990. Both a theoretical and experimental approach are proposed in order to predict the thermal resistance of fibrous insulants, and to determine the influence of the chemical composition of the bulk glass, of the insulant morphology (porosity, specific surface, anisotropy) and of the temperature of use ( T < 600°C). The fibrous material is treated as a semi-transparent medium that absorbs, scatters and emits radiation; the radiative heat transfer equation is solved by the Shuster- Schwartzchild approximation. The radiative coefficients of the fiberized glass that ap pear in the equations (scattering, absorption and backscattering coefficients) are derived from spectral reflection and transmission measurements performed on the bulk glass as a function of temperature (determination of the complex index and use of Kerker Mie theory). Theoretical predictions of the total heat transfer through different types of fiberglass insulants are presented and validated by experimental results. The emphasis is put on the effect of the chemical composition of glass. Special at tention is given to boron oxide (B2O 3). A close look at the infrared spectra (on both bulk and fiberized glass) allows us to understand the influence of this oxide on the thermal resistance of fiberglass insulating materials. The effects of the insulant morphology and temperature are also discussed.
Thermal Performance Patterns on Solid Masonry Exterior Walls of Historic Buildings
Authors: Colantonio Antonio 
Published: March 2007

The Parliamentary Precinct in Ottawa, Canada, is comprised of a number of historic buildings that include the House of Commons, the Senate Chamber, the Parliamentary Library, the Peace Tower, and other buildings that pro vide offices for parliamentarians and their staff. The majority of these buildings have exterior walls that are made of solid masonry with thicknesses ranging between 400 mm and 800 mm. In some cases, special wall areas are more than 1200 mm thick and are comprised of various types of masonry materials. With winter design tempera tures of-25°C, more than 170 cm of snowfall, and numerous thaws during the five month heating season, the exterior environmental conditions acting on the exterior wall assemblies of these historic buildings are severe enough to cause masonry and mortar deterioration wherever moisture accumulates during winter months. Infrared thermographic inspections were carried out to locate and identify the causal mechanisms of moisture accumulation within masonry wall assemblies. This paper will discuss the types of thermal patterns produced by various mechanisms of heat loss and identify some of the typical areas where possible masonry deterioration occurs. Knowledge gained from these extensive investigations will be used to de velop a nondestructive test methodology to locate areas of freeze-thaw damage as part of a predictive and preventive maintenance program to reduce preservation costs of these historical structures.
Book Reviews : Developing Quality Schools, edited by Colin Bayne-Jardin and Peter Holley, London: Falmer Press, 1994, 153 pp
Authors: Brown Dan 
Published: March 2007

Books applicable to the broad field of program evaluation are reviewed. Books may be reviewed singly or in groups to illuminate similarities and differences in intent, philosophy, and usefulness. Persons with suggestions of books to be reviewed, or those who wish to submit a review, should contact Perry Sailor (Department of Psychology, Utah State University, Logan, UT 84322-2810; phone: 801-797-0090 or e-mail: perrys@cpd2.usu.edu). In general, a review of an individual book should not exceed four double-spaced typewritten pages; groups of books may require additional lengths. In the past, EP policy has been to commission a single review for each book. That will continue to be the practice for most books, but in the future, two reviews will be commissioned for books judged by the Editor and/or Book Review Editor to be major works in evaluation. Such major evaluation books would include evaluation texts, edited books of evaluation readings, or other books dedicated solely to extending evaluation theory or practice. Conversely, books that focus on methods or techniques shared by evaluation and other disciplines or professions (e.g., statistics; measurement; observation methods) will receive a single review.
Race, Social Class and the Motive to Avoid Success in Women
Authors: Weston Peter J. , Mednick Martha T. 
Published: March 2007

This study sought to examine race and social class differences in the expression of fear of success in women. This concept, termed the Motive to Avoid Success (M-s), was developed and utilized by Horner (1968) to explain sex differences in achievement motivation. In our study, M-s imagery expressed in response to TAT-verbal cues was compared for black and white college women and two social class levels. The hypothesis that black women would show less M-s than white women was supported. The findings held for subjects at two schools and for two verbal cues. Social class differences were not found. Several interpretations and suggestions for follow-up studies are given.
Review : Maintaining and measuring quality care: a discussion of the Maxwell Approach
Authors: Young Jeanine 
Published: March 2007

■ Quality assurance and audit ensures that standards are maintained and resources are used effectively ■ Maxwell's Dimensions of Health Care Quality facilitate the establishment of concise standards covering every aspect of the neonatal service ■ A bottom up-top led approach to quality empowers midwives and neonatal nurses to retain or win back the service in which they are the main provider
Conceptual and Policy Issues in Rules of Origin: Implications for SAPTA and SAFTA
Authors: Panchamukhi VR , Das Ram Upendra 
Published: March 2007

Rules of origin are applied in both preferential and non-preferential trading regimes. The system of rules of origin has been a very useful mechanism in identi fying the origin of goods for the adoption of various commercial policies such as anti-dumping duties, countervailing duties and voluntary restraint arrangements. It has also been used in preventing trade deflection in regional trading arrange ments. The present article argues that it also plays a developmental role in a coun try or region. However, rules of origin should be designed in a manner that is not trade restricting. They should not become trade barriers due to their complex methods of implementation. The countries of SAARC have been making progress on various fronts of regional economic cooperation. In this context, the present study weighs the pros and cons of relaxation of the rules of origin requirements under the SAPTA regime. As SAARC countries progress from SAPTA to SAFTA, an efficacious sys tem of granting originating status to products would be required. The article also tries to evolve an approach for setting in place a SAFTA rules of origin system by taking into account various SAARC region-specific characteristics. It further takes into consideration the present status of WTO negotiations on non-preferential rules of origin.
Effects of Anti-Block/Processing Aid Combinations On Lldpe Blown Film Extrusion
Authors: Blong Thomas J. , Duchesne Denis 
Published: March 2007

Anti-block agents differing in composition, structure, and surface coating were compounded with fluorocarbon elastomer polymer processing aids (PPAs) in linear low density polyethylene. Separate and combined masterbatches of 20% anti-block and 2% PPA were melt mixed and let down to 5000 ppm and 500 ppm respectively. Preliminary investigation of the combined PPA/anti-block masterbatches by capil lary rheometer identified wide ranging differences when comparing equilibrium melt viscosity and melt fracture onset. Synthetic silicas appeared to show the great est decrease in PPA performance while ceramic micro-spheres caused little change. Further studies were conducted on a commercial film line at shear rates of 750 s-1. Results showed that the PPA was generally more effective when incorporated as a separate masterbatch than when compounded with the anti-block. For example, melt fracture could only be eliminated in the presence of diatomaceous earth and the PPA when the two were compounded separately. In the case of calcium carbonate and ceramic spheres, melt fracture was eliminated in the combined samples but equilib rium pressures were higher and equilibrium times were longer. Coated silicas showed less interference with PPA performance than did their uncoated analogs when used in a combined masterbatch.
Slow Rate Penetration of Packaging Films
Authors: Seyler Rick J. 
Published: March 2007

A detailed evaluation of the slow rate penetration resistance measure ment was conducted on twenty-two different monolithic, coextruded, or laminated flexible barrier packaging films using five different probe geometries. No universal change in penetration resistance with penetration rate was found. Decreasing probe sharpness or severity increased the observed penetration resis tance and improved the signal-to-noise ratio. However, similar rankings of film per formance were possible regardless of probe geometry. After considering these and many other factors, it is recommended that measurement of slow rate penetration re sistance should be made using a 20 mm/min penetration rate and a 3 2 mm dia hemispherical probe with a probe:clamp diameter ratio of 10.
MR image segmentation using vector decomposition and probability techniques: A general model and its application to dual‐echo images
Authors: Kao Yi‐Hsuan , Sorenson James A. , Winkler Stefan S. 
Published: March 2007

AbstractA general model is developed for segmenting magnetic resonance images using vector decomposition and probabilfty techniques. Each voxel is assigned fractional volumes of q tissues from p differently weighted images (q ≤ p + 1) in the presence of partial‐volume mixing, random noise, and other tissues. Compared wtth the eigenimage method, fewer differently weighted images are needed for segmenting the q tissues, and the contrast‐to‐noise ratio in the calculated fractional volumes is improved. The model can produce com‐posrte tissue‐type images similar to that of the probability methods, by comparing the fractional volumes assigned to different tissues on each voxel. A three‐tissue (p = 2, q = 3) model is illustrated for segmenting three tissues from dual‐echo images. M provides statistical analysis to the algebraic method. A three‐compartment phantom is segmented for validation. Two clinical examples are presented.
Statistical methods of estimation and inference for functional MR image analysis
Authors: Bullmore Edward , Brammer Michael , Williams Steve C. R. , Rabe‐Hesketh Sophia , Janot Nicolas , David Anthony , Mellers John , Howard Robert , Sham Pak 
Published: March 2007

AbstractTwo questions arising In the analysis of functional magnetic resonance imaging (fMRI) data acquired during periodic sensory stimulation are: i) how to measure the experimentally determined effect in fMRI time series; and ii) how to decide whether an apparent effect is significant Our approach is first to fit a time series regression model, including sine and cosine terms at the (fundamental) frequency of experimental stimulation, by pseudogeneralized least squares (PGLS) at each pixel of an image. Sinusoidal modeling takes account of locally variable hemodynamic delay and dispersion, and PGLS fitting corrects for residual or endogenous autocorrelation in fMRI time series, to yield best unbiased estimates of the amplitudes of the sine and cosine terms at fundamental frequency; from these parameters the authors derive estimates of experimentally determined power and its standard error. Randomization testing is then used to create inferential brain activation maps (BAMs) of pixels significantly activated by the experimental stimulus. The methods are illustrated by application to data acquired from normal human subjects during periodic visual and auditory stimulation.
Myocardial perfusion modeling using MRI
Authors: Larsson Henrik B. W. , Fritz‐Hansen Thomas , Rostrup Egill , Søndergaard Lars , Ring Poul , Henriksen Ole 
Published: March 2007

AbstractIn the present study, it is shown that it is possible to quantify myocardial perfusion using magnetic resonance imaging in combination with gadolinium diethylenetriaminopentaacetic acid (Gd‐DTPA). Previously, a simple model and method for measuring myocardial perfusion using an inversion recovery turbo‐FLASH (fast low‐angle shot) sequence and Gd‐DTPA has been presented. Here, an extension of the model is presented taking into account fast and slow water exchange between the compartments, enabling the calculation of the unidirectional influx constant (KJ for Gd‐DTPA, the distribution volume of Gd‐DTPA (A), the vascular blood volume (Vb), and the time delay through the coronary arteries (AT). The model was evaluated by computer simulation and used on experimental results from seven healthy subjects. The results in the healthy volunteers for a region of interest placed in the anterior myocardial wall were (mean ± SD) Ki=54 ± 10 ml/100 g/min, λ=30 ± 3 ml/100 g, Vb=9 ± 2 ml/100 g, ΔT=3.2 ± 1.1 s. These results are in good agreement with similar results obtained by other methods.
Design of conformationally rigid dimeric MRI agents
Authors: Shukla Rajesh , Fernandez Maria , Pilial Radhakrishna K. , Ranganathan Ramachandran , Ratsep Peter C. , Zhang Xun , Tweedle Michael F. 
Published: March 2007

AbstractThe conformational flexibility of the linkage mechanism or tether between paramagnetic metal centers is explored to assess optimal structural characteristics of multirneric MRI contrast agents. Two dimeric paramagnetic chelates differing in linkage flexibility but similar in symmetry are compared. Relaxivity, water hydration number, and reorientation times of the chelate groups are obtained, and the results demonstrate that greater linkage flexibility reduces overall relaxiv′rty.
Quantitative tissue sodium concentration mapping of normal rat brain
Authors: Christensen James D. , Barrère Bertrand J. , Boada Fernando E. , Vevea J. Michael , Thulborn Keith R. 
Published: March 2007

AbstractA quantitative in vivo method for obtaining maps of tissue sodium concentration (TSC) by MRI is compared to the invasive, global 22Na radionuclide dilutional technique in the normal rat brain. The MR method uses a three‐dimensional projectional acquisition scheme to minimize signal losses from transverse relaxation. Internal calibration standards are used to convert the signal intensity into TSC after correction for B1 inhomogeneities by using the ratio of 23Na and 1H images obtained with identical B1 distributions and sensitivities at the two frequencies. Over the biological range of concentrations, the TSC, measured as the ratio of MR signals of 23Na and 1H, gives a linear response with concentration. In the normal rat brain, the mean TSC measured using the MRI method (TSC = 45 ± 4 mM, animals = 5) is not significantly different from the global 22Na radionuclide method (TSC = 49 ± 6 mM, animals = 7).
Aluminum‐27 nuclear magnetic resonance spectroscopy and imaging of the human gastric lumen
Authors: Kaspar Armin , Bilecen Deniz , Scheffler Klaus , Seelig Joachim 
Published: March 2007

AbstractAluminum NMR is proposed as a new imaging and spectroscopy modality. Its potential is exemplified by in vivo studies of the human stomach. The dissolution kinetics of aluminum‐containing drugs at physiological doses and their removal from the human stomach have been followed by 27Al magnetic resonance spectroscopy (MRS). Aluminum concentrations as low as 0.5 mg Al3+ in the human stomach can be detected. The time course of gastric emptying has been visualized with 27Al magnetic resonance imaging (MRI) under normal conditions and in the presence of an antimuscarinic agent, which reduces the gastric motor function. 27Al MRI is the only direct method to visualize the gastric pH. 27Al MRI opens new possibilities for medical and pharmaceutical science.
In vivo MR imaging and spectroscopy using hyperpolarized 129Xe
Authors: Wagshul Mark E. , Button Terry M. , Li Haifang F. , Liang Zhengrong , Springer Charles S. , Zhong Kai , Wishnia Arnold 
Published: March 2007

AbstractHyperpolarized 129Xe has been used to obtain gas phase images of mouse lung in vivo, showing distinct ventilation variation as a function of the breathing cycle. Spectra of 129Xe in the thorax show complex structure in both the gas phase (−4 to 3 ppm) and tissue‐dissolved (190‐205 ppm) regions. The alveolar gas peak shows correlated intensity and frequency oscillations, both attributable to changes in lung volume during breathing. The two major dissolved peaks near 195‐200 ppm are attributed to lung parenchyma and to blood; they reach maximum intensity in 5‐10 s and decay with an apparent T1 of 30 s. Another peak at 190 ppm takes 20‐30 s to reach maximum; this must represent other well‐vascularized tissue (e.g., heart and other muscles) in the thorax. The maximum integrated area of the tissue components reaches 30–80% of the maximum alveolar gas area, indicating that imaging at tissue frequencies can be achieved.
Determination of knee joint cartilage thickness using three‐dimensional magnetic resonance chondro‐crassometry (3D MR‐CCM)
Authors: Eckstein Felix , Gavazzeni Antonia , Sittek Harald , Haubner Michael , Lösch Andreas , Milz Stefan , Englmeier Karl‐Hans , Schulte Erik , Putz Reinhard , Reiser Maximilian 
Published: March 2007

AbstractThe objective of this article was to analyze the accuracy and precision with which the quantitative distribution of articular cartilage can be determined in the knee joint using MRI. A three‐dimensional (3D) technique that accounts for the out‐of‐plane deviation of the interface normal in strongly curved joint surfaces (3D MR‐CCM) has been developed for cartilage thickness measurements. Eight cadaveric knee‐joint specimens and six volunteers were imaged using a fat‐suppressed gradient‐echo sequence at a resolution of 2 × 0.31 × 0.31 mm3. Cartilage volumes and topographical thickness maps were obtained and compared with those derived from anatomical sections by image analysis. The deviation of the MR volumes from those of the sections was 1–12%, the coefficient of variation after repositioning ranged from 2.9% (patella) to 8.2% (lateral tibial plateau). Between 60% and 80% of all image points could be attributed to identical thickness intervals, less than 20% deviating by more than 0.5 mm. The intraobserver and interobserver reproducibilities were very high in both the specimens and the volunteers. In the knee joint, 3D reconstructions of the cartilages, and measurements that take into account the out‐of‐plane deviation of the interface normals (3D MR‐CCM), are required.
Disadvantaged Adult Learners: Can Career Counseling Enhance Adult Education Program Effectiveness?
Authors: Champagne Delight E. 
Published: March 2007

The purpose of this study was to assess the long-term impact of career counseling on the career development of educationally disadvantaged adult education students. Follow-up questionnaires were mailed to former adult students who participated in adult education classes between 1979 and 1982. The former students had been exposed to two treatments, basic education classes plus career counseling and basic education classes without career counseling. Eleven dependent variables were examined: (a) educational participation, (b) educational certificate attainment, (c) dependence on public assistance, (d) employment status, (e) self-satisfaction, (f) length of employment, (g) employment gains, (h) income, (i) job satisfaction, (j) length of unemployment, and (k) job-hunting confidence. Multivariate Analyses of Covariance revealed that career counseling has a positive impact on some career development variables of educationally disadvantaged adult learners.
The Structure of Domain Hierarchies Found Within a Domain Referenced Testing System
Authors: Macready George B. 
Published: March 2007

The purpose of this study was to assess conditional states of item mastery found among items from different item domains and the effectiveness of various procedures for identifying such conditional relations. The item domains considered were from the curriculum area of multiplication of whole numbers, and were defined by a domain referenced testing system. It was possible to infer from the results of this study that the domain referenced testing system considered produced items which across domains showed strong conditional relations. Comparisons of goodness of fit were made among domain hierarchies with similar numbers of specified conditional relations generated by two different empirical procedures and by experts judgment. Additional comparisons were made among models generated by the same procedure but with different numbers of specified conditional relations. Support for the validity of empirically generated hierarchies with moderate numbers of conditional relations among domains was provided. However, similar support was not provided for the conditional relations hypothesized to exist by subject matter experts.
The Relationship of Clustered Interest Measures and Declared College Major: Concurrent Validity of the Copsystem Interest Inventory
Authors: Knapp Robert R. , Knapp Lila , Michael William B. 
Published: March 2007

The present study was undertaken to determine the relationship between declared major of entering college freshmen and measured interests in terms of clustered occupational activities. The sample consisted of 336 entering college freshmen who took the COPSystem Interest Inventory as part of a college orientation program and who had declared their major. The cluster representing declared major and the peak measured interest clusters were determined for each student. A test of goodness of fit of the observed to expected frequencies for these clusters gave chi-squares which were significant at the .01 level in all cases. When the three highest interest groups were examined, 71% of the students would have had a correct prediction of the cluster containing their declared major. Ninety-two percent had interest scores greater than those of 50% of the norm population in the cluster determined by their declared major. Analyses of data in the present study demonstrate that declared college major upon entry to college is meaningfully related to and thus predictive of measured occupational interest clusters. The declared major of students is more likely to be classified within one of their three highest interest clusters as measured by the COPSystem Interest Inventory than within any other cluster. Results of the present study support the use of the instrument as a tool to help entering college students select an appropriate major.
The Integration of Composite Structures into Aircraft Design
Authors: Waddoups M.E. , Jackson S.K. , Rogers C.W. 
Published: March 2007

Advanced composite materials are significantly different from conven tional aircraft materials. These differences between the two are such that all facets of airplane design are significantly affected when use of advanced composite materials is considered. Examples of the impact of composite application to a lightweight fighter design, with regard to configuration and structural integrity, are given in this paper.