bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on roll force and dynamic recrystallization of high-strength interstitial-free steels in hot rolling
Authors: Byon S M , Kim S I , Lee Y
Published: October 2006

This paper presents a constitutive model for two interstitial-free (IF) steels that can be used for calculating the roll force during hot rolling. The constitutive models assume that the deformation behaviour of material can be described with reference to strain, strain rate, and temperature together with the volume fraction of dynamically recrystallized grains. The two IF steels are Nb-Ti-added IF steel containing 0.001 wt% B and 0.1 wt% P, and IF steel with no B and P.

To verify the proposed constitutive model, a laboratory-scale hot-plate rolling experiment, together with three-dimensional finite element analysis coupled with the proposed model, has been performed. The capability of the proposed model was demonstrated through comparing predicted roll forces with measured values. A series of finite element simulations has then been carried out to study the variation in the distribution of the dynamically recrystallized volume fraction in the deformed workpiece by changing the rolling temperature and reduction ratio.

Good agreement was obtained between the predicted roll forces and experimental measurements for two IF steels. The roll force of IF steel with P and B components was 11.6 per cent larger than that of IF steel without them since dynamic recrystallization was delayed owing to the alloying elements. It has been found that, as the reduction ratio increases, the effect of those alloys on the volume fraction of dynamic recrystallization becomes more dominant and leads to considerable differences between the roll force of the steels.
Development of a product audit tool
Authors: Moultrie J , Clarkson P J , Probert D R
Published: October 2006

The creation of new products that satisfy both the needs of customers and of the company is widely acknowledged as an important contributor to a firm's ongoing success. In principle, the design process, as part of the wider new product development (NPD) process, should result in products that are ‘well designed’, but what does a well-designed product look like? This paper presents a tool to enable a design team to evaluate their products against a range of criteria, with a view to targeting design improvements. This ‘product audit’ tool is based on literature and has been iteratively developed using a mixed research approach, including detailed exploratory cases and application in action research mode. Previous assessment tools have tackled a narrow set of product issues, such as usability. This tool addresses the ‘whole product’ and captures aspects of product design in a concise and usable form. The product audit does not seek to be a benchmarking tool. Aspects such as novelty, desirability, usability, and producibility are expanded as simple checklists, to enable perceptions towards product characteristics to be assessed. This novel assessment tool encourages greater consideration of design issues within the wider context of NPD. By focusing attention on the tangible output of the design process ’ the product ’ practitioners are better able to understand the way in which design decisions influence product usability, desirability, and producibility. Case evidence confirms both the value and originality of this tool.
A new computer vision algorithm for the extraction of straight and curved features of two-dimensional products
Authors: Alshennawy A A , Gadelmawla E S , Elewa I M , Koura M M
Published: October 2006

Shape recognition is an important task in the field of computer vision. Many algorithms were developed to extract features from captured images of valuable objects. The traditional polygonal approximation algorithm (PAA) is a well-known algorithm in shape analysis for digital image processing and pattern recognition. The main objective of this algorithm is to convert a set of connected points in digitized images into a list of fitted lines, which represent a two-dimensional polygon. The main problem with this algorithm is that it lacks the ability to extract curved objects from the digitized images. In this paper, a new algorithm called an enhanced polygonal approximation algorithm (EPAA) is developed, based on the PAA, to extract both straight and curved features from digitized images of two-dimensional products. The EPAA is capable of classifying line and arc segments as well as circles. A description of the EPAA and an example of its application in the field of production engineering are presented.
Prediction of temperature and velocity distributions during hot rolling using finite elements and neural network
Authors: Serajzadeh S
Published: October 2006

Temperature and velocity distributions during hot strip rolling of a low-alloy steel are determined using a finite element method together with a neural network model. The finite element method is utilized to solve the governing equations of heat conduction and plastic deformation; at the same time a neural network model is employed for assessing flow stress of the metal being deformed. In this way, the effects of temperature, strain, and strain rate on flow stress could be included in the finite element analysis. In order to examine validity of the mathematical model, laboratory hot rolling experiments are carried out where the surface temperature and roll force are recorded. Comparison between the experimental and the predicted results shows a good consistency.
Investigating mechanical anisotropy and end-of-vector effect in laser-sintered nylon parts
Authors: Ajoku U , Saleh N , Hopkinson N , Hague R , Erasenthiran P
Published: October 2006

A study investigating the effects of part-build orientation in the laser sintering process is presented. The investigation uses tensile, flexural, and compression testing methods to assess the changes in the mechanical properties of laser-sintered nylon-12 parts. The test parts were built in the x, y, and z orientations with the x axis parallel to the direction of the laser scanning, the y axis perpendicular to the direction laser of scanning, and the z axis in the direction of powder layers. The results from the tests show that the build orientation of the parts has an effect on the mechanical properties produced. The tensile tests show a maximum difference of 16 per cent and 11.2 per cent in strength and modulus respectively for parts built in the x, y, and z axes. The flexural tests show a 9.4 per cent and 7 per cent maximum difference in strength and modulus respectively for the parts produced in the x, y, and z axes. For the compressive tests, there is a 3.4 per cent and 13.4 per cent maximum difference in strength and modulus respectively for the parts produced in the x, y, and z axes. A statistical analysis of the results obtained highlights the presence of anisotropy in tensile and compression parts owing to their build orientation in the laser sintering machine. The test parts built in the x axis orientation showed the highest strength and modulus values while the parts built in the z axis orientation showed poor strength and modulus values. However, this is not the case for the flexural test parts, which show the highest strength and modulus values are from those built in the y axis orientation. Analysis has shown that this is due to the end-of-vector effect, which is most prominent in the y axis orientation. This effect should always be considered during laser sintering, when mechanical integrity is vital.
Multiscale simulation on nanometric cutting of single crystal copper
Authors: Sun Xizhi , Chen Shijin , Cheng Kai , Huo Dehong , Chu Wenjiang
Published: October 2006

Molecular dynamics (MD) simulation and finite element (FE) method have been successfully applied in the simulation of the machining process, but the two methods have their own limitations. For example, the MD simulation can only explain the phenomena occurring at nanometric scale because of the computational cost and nanoscale, while the FE method is suited to model meso-macroscale machining and to simulate macro parameters such as the temperature in cutting zone, the stress/strain distribution, and cutting forces. With the successful application of multiscale simulation in many research fields, the multiscale simulation of the machining process is becoming possible in relation to the machined surface generation including the surface roughness, residual stress, microhardness, microstructure, and fatigue. Based on the quasicontinuum (QC) method, this paper presents the multiscale simulation of nanometric cutting of crystal copper to demonstrate that a combined MD—FE technique can be applied to a multiscale simulation of the machining process. The study shows that the multiscale simulation is feasible, not withstanding that there is still more work needing to be done to make the multiscale simulation more practical.
Characteristics of a diffusion absorption refrigerator driven by the waste heat from engine exhaust
Authors: Lin L , Wang Y , Al-Shemmeri T , Zeng S , Huang J , He Y , Huang X , Li S , Yang J
Published: October 2006

The characteristics of a diffusion absorption refrigerator driven by the waste heat from a diesel engine exhaust were investigated. The heating unit of the diffusion absorption refrigerator was modified to be able to utilize the waste heat from engine exhaust. A series of tests were conducted including the original refrigerator driven by the alternating current (AC) power, direct current (DC) power, liquid petroleum gas (LPG), and the waste heat from a diesel engine exhaust gas. The performances of the modified refrigerator driven by the waste heat from engine exhaust were compared with that of original performances of the refrigerator driven by AC, DC, and LPG. The results showed that the performances of the refrigerator driven by engine exhaust were better than that of the original refrigerator driven by AC and DC power. The results showed that the exhaust heat from diesel engine is an applicable, attractive energy resource for diffusion absorption refrigerator.
Designing a thermoelectrically powered wireless sensor network for monitoring aluminium smelters
Authors: Schneider M. H. , Evans J. W. , Wright P. K. , Ziegler D
Published: October 2006

Aluminium production cells, Hall-Héroult ‘potlines’, are inefficient and inadequately outfitted with sensors, mostly due to safety concerns with sensor wires between pots, possible interference with existing hardware, high installation costs, and the lack of an easily accessible, maintenance-free, continuous power source for the sensors. A tested solution to accurately measure various process parameters via wireless sensing technology, using either the cell's exhaust heat or steel shell as a thermoelectric power source is presented. Early experiments at Eastalco indicated that the motes, with a few modifications, will be able to operate reliably under industrial conditions, successfully transmitting radio packets through the plants' strong magnetic fields at distances of over 30 m. This article describes the successful testing of wireless measurements of cell parameters, discusses the energy-scavenging thermoelectric power sources and their electronics, and describes the future plans. The authors work is being carried out in conjunction with Alcoa in hopes of improving cell efficiency through better instrumentation.
Research on low cavitation in water hydraulic two-stage throttle poppet valve
Authors: Nie Songlin , Huang Guohe , Li Yongping , Yang Yousheng , Zhu Yuquan
Published: October 2006

Cavitation has important effects on the performances and lifespan of water hydraulic control valve, such as degrading efficiency, intense noise, and severe vibration. Two-stage throttle valve is a practicable configuration to mitigate cavitation, which is extensively used in water hydraulic pressure relief valves and throttle valves. The pressure distribution inside a medium chamber located between two throttles of a two-stage throttle valve is investigated through numerical simulations. The effects of the passage area ratio of the two throttles and the inlet and outlet pressures on the pressure inside the medium chamber are examined. The simulation results indicate that (a) the pressure inside the medium chamber is not constant, (b) the locations of maximum and minimum pressures inside the medium chamber are both fixed, which will not vary with the passage area ratio or the inlet and outlet pressures, and (c) the ratio of the pressure drop across the front throttle to the total pressure drop across the two-stage throttle valve is nearly constant. The critical cavitation index of the two-stage throttle valve is then established. A semiempirical design criterion is obtained for the water hydraulic two-stage throttle valve. The correlation between the critical cavitation index and the passage area ratio of the two throttles is investigated. Relevant validation experiments are conducted at a custom-manufactured testing apparatus. The experimental results are consistent with the simulated ones. Further analyses indicate that (a) the large backpressure can improve not only the anti-cavitation capability but also the total load rigidity of the water hydraulic two-stage throttle valve, (b) an appropriate passage area ratio will be beneficial for improving the anti-cavitation capability of the water hydraulic two-stage throttle valve, and (c) the water hydraulic two-stage throttle valve with a passage area ratio of 0.6 would have the best anti-cavitation performance with the lowest risk of cavitation.
Revenue Management Through Dynamic Cross Selling in E-Commerce Retailing
Authors: Netessine Serguei , Savin Sergei , Xiao Wenqiang
Published: October 2006

We consider the problem of dynamically cross-selling products (e.g., books) or services (e.g., travel reservations) in the e-commerce setting. In particular, we look at a company that faces a stream of stochastic customer arrivals and may offer each customer a choice between the requested product and a package containing the requested product as well as another product, what we call a “packaging complement.” Given consumer preferences and product inventories, we analyze two issues: (1) how to select packaging complements, and (2) how to price product packages to maximize profits.

We formulate the cross-selling problem as a stochastic dynamic program blended with combinatorial optimization. We demonstrate the state-dependent and dynamic nature of the optimal package selection problem and derive the structural properties of the dynamic pricing problem. In particular, we focus on two practical business settings: with (the Emergency Replenishment Model) and without (the Lost-Sales Model) the possibility of inventory replenishment in the case of a product stockout. For the Emergency Replenishment Model, we establish that the problem is separable in the initial inventory of all products, and hence the dimensionality of the dynamic program can be significantly reduced. For both models, we suggest several packaging/pricing heuristics and test their effectiveness numerically.
Models of the Spiral-Down Effect in Revenue Management
Authors: Cooper William L. , Homem-de-Mello Tito , Kleywegt Anton J.
Published: October 2006

The spiral-down effect occurs when incorrect assumptions about customer behavior cause high-fare ticket sales, protection levels, and revenues to systematically decrease over time. If an airline decides how many seats to protect for sale at a high fare based on past high-fare sales, while neglecting to account for the fact that availability of low-fare tickets will reduce high-fare sales, then high-fare sales will decrease, resulting in lower future estimates of high-fare demand. This subsequently yields lower protection levels for high-fare tickets, greater availability of low-fare tickets, and even lower high-fare ticket sales. The pattern continues, resulting in a so-called spiral down. We develop a mathematical framework to analyze the process by which airlines forecast demand and optimize booking controls over a sequence of flights. Within the framework, we give conditions under which spiral down occurs.
Controlling Inventories in Divergent Supply Chains with Advance-Order Information
Authors: Marklund Johan
Published: October 2006

This paper considers a generic one-warehouse multiple-retailer inventory system under continuous review, where customers provide perfect advance-order information. More specifically, each customer order entails a due date specifying when the customer wants the item delivered. The information is perfect in the sense that a placed order cannot be revised. With the intent of using the advance-order information fully throughout the supply chain, each installation replenishes its stock using order base-stock policies (see Hariharan and Zipkin 1995). As for stock allocation, the presence of advance-order information at the central warehouse raises important questions regarding when reservations should be made for different retailers, i.e., how to make best use of the available temporal information to allocate items to retailers. Exact and approximate cost evaluation techniques are presented for the general case, the general reservation policy, as well as for the two special cases of reserving as early as possible, the complete reservation policy, and as late as possible, the last-minute allocation policy. A numerical study illustrates the performance of the proposed heuristics and provides insights on the value of using advance-order information in supply chain inventory control.
Optimizing Chemotherapy Scheduling Using Local Search Heuristics
Authors: Agur Zvia , Hassin Refael , Levy Sigal
Published: October 2006

We develop a method for computing efficient patient-specific drug protocols. Using this method, we identify two general categories of anticancer drug protocols, depending on the temporal cycle parameters of the host and cancer cells: a one-time intensive treatment, or a series of nonintensive treatments. Our method is based on a theoretical and experimental work showing that treatment efficacy can be improved by determining the dosing frequency on the drug-susceptible target and host cell-cycle parameters. Simulating the patient's pharmaco-dynamics in a simple model for cell population growth, we calculate the number of drug susceptible cells at every moment of therapy. Local search heuristics are then used to conduct a search for the desired solution, as defined by our criteria. These criteria include the patient's state at the end of a predetermined time period, the number of cancer and host cells at the end of treatment, and the time to the patient's cure. The process suggested here does not depend on the exact biological assumptions of the model, thus enabling its use in a more complex description of the system. We test three solution methods. Simulated annealing is compared to threshold acceptance and old bachelor acceptance, which are less known variants to this method. The conclusions concerning the three approximation methods are that good results can be achieved by choosing the proper parameters for each of the methods, but the computational effort required for achieving good results is much greater in simulated annealing than in the other methods. Also, a large number of iterations does not guarantee better solution quality, and resources would be better used in several short searches with different parameter values than in one long search.
A Continuum Model for a Re-entrant Factory
Authors: Armbruster Dieter , Marthaler Daniel E. , Ringhofer Christian , Kempf Karl , Jo Tae-Chang
Published: October 2006

High-volume, multistage continuous production flow through a re-entrant factory is modeled through a conservation law for a continuous-density variable on a continuous-production line augmented by a state equation for the speed of the production along the production line. The resulting nonlinear, nonlocal hyperbolic conservation law allows fast and accurate simulations. Little's law is built into the model. It is argued that the state equation for a re-entrant factory should be nonlinear. Comparisons of simulations of the partial differential equation (PDE) model and discrete-event simulations are presented. A general analysis of the model shows that for any nonlinear state equation there exist two steady states of production below a critical start rate: A high-volume, high-throughput time state and a low-volume, low-throughput time state. The stability of the low-volume state is proved. Output is controlled by adjusting the start rate to a changed demand rate. Two linear factories and a re-entrant factory, each one modeled by a hyperbolic conservation law, are linked to provide proof of concept for efficient supply chain simulations. Instantaneous density and flux through the supply chain as well as work in progress (WIP) and output as a function of time are presented. Extensions to include multiple product flows and preference rules for products and dispatch rules for re-entrant choices are discussed.
Endoscopic orbital decompression
Authors: Metson Ralph , Dallow Richard L. , Shore John W.
Published: October 2006

Exophthalmos from Graves' disease can result in visual disability and cosmetic deformity. Surgical treatment of this disorder is now possible through an intranasal endoscopic approach that allows removal of the medial orbital wall and floor without an external incision. Endoscopic orbital decompression was performed on 22 orbits in 14 patients for treatment of progressive exophthalmos. Local anesthesia was used in five cases. Sixteen procedures involved a concurrent lateral orbital decompression performed through an external approach. There were no intraoperative or postoperative complications. Visual acuity remained stable or improved in all cases. Proptosis was reduced an average of 3.2 ± 1.1 mm (range 2 to 4.5 mm) by endoscopic decompression alone. When a lateral decompression was also performed, proptosis was reduced by an additional 2.4 mm, for an average improvement of 5.6 ± 1.7 mm (range 2 to 8 mm). Endoscopic orbital decompression appears to be a safe technique for the treatment of exophthalmos that can be performed effectively with the patient under general or local anesthesia.
Middle ear mucosal inflammation: An in vivo model
Authors: Chan Kenny H. , Swarts J. Douglas , Tan Lingshi
Published: October 2006

The inflammatory process underlies the pathogenesis of otitis media (OM). Although knowledge concerning this common childhood disease continues to accumulate, most of the basic science research is based on in vitro or ex vivo methodologies. Magnetic resonance imaging (MRI), although lauded for its ability to image soft tissue, is often neglected as a research tool providing real‐time in vivo information. This study attempts to assess experimental middle ear (ME) inflammation using MRI. The vasoactive effects of histamine and its interaction with antihistamines and a glucocorticoid were evaluated. Histamine was chosen because it is one of the naturally occurring inflammatory mediators. The antagonists were selected on the basis of their antihistaminic and vasoactive effects, respectively. Certainly there is substantial clinical interest in these agents because their efficacy for the treatment of OM is still being debated. The chinchilla model was chosen since it is one of the best characterized species in the study of OM.

The three parts of the study are as follows: the effects of histamine on chinchilla ME mucosa; histamine challenge following pretreatment using hydroxyzine hydrochloride (H1 antagonist), ranitidine chloride (H2 antagonist), and the combination; and histamine challenge following pretreatment with dexamethasone. Sequential T1‐weighted spin‐echo (SE) MRI was used to detect extravasation of gadolinium‐diethylenetriaminepentaacetic acid (Gd‐DTPA) into the middle ear effusion (MEE). The results indicate that the vasoactive effects of histamine are dose‐related and can be assessed across a wide spectrum of histamine dosages inclusive of the human MEE levels. The H1 antagonist alone, or in combination with the H2 antagonist, was able to prevent the increased vascular permeability induced by histamine. When used alone, the H2 antagonist did not abolish the effects of histamine. The vasoactive effects of histamine were also ameliorated by pretreatment with a glucocorticoid.

These findings indicate the utility of MRI for assessing mucosal inflammation in a real‐time manner rather than as an accumulation of events. This study also validates the efficacy of an H1 antagonist and a glucocorticoid in counteracting the vasoactive effects of histamine. This methodology may be suited for evaluating the effects of other classes of antiinflammatory mediators.
The risk to olfaction from nasal surgery
Authors: Kimmelman Charles P.
Published: October 2006

Implicit in all types of nasal surgery is the potential for worsening of olfactory function. Not only can injury occur to the delicate olfactory neuroepithelium itself, but also more indirect disturbances are engendered by pharmacologic agents, distortions of intranasal anatomy, persistent mucosal edema or crusts, and other processes.

This study examined 93 patients undergoing various types of nasal surgery, including ethmoidectomy, polypectomy, Caldwell‐Luc procedure, open reduction of nasal fracture, closed reduction of nasal fracture, rhinoplasty, and septoplasty. Factors considered as contributing to loss of olfactory acuity were age, gender, use of general anesthesia, and type of operation. The University of Pennsylvania Smell Identification Test (UPSIT), a 40‐item, microencapsulated scratch‐and‐sniff procedure, was used to ascertain olfactory ability.

Sixty‐one patients (66%) had either improved or unchanged UPSIT scores after surgery; the remaining 32 patients (34%) had a decline in score. One patient (1%) became anosmic. Statistical treatment of outcome data using analysis of covariance with repeated measures showed no effect of age, gender, type of operation, or anesthetic.
Cochlear polyamines: Markers of otitis media‐induced cochlear damage
Authors: Naguib Maged B. , Hunter Robert E. , Henley Charles M.
Published: October 2006

High‐performance liquid chromatography (HPLC) set to the femtoliter sensitivity level was used to identify and quantify the polyamines spermidine and spermine as well as the diamine putrescine in the different tissues of the inner ears of guinea pigs with experimentally induced otitis media. The tissues examined were the lateral wall (stria vascularis and the spiral ligament), the organ of Corti, and the cochlear nerve. The difference in polyamine profile in the different tissues of the control noninfected guinea pigs suggests a relation to the particular function of each of these tissues. The difference in polyamine profile in infected different inner ear tissues compared to controls encourages the assumption that the polyamines may be involved in a repair process of the inner ear after injury and that they may be considered as biochemical markers for inner ear damage secondary to acute otitis media.
Lack of synergistic association between human papillomavirus and ras gene point mutation in laryngeal carcinomas
Authors: Shidara Kouichi , Suzuki Takeshi , Hara Futoshi , Nakajima Takashi
Published: October 2006

The spectrum of human papillomavirus (HPV) subtypes in laryngeal carcinomas was investigated by combined polymerase chain reaction (PCR) and restriction fragment length polymorphism analysis. HPV DNA was detected in 11 (24%) of 45 cases, including HPV 16 in 9 cases and HPV 18 in 2 cases. Other HPV subtypes commonly found in the female genital organs were not detected. In addition, the point mutation of codons 12 and 13 in c‐Ki‐ras‐2, c‐Ha‐ras‐1, and N‐ras genes was studied by the PCR‐single‐strand conformational polymorphism (SSCP) method. Of 45 cases tested, only 1 had a point mutation of c‐Ki‐ras‐2 gene at codon 12. These results indicate that the incidence of ras gene point mutation is uncommon and that the synergistic effect of HPV infection and ras gene activation in laryngeal carcinogenesis is probably rare.
Nasal cavity dimensions in the newborn measured by acoustic reflections
Authors: Pedersen O. F. , Hilberg O. , Berkowitz R. , Yamagiwa M.
Published: October 2006

The acoustic refections technique was used to measure nasal cavity dimensions in 27 newborns. The results were expressed in terms of curves describing cross‐sectional area as a function of the distance into the nose. From these curves, a mean curve with 95% confidence limits, nasal cavity volumes between the nostril and 4.5 cm into the nasal cavity (V45 = 1.05 (0.24) cm3), the cross‐sectional area at the narrowest site (Amin = 0.114 (0.033) cm2), and the distance from the nostril to Amin, (DAmin = 1.14 (0.47) cm), expressed as mean and SD were calculated. There was a weak correlation between Amin and length and weight at birth, but otherwise nasal cavity dimensions did not correlate with sex, race, birth weight, birth length, head circumference, or duration of gestation. Comparison of the curves from the newborns with curves from adults showed a facial growth in vertical/transverse directions (area) of 600% and anterior/posterior directions of 120%. The technique of acoustic rhinometry is noninvasive, and can be performed rapidly, and is therefore eminently suitable for pediatric application. Further investigations are needed to demonstrate the value as a diagnostic tool in pathological cases.
Effects of vestibular rehabilitation and social reinforcement on recovery following ablative vestibular surgery
Authors: Mruzek Maria , Barin Kamran , Nichols Deborah S. , Burnett Carolyn N. , Welling D. Bradley
Published: October 2006

This study investigated the relative effects of vestibular rehabilitation (VR) and social reinforcement (SR) on recovery following ablative vestibular surgery. Twenty‐four subjects were randomly assigned to three treatment groups of either VR with SR, VR without SR, or general range of motion (ROM) exercises with SR. Outcome measures included equilibrium scores in dynamic posturography, asymmetry index in rotation testing, motion sensitivity quotient (MSQ), and dizziness handicap inventory (DHI). A multiple comparison of the overall outcome measures showed no significant differences in group performance over an 8‐week period. When individual outcome measures were compared, MSQ and DHI results at the end of the 8‐week treatment period revealed less motion sensitivity and dizziness handicap in groups who received VR, with or without SR, as compared with the group who received ROM exercises. These results suggest that after a vestibular injury most patients can effectively utilize central compensation mechanisms to recover from such an injury, regardless of the type of therapeutic intervention used. On the other hand, the reduction in motion sensitivity and dizziness handicap for patients who received VR could indicate a more rapid and complete recovery for these patients. This investigation is continuing as a long‐term follow‐up study to determine whether there are any long‐term benefits in participating in a VR program.
Acoustic schwannoma and pregnancy: A DNA flow cytometric, steroid hormone receptor, and proliferation marker study
Authors: Beatty Charles W. , Scheithauer Bernd W. , Katzmann Jerry A. , Roche Patrick C. , Kjeldahl Klint S. , Ebersold Michael J.
Published: October 2006

For a long time, it has been speculated that pregnancy stimulates the growth of acoustic schwannomas. To test this hypothesis, immunohistochemical stains for estrogen receptor, progesterone receptor, and proliferating cell nuclear antigen (PCNA) were performed. Flow cytometric studies for DNA ploidy and S‐phase fraction determinations were also performed. The study subjects included 6 female patients with unilateral acoustic tumors; at the time of tumor removal, 1 woman was pregnant and the other 5 women were 2 to 10 months postpartum. The age‐sex‐matched control group consisted of 6 men and 12 nonpregnant women, all with acoustic schwannomas similar in size to those of the study group. The study found no statistically significant association between the presence or quantity of estrogen or progesterone receptors and pregnancy, DNA ploidy, proliferation indices, or clinical data. Based on PCNA indices, large tumors tended to be less “biologically active” than small lesions (P<.01). The authors concluded that pregnancy does not significantly stimulate the cellular growth of acoustic schwannomas.
Liposarcomas of the larynx and hypopharynx: A clinicopathologic study of eight new cases and a review of the literature
Authors: Wenig Bruce M. , Heffher Dennis K.
Published: October 2006

Laryngeal and hypopharyngeal liposarcomas were studied in seven men and one woman. Patient age ranged from 25 to 81 years, with a median of 64 years. Symptoms included dysphagia, airway obstruction, and the sensation of a foreign body in the back of the throat. Histologically, seven of the tumors were of the biologically favorable types, either representing well‐differentiated (lipoma‐like) liposarcomas or myxoid liposarcomas. One tumor was a pleomorphic liposarcoma. Six of the eight patients had one or more episodes of recurrent tumor.

Surgery is the treatment of choice and can include conservative (organ‐sparing) procedures. However, to eradicate the tumor completely and thereby prevent recurrent disease, open surgical approaches (i.e., lateral pharyngotomy), rather than endoscopic techniques should be employed. The morbidity rate for laryngeal and hypopharyngeal liposarcomas is high because these tumors tend to recur over extended periods of time. In this study, however, there were no instances of metastatic disease, and no deaths were attributed to liposarcoma. Prospectively, laryngeal and hypopharyngeal well‐differentiated (lipoma‐like) liposarcoma is a difficult clinical and histopathologic diagnosis to establish. Often, this diagnosis is made only after one or more episodes of recurrent disease.
Measurements of cross‐sectional area of the nasal cavity by acoustic rhinometry and CT scanning
Authors: Min Yang‐Gi , Jang Yong Ju
Published: October 2006

The authors aimed to evaluate the validity and characteristics of acoustic rhinometric tests by comparing the results with those of computed tomography (CT) of the nasal cavity. Cross‐sectional areas along the nasal cavity were measured by acoustic rhinometry (AR) and CT of the nasal cavity in 30 normal subjects.

Cross‐sectional areas measured by each technique showed a statistically significant correlation. The two measurements showed a better linear correlation in the anterior part of the nasal cavity up to 24 mm from the nostril than in the posterior part of the nasal cavity beyond that point. Mean cross‐sectional areas measured by AR were constantly less than those measured by CT of the nasal cavity up to 33 mm from the nostril, whereas areas measured by AR were greater than those measured by CT scans beyond that point.
Coping with ovarian cancer risk: The moderating effects of perceived control on coping and adjustment
Authors: Fang Carolyn Y. , Daly Mary B. , Miller Suzanne M. , Zerr Tana , Malick John , Engstrom Paul
Published: October 2006

Objective. Although perceived control and coping have been studied across various health conditions, these relationships have been less well studied in the context of coping with cancer risk over time. The present study was a longitudinal study of the effects of perceived control and problem‐focused coping on changes in psychological adjustment and behavioural outcomes among women at increased risk for ovarian cancer.

Design and methods. Eighty women enrolled in a familial cancer risk assessment programme participated in this study. Assessments of problem‐focused coping, perceived control and distress were collected upon entry into the programme and again at 3‐month follow‐up. Behavioural adherence to screening during the 12‐month period following programme entry was obtained from clinic records.

Results. Using hierarchical regression analysis, we observed a significant interaction between perceived control and problem‐focused coping for psychological distress, β = 0.94, p <.05. Specifically, problem‐focused coping was associated with increasing distress over time among women who perceived high control. A significant control by coping interaction was also observed for behavioural adherence to pelvic ultrasound and CA125 screening, such that women who perceived high control and utilized problem‐focused coping were less likely to undergo screening.

Conclusions. Under conditions of high perceived control, problem‐focused coping was associated with increasing distress as well as poorer behavioural adherence. Thus, perceived control and problem‐focused coping may not always yield positive psychological or behavioural health outcomes. These findings contribute to a greater understanding of how problem‐focused coping and perceived control may influence the course of adjustment to cancer risk over time.
Sample size for regression analyses of theory of planned behaviour studies: Case of prescribing in general practice
Authors: Rashidian Arash , Miles Jeremy , Russell Daphne , Russell Ian
Published: October 2006

Objectives. Interest has been growing in the use of the theory of planned behaviour (TBP) in health services research. The sample sizes range from less than 50 to more than 750 in published TPB studies without sample size calculations. We estimate the sample size for a multi‐stage random survey of prescribing intention and actual prescribing for asthma in British general practice. To our knowledge, this is the first systematic attempt to determine sample size for a TPB survey.

Methods. We use two different approaches: reported values of regression models' goodness‐of‐fit (the λ method) and zero‐order correlations (the variance inflation factor or VIF method). Intra‐cluster correlation coefficient (ICC) is estimated and a socioeconomic variable is used for stratification. We perform sensitivity analysis to estimate the effects of our decisions on final sample size.

Results. The VIF method is more sensitive to the requirements of a TPB study. Given a correlation of .25 between intention and behaviour, and of .4 between intention and perceived behavioural control, the proposed sample size is 148. We estimate the ICC for asthma prescribing to be around 0.07. If 10 general practitioners were sampled per cluster, the sample size would be 242.

Conclusions. It is feasible to perform sophisticated sample size calculations for a TPB study. The VIF is the appropriate method. Our approach can be used with adjustments in other settings and for other regression models.
Mind the gap…in intelligence: Re‐examining the relationship between inequality and health
Authors: Kanazawa Satoshi
Published: October 2006

Wilkinson contends that economic inequality reduces the health and life expectancy of the whole population but his argument does not make sense within its own evolutionary framework. Recent evolutionary psychological theory suggests that the human brain, adapted to the ancestral environment, has difficulty comprehending and dealing with entities and situations that did not exist in the ancestral environment and that general intelligence evolved as a domain‐specific adaptation to solve evolutionarily novel problems. Since most dangers to health in the contemporary society are evolutionarily novel, it follows that more intelligent individuals are better able to recognize and deal with such dangers and live longer. Consistent with the theory, the macro‐level analyses show that income inequality and economic development have no effect on life expectancy at birth, infant mortality and age‐specific mortality net of average intelligence quotient (IQ) in 126 countries. They also show that an average IQ has a very large and significant effect on population health but not in the evolutionarily familiar sub‐Saharan Africa. At the micro level, the General Social Survey data show that, while both income and intelligence have independent positive effects on self‐reported health, intelligence has a stronger effect than income. The data collectively suggest that individuals in wealthier and more egalitarian societies live longer and stay healthier, not because they are wealthier or more egalitarian but because they are more intelligent.
Information, social support and anxiety before gastrointestinal endoscopy
Authors: Eberhardt Judith , van Wersch Anna , van Schaik Paul , Cann Paul
Published: October 2006

Objectives. To examine Lazarus and Folkman's (1984) stress theory regarding the effects of the stress mediators information and perceived social support on anxiety (as the stress response) regarding gastrointestinal (GI) endoscopy (as the stressor) in male and female patients of various age groups.

Design. Non‐experimental design.

Methods. Structured interviews were conducted with 113 hospital out‐patients about to undergo GI endoscopy. Participants indicated their perceptions of how much support and how much clear and useful information they had received from both their general practitioner (GP) and a patient information leaflet developed in collaboration with health psychologists as well as their perceptions of how much social support they had obtained from other patients, family and friends. Anxiety was measured with a population‐specific trait and state adaptation of the Hospital anxiety and depression scale (HADS‐A).

Results. Psychometric exploration of the HADS‐A revealed a single general anxiety factor. The reliability of this factor was high, with Cronbach's α = 0.91. The majority of the sample experienced high anxiety levels. Gender, but not age, differences emerged, showing females to be more anxious than males, F (1, 84) = 5.68, p <.05. A regression model built on stress theory was tested, with anxiety as the dependent variable and 11 predictor variables. The model was significant with R2 = 0.452, F (11, 47) = 3.522 and p = 0.001.

Conclusions. The clarity, but not the amount, of information and social support from important others, but not GPs, were both mediating the stress experience of the patients by reducing their perceived anxiety.
Predicting self‐efficacy using illness perception components: A patient survey
Authors: Lau‐Walker Margaret
Published: October 2006

Objectives. To assess the measures of illness representation components in predicting measures of self‐efficacy in patients with coronary heart disease.

Design. A longitudinal design was adopted with predictor variables and dependent variables (general self‐efficacy, diet self‐efficacy and exercise self‐efficacy) measured twice while participants were in hospital and 9 months following discharge. Change scores of the predictor variables can be calculated and dependent variables at baseline can be controlled.

Method. A cohort sample of 300 patients admitted to hospital with coronary heart disease were given the questionnaire measuring their illness perception (illness representation components: identity, consequences, timeline and control/cure and outcome expectation for diet and exercise); self‐efficacy (general, diet and exercise self‐efficacy measures), demographic and illness characteristics and attendance on a cardiac rehabilitation programme. The patients were asked to complete the questionnaire in hospital before discharge following their cardiac diagnosis, and again, 9 months later, when participants were expected to be functioning independently of any rehabilitation programme.

Results. Demographic and illness characteristics were found to have a more significant relationship with illness representation components than with specific self‐efficacy. The relationship between illness representation components and specific self‐efficacy changes overtime, consequence and timeline were significantly related to self‐efficacy measures initially; however, symptom and control/cure were the variables that were significantly related to self‐efficacy measures 9 months later. After statistically controlling individuals' baseline self‐efficacy measures, demographic and illness characteristic effects, symptom and control/cure were found to make significant contributions to exercise and diet self‐efficacy, respectively, 9 months later.

Conclusion. A significant relationship exists between illness representation and self‐efficacy. There is potential to integrate both approaches to the assessment of psychosocial factors to provide effective individualized care in cardiac rehabilitation.
An electronic diary assessment of the effects of distraction and attentional focusing on pain intensity in chronic low back pain patients
Authors: Roelofs Jeffrey , Peters Madelon L. , Patijn Jacob , Schouten Erik G. W. , Vlaeyen Johan W. S.
Published: October 2006

Objective.The present study examined the effects of a manipulation of attention to pain (i.e. attentional focusing vs. distraction) on pain intensity in daily life of patients with chronic low back pain. It was hypothesized that attentional focusing would lead to decreased pain intensity in high pain fearful individuals, whereas distraction from pain would be associated with decreased pain intensity in low pain fearful individuals.

Design.An experience sampling methodology was used to examine the effects of a manipulation of attention to pain on pain intensity in daily life of pain patients.

Methods.A total number of 38 patients with chronic low back pain participated in this study and carried a palmtop computer for 2 weeks. During this period, patients were ‘beeped’ 8 times a day to complete diary questions. On certain days, instructions to either attend to or distract from pain were given.

Results.Multi‐level analyses showed that attentional focusing was not associated with decreased pain intensity in high pain fearful individuals and that distraction did not lead to decreased pain intensity in low pain fearful individuals. The manipulations in isolation neither influenced pain intensity. The manipulation check was generally weak.

Conclusion.A manipulation of attention to pain in daily life of patients with chronic low back pain proved difficult to accomplish. As the manipulation check was generally unsuccessful, no clear inferences about the underlying theory can be made. Future research within the field of pain treatments (e.g.in vivoexposure) might benefit greatly from electronic diary assessments studies.
A Review of Swedish Bearing Steel Manufacturing and Quality Assurance of Steel Products
Authors: Johansson TI , Lund TB , Ölund PLJ
Published: October 2006

The Swedish bearing steel industry dates back a century. Already in the early days, Swedish bearing steels were characterized by an exceptionally high quality due to the availability of pure iron ores that made it possible to produce bearing steels by the acid open-hearth processes. Development of the ladle furnace process using inductive stirring made it possible to use the much more flexible and cost effective electric arc melting process. The strive to produce ever better steel products has been strong, driven by increasing demands on final product performance. Developments in steel processing technology, process know-how, and understanding of the complex relationships governing steel cleanliness are worth noting. Methods used have undergone vast improvements in recent times and the development continues. The same situation is valid for the quality assurance methods employed in the manufacturing of steel products.