bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of Physical Foaming Agents on the Viscosity of Various Polyolefin Resins
Authors: Gendron Richard , Champagne Michel F. 
Published: April 2004

The effect of temperature and type of physical foaming agent (HCFC-142b, n-pentane, and carbon dioxide) on the shear viscosity have been investigated for various types of polyolefin resins (PP, LLDPE, and HDPE). The viscosity changes have been monitored using a commercial on-line process control rheometer mounted on a twin-screw extruder. A plasticization index, based on the respective molecular weights of the foaming agent and the repeat unit of the polymer, is proposed. Comparison with an amorphous polymer, namely polystyrene, is also made for mixtures using the same physical foaming agents.
Deformation Behavior of NiTi/Polymer Shape Memory Alloy Composites – Experimental Verifications
Authors: Murasawa Go , Tohgo Keiichiro , Ishii Hitoshi 
Published: April 2004

Composites containing NiTi shape memory alloy (SMA) long-fiber, short-fibers or Ti long-fiber in a Polycarbonate (PC) matrix have been fabricated by the injection molding technique. Also, prestrained SMA long-fiber/Epoxy matrix composites have been fabricated. The fracture behavior and thermo-mechanical deformation behavior are examined; (1) Fracture behavior – uniaxial tensile tests up to fracture for SMA long-fiber and short-fiber composite (SMAC). (2) Thermomechanical deformation behavior – tensile loading–unloading tests for Pseudoelastic (PE) long-fiber/PC matrix composites. Several thermo-mechanical loading tests for Shape Memory Effect (SME) long-fiber/PC matrix and SME long-fiber/Epoxy matrix composites were used. The obtained results are as follows: (1) The stress–strain relation up to the final fracture of the Shape Memory Alloy Composites (SMACs) showed the repeated up-and-down of the stress which corresponds to the necking of the specimen, fiber fracture, and matrix fracture. The strain for the initiation of necking and the strain for the fiber or matrix fracture in the SMACs were higher than those in the Ti composite. This is attributed to the unique stress–strain relations accompanied by the stress-induced martensitic transformation of the SMA fibers. (2) The SMAC containing PE fiber and PC exhibited the pseudoelastic-like deformation under tensile loading–unloading. (3) The SMAC containing SME fiber and PC exhibited the large contraction by heating after tensile loading–unloading, but the compressive residual stress in the matrix expected in this process was not remarkable. However, compressive residual stress in the matrix may become greater by embedding prestrained fiber in the matrix.
Measurement Research of Parameter on Three-Dimensional Braided Composite Material Preform Surface
Authors: Wan Zhenkai , Li Jialu 
Published: April 2004

This paper describes a new measuring algorithm for three-dimensional (3-D) braided composite materials preform exterior average braided angle based on image texture. In this project, an advanced nonlinear filtered algorithm for image of 3-D braided composite materials preform was developed. The digital signal processor, TMS320C/F240, has been used as a device for the preform exterior image filtering. The nonlinear filter consisted of minimum, median, and maximum filters. The DUAL PORT RAM, TC514256, has been used as image buffer. The proposed implementations achieve more powerful and stable noise reduction than commercial algorithms. In this research we also propose a more effective and rapid system design method and describe the procedure and how to implement our proposed algorithms by using the surface image testing system. A real time preform surface image collecting and filtering system was developed without PC controlling (the FPGA technology and digital signal process were used). To show the effectiveness of the proposed designing scheme, angular power spectrum algorithms were designed and it generated an optimized and portable code using assemble and VC language; then it was downloaded to a PC. It built programs that helped speed up the system so as to produce high quality results in less time. Experimental results show that the proposed method is feasible. The research was appraised by Science & Technology Committee of Tianjin. The appraisal report shows the research is advanced in the world. So far, the research is a new development for 3-D braided composite material preform measuring. It will provide the perfect data for improving artifact technology for 3-D braided composite material preform.
Analysis and Optimization of a Pressurized Mid-plane Asymmetric Noncircular Sandwich Fuselage
Authors: Chen Zhaohui , Vinson Jack R. 
Published: April 2004

For efficient cargo space in a global range transport aircraft, a noncircular cross-section fuselage is investigated. The cross-section investigated is a rectangle with rounded corners. In order to minimize the resulting bending stresses, sandwich construction is investigated, and in particular a mid-plane asymmetric construction is studied to utilize bending stretching coupling to minimize these bending stresses still further in the sandwich construction. Traditionally, in almost all cases of sandwich constructions to date, the construction is mid-plane symmetric, i.e. the faces are of the same material and thickness. There are many needs for sandwich constructions using different faces. For example, for a racing boat, one face is subjected to corrosion, the other face is primarily subjected to an internal environment. On the other hand, considering that many advanced composite materials have different strengths and elastic moduli in tension and compression, even if the two faces are made of the same material, different face thickness can provide a superior structure. The governing equations are obtained by applying the Theorem of Minimum Potential Energy and displacements are assumed. Solutions are derived for a non-circular shell, involving a mid-plane asymmetric sandwich construction that are subjected to a constant internal pressure for the structure with flat sides and rounded corners. The shell is simply supported at both ends. Solutions are obtained through piece-wise matching of plate and shell sections.
Variation in Average Costs among Federally Sponsored State-Organized Cancer Detection Programs: Economies of Scale?
Authors: Mansley Edward C. , Duñet Diane O. , May Daniel S. , Chattopadhyay Sajal K. , Mckenna Matthew T. 
Published: April 2004

Background Societal cost-effectiveness analysis and its variants help decision makers achieve an efficient allocation of resources across the set of all possible health interventions. Sometimes, however, decision makers are focused instead on the efficient allocation of resources within a particular intervention program that has already been implemented. This is especially true when the intervention is being delivered at several different sites. An analysis of average cost across program sites may help program officials to maximize the health benefits that can be achieved with limited resources. In this article, the authors present such an analysis, with special attention paid to the possible existence and implications of economies of scale. Methods Focusing on federally sponsored, state-organized cancer detection programs, the authors modeled 19 state programs as productive processes and examined their average costs over a 2- to 5-year period of operation. They considered 3 alternative definitions of output: women served, screens performed, and conditions detected. Average federal costs and average total costs were estimated for each grant period. Multivariate regression analysis was used to help explain the variation in average costs. Results The average cost estimates were distributed in a skewed pattern with the majority of observations falling close to the median and substantially below the mean. For all measures considered, average cost decreased as output expanded. This inverse relationship between average cost and output level persisted even after controlling for the effects of other predictors, suggesting the possible existence of economies of scale. Discussion The potential existence of economies of scale calls into question the assumption of a constant average cost frequently made in economic analyses of proposed public health programs. It also implies that a) differences in output level should be taken into account when comparing operating efficiency across program sites; b) conclusions from societal cost-effectiveness analyses may depend on the level of output at which the programs are evaluated; c) cost projections could be inaccurate if they do not take into account the decrease in average cost that occurs as output expands; and d) gains might be possible if similar programs with limited output potential are integrated, perhaps through cost sharing.
Modeling the Public Health Response to Bioterrorism: Using Discrete Event Simulation to Design Antibiotic Distribution Centers
Authors: Hupert Nathaniel , Mushlin Alvin I. , Callahan Mark A. 
Published: April 2004

Background Post-exposure prophylaxis is a critical component of the public health response to bioterrorism. Computer simulation modeling may assist in designing antibiotic distribution centers for this task. Methods The authors used discrete event simulation modeling to determine staffing levels for entry screening, triage, medical evaluation, and drug dispensing stations in a hypothetical antibiotic distribution center operating in low, medium, and high disease prevalence bioterrorism response scenarios. Patient arrival rates and processing times were based on prior mass prophylaxis campaigns. Multiple sensitivity analyses examined the relationship between average staff utilization rate (UR) (i.e., percentage of time occupied in patient contact) and capacity of the model to handle surge arrivals. Results Distribution center operation required from 93 staff for the low-prevalence scenario to 111 staff for the high-prevalence scenario to process approximately 1000 people per hour within the baseline model assumptions. Excess capacity to process surge arrivals approximated (1-UR) for triage staffing. Conclusions Discrete event simulation modeling is a useful tool in developing the public health infrastructure for bioterrorism response. Live exercises to validate the assumptions and outcomes presented here may improve preparedness to respond to bioterrorism.
Smart Material-Actuated Rotor Technology – SMART
Authors: Straub Friedrich K. , Kennedy Dennis K. , Domzalski David B. , Hassan Ahmed A. , Ngo Hieu , Anand V. , Birchette Terry 
Published: April 2004

Vibration, noise, and aerodynamic design compromises are primary barriers to further improvements in effectiveness of the helicopter. The MD900 light utility helicopter main rotor system is modified to include in-blade smart material actuation for active control. A piezoelectric (PE)-driven trailing edge flap is used for vibration, noise, and aerodynamic performance improvements. A shape memory alloy (SMA)-driven trailing edge trim tab is used for in-flight blade tracking. Sizing and conceptual design of an active flap and trim tab system for the MD900 helicopter were completed. Several two-dimensional airfoil and flap/tab models were wind tunnel tested and an aerodynamic database was established. Structural samples of the flap actuator mounts, flap section, tab, and full-span flap were fabricated and successfully tested. Several prototype actuators were developed and extensively tested to establish their performance and robustness in the dynamic operating environment. The flap actuator uses two biaxial PE stack columns, operating in a push pull mode, a column mid-support, and a stroke amplification mechanism. The tab actuator uses two biaxial SMA tubes for actuation/bias, an SMA-activated lock for power-off operation, and integrated microprocessor control electronics. Results to date confirm that smart material in-blade active control of a rotor is feasible and offers significant performance and cost benefits. Projected payoffs from reduced vibrations and noise as well as in-flight tracking include improved component lives, reduced maintenance and improved crew, passenger, and community acceptance.
Wrinkling of Composite-facing Sandwich Panels Under Biaxial Loading
Authors: Birman Victor , Bert Charles W. 
Published: April 2004

The problem of face wrinkling in sandwich structures was identified as an important failure mode and first analyzed in 1940 by Gough et al. [1], who used a Winkler-type elastic foundation to model the core. This work was followed by experiments and further analysis by many others. Until 1966 all of the research was devoted to uniaxial compression loading. However, in many applications, such as naval and aircraft structures, panels are subjected to biaxial loading. Such loadings were first analyzed by Plantema in 1966 [2] for the case of sandwich constructed of isotropic materials. Sullins et al. [3] suggested an interaction equation that can be used as a criterion of wrinkling under compression in the principal directions. This equation is formulated in terms of the ratios of the principal compressive stresses to the corresponding wrinkling stresses. More recently Fagerberg [4, 5] and Vonach and Rammerstorfer [6] considered the case of sandwich with orthotropic facings. The present work attacks the subject problem using three different models for the core. One model uses a simple Winkler elastic foundation approach. The second model, following Hoff and Mautner [Hoff, N.J. and Mautner, S.E. (1945). The Buckling of Sandwich-Type Panels, Journal of the Aeronautical Sciences, 12: 285–297.], uses a linear model for the decay in deformation from the core-facing interface, while the third model, following Plantema [Plantema, F.J. (1966). Sandwich Construction, John Wiley & Sons, Inc., New York.], uses an exponential decay.
The big ‘OE’
Authors: Bell Claudia 
Published: April 2004

‘OE’ stands for ‘overseas experience,’ a cultural institution in New Zealand. This rite of passage for young adults is an extended journey overseas. While little examined in academia, OE is clearly understood in everyday life, and well documented in fiction and in literary biographies. The journey is a quest or pilgrimage from one of the world’s most remote countries, to the places familiar in national and family histories, popular media, and in tales from previous OE travellers. This article identifies these young travellers as ‘secular pilgrims’, as they re-enact familiar rituals of departure, arrival and return. Parallels are drawn with the work of Coleman and Elsner on religious pilgrimages. The New Zealanders are undertaking a rite of passage, a ritual, a journey with metaphorical resonances, and while doing so they are collecting narratives of adventure and returning with tokens of place. Their low budgets test the acclaimed national characteristics of independence and initiative. National difference is reflected upon: from a distance myths of place - home - intensify. The return home provides an audience for travel narratives. A rite of passage has been achieved.
Medical Chemists and the Origins of Clinical Chemistry in Britain (circa 1750–1850)
Authors: Coley Noel G 
Published: April 2004

AbstractIn this history, I review developments leading toward the establishment of clinical chemistry in Britain. Chemical research by certain physicians occurred in the context of medical traditions founded on vitalism, distillation analysis, and limited chemical knowledge. Urine chemistry figured prominently in this period together with the analysis of kidney and bladder stones. Bright’s team studying albuminuria was the first clinical research school in Britain, whereas Prout’s survey of physiological chemistry, based on meticulous attention to analysis, was the best summary of human metabolism before Liebig’s Animal Chemistry. Liebig’s ideas influenced all physicians who were interested in chemistry. Henry Bence Jones based his medical practice on Liebig’s theories. His research relating urinary phosphates to diet and exercise revealed the so-called Bence Jones proteins and investigated the distribution and persistence of drugs in the body. J.L.W. Thudichum used analytical skills learned from Liebig in his brain chemistry work. George Owen Rees investigated urine analysis and the relationship between urine and blood, using Liebig’s practical methods while condemning an uncritical acceptance of his theories. These and similar studies showed that chemistry could improve clinical medicine, and because it could also reveal the onset of disease even before clinical symptoms developed, it offered valuable support to preventive medicine. However, so many physicians resisted the introduction of chemistry that progress toward the establishment of clinical chemistry in nineteenth-century Britain was slow.
Deconvolution of alpha liquid scintillation spectra for quantitative analysis of actinide elements in water samples
Authors: Aupiais Jean 
Published: April 2004

Summary
The reliability and accuracy of actinide measurement in environmental samples strongly depend on the α-spectrum deconvolution process used to identify all radionuclides present in the sample, and the necessity to take into account internal conversion is demonstrated. In this process, all actinides can be resolved as the sum of three peaks: the main alpha transition and two sum peaks for which the additional α ray is merged with the internal conversion on L-shell peak and with all other conversions on M-shell, N-shell, etc.

The intensity of the internal conversions for thorium, uranium, plutonium and americium have been calculated and normalised to the intensity of the main alpha transition. These data can be used to determine the activity of any above-mentioned actinide by alpha liquid scintillation with alpha/beta discrimination. The quantitative analysis and the isotopic ratio determination of several certified solutions of actinides demonstrate the validity of this approach.
An EXAFS and TRLFS study of the sorption of trivalent actinides onto smectite and kaolinite
Authors: Stumpf Thorsten , Hennig C. , Bauer A. , Denecke Melissa A. , Fanghänel Th. 
Published: April 2004

Summary
The structure parameters of the Am3+ aquo ion and of Am(III) sorbed onto smectite and kaolinite at varying pH are analyzed using EXAFS. An Am-O distance of 2.47-2.49Å is found and a coordination number of 8-9 oxygen atoms is observed for the Am3+ and its hydration sphere. Combined TRLFS (Cm(III)) and EXAFS (Am(III)) results show that An(III) sorbs onto smectite at pH 4, forming an outer-sphere complex and retains its complete primary hydration sphere. With increasing pH, inner-sphere sorption onto smectite and kaolinite occurs. The overall number of oxygen atoms coordinating the actinide ion remains about the same at pH 6, with four water molecules being replaced by oxygen atoms from the mineral surface during inner-sphere complex formation. The coordination number of sorbed Am(III) at pH 8 exhibits an apparent decrease, which may be affected by the formation of ternary OH-/Am/clay mineral surface species.
Molecular characterization of inv dup del(8p): Analysis of five cases
Authors: Shimokawa Osamu , Kurosawa Kenji , Ida Tomoko , Harada Naoki , Kondoh Tatsuro , Miyake Noriko , Yoshiura Kohichiro , Kishino Tatsuya , Ohta Tohru , Niikawa Norio , Matsumoto Naomichi 
Published: April 2004

AbstractWe analyzed five patients with inverted duplication deletion of 8p [inv dup del(8p)] using fluorescence in situ hybridization (FISH) and short tandem repeat polymorphism (STRP) analysis. In all patients, inv dup del(8p) consisted of a deleted distal segment, an intact in‐between segment, and a duplicated proximal segment. In all of them, the proximal breakpoint of the deletion and one of the breakpoints of the duplication were identical, each located at one of the two olfactory receptor gene clusters at 8p23. FISH analysis showed all their mothers to be heterozygous carriers of an 8p23 inversion [inv(8)(p23)]. STRP analysis indicated that the deletions occurred in maternally derived chromosomes. The duplicated segments had two copies of maternal, either heterozygous or homozygous alleles. These findings support and reinforce those in 16 patients with inv dup del(8p) and their parents by Floridia et al. [1996: Am J Hum Genet 58:785–796] and subsequent additional studies of 10 of them by Giglio et al. [2001: Am J Hum Genet 68:874–883]. Based on these findings, we propose a model for the inv dup del(8p) formation. The inverted segment and its normal counterpart in inv(8)(p23) heterozygous carrier mothers form a loop at the pachytene period of meiosis I. Inv dup del(8p) with heterozygous duplication is formed through at least one meiotic recombination within the loop. Inv dup del(8p) with the homozygous duplication arises through two meiotic recombinations on the inv(8)(p23) chromosome (one within the loop and the other between the loop and centromere). Subsequent rescue by eliminating a part of the duplicated segment and a centromere enables formation of viable inv dup del(8p). The frequency of the inv(8)(p23) allele is 39% in a normal Japanese population, comparable to 26% in Europeans Giglio et al. [2001: Am J Hum Genet 68:874–883]. The proposed mechanism of formation of inv dup del(8p) requires two independent events (a recombination within the loop and subsequent rescue), which may explain its rarity. © 2004 Wiley‐Liss, Inc.
COMT: A common susceptibility gene in bipolar disorder and schizophrenia
Authors: Shifman Sagiv , Bronstein Michal , Sternfeld Meira , Pisanté Anne , Weizman Avraham , Reznik Ilya , Spivak Baruch , Grisaru Nimrod , Karp Leon , Schiffer Richard , Kotler Moshe , Strous Rael D. , Swartz‐Vanetik Marnina , Knobler Haim Y. , Shinar Eilat , Yakir Benjamin , Zak Naomi B. , Darvasi Ariel 
Published: April 2004

AbstractA variety of psychiatric illnesses, including schizophrenia and bipolar disorder, have been reported in patients with microdeletion on chromosome 22q11—a region which includes the catechol‐O‐methyltransferase (COMT) gene. The variety of psychiatric manifestations in patients with the 22q11 microdeletion and the role of COMT in the degradation of catecholamine neurotransmitters may thus suggest a general involvement of the COMT gene in psychiatric diseases. We have previously reported on a significant association between a COMT haplotype and schizophrenia. In this study, we attempt to test for association between bipolar disorder and the polymorphisms implicated in schizophrenia. The association between COMT and bipolar disorder was tested by examining the allele and haplotype found to be associated with schizophrenia. A significant association between bipolar disorder and COMT polymorphisms was found. The estimated relative risk is greater in women, a result consistent with our previous findings in schizophrenia. We suggest that polymorphisms in the COMT gene may influence susceptibility to both diseases—and probably also a wider range of behavioral traits. © 2004 Wiley‐Liss, Inc.
Catalytic activities of amino acid modified, starch‐grafted acrylamide for the decomposition of hydrogen peroxide
Authors: El‐Hamshary Hany , Al‐Sigeny Samia 
Published: April 2004

AbstractAcrylamide was grafted onto corn starch with ceric(IV) ions as an initiator. Starch‐graft‐polyacrylamide was modified with amino acids through a reaction with the sodium salts of glycine, β‐alanine, and phenylalanine. The catalytic activities of the iron(III) complexes of the amino acid modified grafted materials were investigated for the decomposition of hydrogen peroxide (H2O2). These new polymeric supports were found to be active in the catalytic decomposition of H2O2. The extent of decomposition varied with the composition of the support. The iron(III) complex of the glycine‐modified material was the most active of the amino acid supported catalysts. Factors that affected the rate of reaction, such as the concentration of H2O2, the amount of the catalyst, the pH, and the temperature, were investigated. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 630–636, 2004