bluuebunny/crossref_metadata_2025_split huggingface dataset:
Free Jejunal Interposition following Pharyngolaryngectomy: Report on 25 Consecutive Cases
Authors: CHENG M.S. , CHEUNG W.Y. , HO C.M. 
Published: April 2004

Free jejunal interposition has become a common procedure for reconstruction of circumferential defects following pharyngolaryngectomy.Methods: Retrospective analysis of 25 consecutive free jejunal interposition grafts performed in the Department of Surgery, Kwong Wah Hospital between 1995 and 2002. The median age was 65 (range 45–74). There were 22 men and three women. The median follow up was 20 months. The most common site was the hypopharynx (n=17), followed by larynx (n=2), neopharynx (n=2), tongue base (n=2), recurrent carcinoma thyroid (n=1) and intractable gastritis post PLO secondary to radiotherapy (n=1). They were all either T3 or T4 tumours. Three patients had received prior radiotherapy as initial treatment or for another previous primary. Twenty patients received postoperative radiotherapy. The jejunum interposition grafts were harvested from the second or third arcade. Esophago‐jejunal and pharyngo‐jejunal anastomoses were performed in sequence and in the end to end manner. Sentinel loops were used to monitor flap viability in the majority of cases.Results: There was no peri‐operative mortality. Major complications include six anastomotic leakages treated conservatively, one delayed flap failure(1/25) due to infection and one post operative myocardial infarction. Donor site morbidity includes one intra‐abdominal haemorrhage due to slipped mesenteric ligatures and one jejuno‐jejunal anastomotic stricture. There was no fistula or stricture formation. Nineteen patients were available for assessment and 94% were able to maintain solid (11/18) and soft diet (7/18) at 1 year postoperatively. Voice rehabilitation includes electrolaryx (6), pneumatic devices (3) and Provox (5). Kaplan‐Meyer was used to estimate survival and the 1‐ and 3‐year survival rates were 70 and 46.9%, respectively. Nine patients died of loco‐regional recurrence; one with carotid blowout. One patient died of systemic metastases. Two patients succumbed to another aero‐digestive primary tumour and two to unrelated medical problem.Conclusion: In conclusion, the free jejunal interposition graft is a safe and predictable method of reconstruction following total pharyngolaryngectomy and expeditiously providing return of function in patients with late stage disease.
Proton magnetic resonance spectroscopy in corticobasal degeneration and progressive supranuclear palsy
Authors: Negoro Kiyoshi , Tada Yukiko , Ogasawara Jun‐ichi , Kawai Motoharu , Morimatsu Mitsunori , Hashida Masahiro , Yamauchi Syu‐ichi 
Published: April 2004

Background:  Corticobasal degeneration (CBD) and progressive supranuclear palsy (PSP) each have distinctive clinical features, but diagnosis is often uncertain. Our purpose was to evaluate whether localized, single‐voxel proton magnetic resonance spectroscopy (1H‐MRS) could distinguish between typical CBD and PSP patients.Methods:  The study included 10 patients with CBD, nine with PSP and eight age‐matched normal healthy subjects. A single‐voxel method of 8 cm3 (2 × 2 × 2 cm) was used for 1H‐MRS. The volume of interest was selected at the frontoparietal cortex and the lentiform nucleus.Results:  Patients with CBD had significantly reduced ratios of N‐acetylaspartate to choline‐containing compounds (NAA/Cho), N‐acetylaspartate to creatine and phosphocreatine (NAA/Cr) in the frontoparietal cortex and lentiform nucleus compared with the normal subjects. Patients with PSP had significantly reduced NAA/Cho and NAA/Cr ratios in the lentiform nucleus, but not in the frontoparietal cortex compared with normal subjects. There was a significant difference in the NAA/Cho in the frontoparietal lobe between CBD and PSP patients.Conclusion:  1H‐MRS may indicate different regional patterns of neuronal involvement in CBD and PSP. We suggest that this could be helpful in the differentiation and diagnostic evaluation of CBD and PSP patients.
Root resorption and its association with alterations in physical properties, mineral contents and resorption craters in human premolars following application of light and heavy controlled orthodontic forces
Authors: Darendeliler MA , Kharbanda OP , Chan EKM , Srivicharnkul P , Rex T , Swain MV , Jones AS , Petocz P 
Published: April 2004

Structured AbstractAuthors – Darendeliler MA, Kharbanda OP, Chan EKM, Srivicharnkul P, Rex T, Swain MV, Jones AS, Petocz PObjectives – To study the effect of different orthodontic force levels on cementum, investigating from the point of view of its physical properties, alterations in the mineral components, type and location of the resorption craters and the exploration in 3D of space.Design – In vivo human premolars subjected to heavy and light forces were employed for this study. After a period of movement they were analyzed for hardness and elasticity. Also, the mineral composition measuring Ca, P and F of the cementum root surface was investigated. A new method for volumetric analysis of resorption craters was developed.Results – There were no significant differences for hardness and elastic modulus between the light and heavy force groups and no significant effects for different tooth positions. Significant inter‐individual variation in the Ca, P and F concentrations was noted. Force‐related data showed that mean volume of the resorption crater in light‐force group was 3.49‐fold greater than the control group, and the heavy‐force group 11.59‐fold more than control group. The heavy force group had 3.31‐fold greater total resorption volume then light force group. Buccal cervical and lingual apical regions demonstrated significantly more resorption craters than the other regions. The 2D measurements were strongly correlated to 3D measurements.Conclusion – The application of light and heavy forces did not show any statistically significant differences in hardness and elastic modulus when compared with untreated teeth. The inconsistent increase or decrease of Ca, P and F contents between control and experimental teeth at sites of compression and tension were difficult to explain. There was more resorption by volume in the heavy force group as compared with the light group and controls. Our data also suggested that the high‐pressure zones might be more susceptible to resorption after 28 days of force application.
Economies of Scale in Empty Freight Car Distribution in Scheduled Railways
Authors: Joborn Martin , Crainic Teodor Gabriel , Gendreau Michel , Holmberg Kaj , Lundgren Jan T. 
Published: April 2004

In this paper, we consider empty freight car distribution in a scheduled railway system. We analyze the cost structure for the repositioning of empty cars, and conclude that the distribution cost shows an economy-of-scale behavior. In addition to the cost proportional to the number of cars sent from origin to destination, there is a cost related to car-handling operations at yards, which depends on the number of car groups that are handled. Thus, if we can find a transportation pattern in which fewer but larger groups of cars are built, the total distribution cost can be decreased. The objective of the paper is to propose an optimization model that explicitly takes this economy-of-scale effect into account. We use a time-dependent network to describe the possible car movements in time and space, and show how this network can be transformed into a network with fixed costs on links representing movements of cars with identical origin and destination terminals. The resulting optimization model is a capacitated network design model, where each capacity constraint limits the flow on several arcs. We describe a tabu heuristic for solving the model, and present computational results.
Real-Time Multivehicle Truckload Pickup and Delivery Problems
Authors: Yang Jian , Jaillet Patrick , Mahmassani Hani 
Published: April 2004

In this paper we formally introduce a generic real-time multivehicle truckload pickup and delivery problem. The problem includes the consideration of various costs associated with trucks' empty travel distances, jobs' delayed completion times, and job rejections. Although very simple, the problem captures most features of the operational problem of a real-world trucking fleet that dynamically moves truckloads between different sites according to customer requests that arrive continuously. We propose a mixed-integer programming formulation for the offline version of the problem. We then consider and compare five rolling horizon strategies for the real-time version. Two of the policies are based on a repeated reoptimization of various instances of the offline problem, while the others use simpler local (heuristic) rules. One of the reoptimization strategies is new, while the other strategies have recently been tested for similar real-time fleet management problems. The comparison of the policies is done under a general simulation framework. The analysis is systematic and considers varying traffic intensities, varying degrees of advance information, and varying degrees of flexibility for job-rejection decisions. The new reoptimization policy is shown to systematically outperform the others under all these conditions.
Development of the trabecular structure within the ulnar medial coronoid process of young dogs
Authors: Wolschrijn Claudia F. , Weijs Win A. 
Published: April 2004

AbstractThis study describes the timing of development of the trabecular structure of the ulnar medial coronoid process (MCP) in the dog. The right MCPs of nine healthy golden retrievers, aged 4 to 24 weeks, without signs of secondary joint disease were dissected and scanned with microcomputed tomography (micro‐CT) at a voxel size of 34 μm to determine histomorphometric parameters. Bone volume fraction and mean trabecular separation show a reciprocal pattern in time, reflecting an initial high bone density (and low trabecular separation), and then a sharp drop in density at 8–10 weeks, followed by a gradual increase to high values at 24 weeks. With a similar bone volume fraction as in young bone, the older bone shows thicker trabeculae and a more plate‐like structure. This is reflected in the much smaller number of trabeculae and the lower surface/volume ratio at higher age. An anisotropic structure of the trabeculae with an orientation in the direction of the proximodistal axis of the ulna is already present at 6 weeks after birth. This primary alignment was perpendicular to the humeroulnar articular surface, matching the direction of the compressive forces applied to the MCP by the humeral trochlea. The secondary alignment appeared at 13 weeks after birth and was directed along the craniocaudal axis of the MCP, toward the attachment of the anular ligament. In comparison with data from long bones and vertebrae, the findings of a high bone volume fraction and a well‐defined trabecular alignment at a very early age are remarkable. The high bone volume fraction is possibly a remnant of the fetal trabecular structure, as dogs are relatively immature at birth compared to other animals. Soon after the start of steady locomotion, the trabecular structure changes into a more mature‐like structure. The early trabecular alignment is possibly a reflection of the early load‐bearing function of the MCP in the elbow joint. Anat Rec Part A 278A:514–519, 2004. © 2004 Wiley‐Liss, Inc.
Noninvasive analyses of polyunsaturated fatty acids in human oral mucosa in vivo by Fourier‐transform infrared spectroscopy
Authors: Yoshida Satoshi , Yoshida Hiroshi 
Published: April 2004

AbstractThe aim of this study was to develop a noninvasive method to observe polyunsaturated fatty acids (PUFAs) behavior in the human body using Fourier transform infrared spectroscopy. For the noninvasive measurement of human oral mucosa, we have used infrared spectroscopy with a suitable attachment for an in vivo attenuated total reflectance system. The fatty acid contents in the tissues were determined by gas‐chromatography mass‐spectrometry after methylation. The alkene C‐H stretching vibrations of unsaturated fatty acids in dietary oils showed infrared absorption bands with various peak positions and intensities at around 3010 cm‐1 depending on the extent of unsaturation and their species. The diurnal fluctuation of the alkene peak position of oral mucosa suggested that the contents of PUFAs were increased gradually in the early afternoon, and these data were supported by the direct determination of fatty acid species in oral mucosa where the relative increase of arachidonic and docosahexaenoic acids was observed in the early afternoon. This diurnal change of alkene peak position resembled the pattern of a “lipid factor” change calculated with the factor analysis applied to the overall infrared spectrum. We could monitor the diurnal fluctuations of PUFA contents of human oral mucosa noninvasively using a reagent‐free infrared analysis system. The measurement of alkene and methylene infrared bands may provide a useful tool for detecting changes in PUFA balance in the human body. © 2004 Wiley Periodicals, Inc. Biopolymers, 2004
Numerical simulation of the forest impact on aquifers
Authors: Leontiev A. , Huacasi W. , Herskovits J. , Mota Soares C. M. 
Published: April 2004

AbstractHere we propose a numerical method for the computer simulation of forest impact on aquifers. With this phenomenon we understand changes in the level of groundwater table beneath the areas recovered by trees. The mathematical model of the forest impact includes a boundary value problem with free and contact boundary conditions. Considering this free‐contact boundary problem as a shape optimization problem we perform boundary elements discretization. Assuming the state and free boundary variables as independents, we treat the discretized problem as a non‐linear mathematical program and apply interior point algorithm to solve it. Numerical results for an illustrative 2D test problem are discussed. Copyright © 2004 John Wiley & Sons, Ltd.
Analysis of coupled seepage and stress fields in rock mass around the Xiaowan arch dam
Authors: Junrui Chai , Yanqing Wu , Shouyi Li 
Published: April 2004

AbstractThe Xiaowan arch dam, with a maximum height of 292 m, is located across the Lancangjiang River in Yunnan Province of China, and once completed will be the highest arch dam in China. Because of the high water head and the arch action, it is necessary to analyse the interaction between seepage and stress fields in rock mass around the Xiaowan arch dam. Numerical solution of coupled seepage and stress fields in rock mass around the Xiaowan arch dam is analysed by means of the multi‐level fracture network model and the finite element method. It can be shown from the computation results that storage of the reservoir makes the seepage field change much, and makes the effective vertical stress in rock foundation near the dam and the tensile stress in the abutment rock mass increase, and that the coupled action between seepage and stress fields should be taken into account. Copyright © 2004 John Wiley & Sons, Ltd.
Egfl7, a novel epidermal growth factor‐domain gene expressed in endothelial cells
Authors: Fitch Michael J. , Campagnolo Luisa , Kuhnert Frank , Stuhlmann Heidi 
Published: April 2004

AbstractWe report the cloning and characterization of a novel epidermal growth factor (EGF) domain gene that was identified in a retroviral gene entrapment screen and is expressed in endothelial cells. This gene encodes a protein of 278 amino acids with an amino‐terminal signal peptide and two centrally located EGF‐like domains. We have named this novel gene in accordance with the guidelines of the Mouse Genome Informatics group Egfl7, for EGF‐like domain 7. Egfl7 mRNA is expressed in highly vascularized adult tissues such as the lung, heart, uterus, and ovary. In addition, Egfl7 is expressed early during mouse embryogenesis and in undifferentiated murine embryonic stem cells. The analysis of Egfl7 expression in embryonic day 9.5 embryos by in situ hybridization indicates that Egfl7 is expressed in vascular structures in both the embryo proper and the yolk sac and at sites of mesodermal precursors of angioblasts. Within the cell, EGFL7 protein is localized to the endoplasmic reticulum and Golgi apparatus, suggesting that the protein is targeted for secretion. Indeed, recombinant EGFL7 is readily detectable in the supernatant media of transiently transfected HEK293 cells. We also report the identification of an Egfl7 paralog, Egfl8, and show that EGFL8 protein shares similar domains and molecular weight with EGFL7. Developmental Dynamics 230:316–324, 2004. © 2004 Wiley‐Liss, Inc.
Environmental issues related to end‐of‐life options of plastics containing brominated flame retardants
Authors: Tange Lein , Drohmann Dieter 
Published: April 2004

AbstractBromine is used as the building block for some of the most effective flame retarding agents available to the plastics industry today. They are used to protect against the risk of accidental fires in a wide range of Electrical and Electronic Equipment (EEE). Brominated flame retardants (BFRs), as all flame retardants, act to decrease the risk of fire by increasing the fire resistance of the materials in which they are applied. There is a perception that BFRs affect adversely the end‐of‐life management of plastics through formation of Polybrominated Dibenzo Dioxins and Dibenzo Furans (PBDD/F). In fact, there exists a wide range of data and practical experience demonstrating that the end‐of‐life management of plastics containing BFRs is fully compliant with legislation setting the strictest limit values for PBDD/F and is fully compatible with an integrated waste management concept. Copyright © 2004 John Wiley & Sons, Ltd.
Numerical determination of 3D temperature fields in steel joints
Authors: Franssen Jean‐Marc 
Published: April 2004

AbstractA numerical study was undertaken to investigate the temperature field in steel joints and to compare the temperatures in the joints with the temperatures of the adjacent steel members on the hypothesis that the thermal protection is the same on the joint and in the members.Very brief information is given on the numerical model, supplemented with parametric studies made in order to determine the required level of discretization in the time and in the space domain. A simplified assumption for representing the thermal insulation is also discussed and validated.Different numerical analyses are performed, with a variation of the following parameters: (i) type of joints, from very simple to more complex configurations, with welds and/or bolts, all of them representing joints between elements located in the same plane; (ii) unprotected joints or protected by one sprayed material; (iii) ISO, hydrocarbon or one natural fire scenario.The fact that the thermal attack from the fire might be less severe because the joints are usually located in the corner of the compartment is not taken into account. Copyright © 2004 John Wiley & Sons, Ltd.
Advanced analysis of 3D steel framework exposed to compartment fire
Authors: Liew J. Y. Richard , Ma K. Y. 
Published: April 2004

AbstractThis paper describes the use of advanced analysis that accounts for both material and geometric nonlinearity to assess the performance of steel structures exposed to a natural compartment fire. The advanced analysis is developed based on inelastic beam‐column theory which can capture the ultimate strength behaviour of members for global analysis of large structures in fire. The heat transfer is computed using a refined finite element mesh. Compartment fire is simulated in accordance with the latest Eurocode prEN 1991‐1‐2. Performance‐based assessments are carried out on multi‐storey space frames subjected to a natural compartment fire. The computed results are compared with those from the conventional approach based on ISO standard fire curve and the advantage of the advanced analysis is highlighted. The effect of fire load and ventilation on the structural response of the frames is studied and the worst‐case fire scenarios are identified. The design implications on the requirement of fire protection are discussed. Copyright © 2004 John Wiley & Sons, Ltd.
Analytical method for the behaviour of a reinforced concrete flexural member at elevated temperatures
Authors: Kang Suk‐Won , Hong Sung‐Gul 
Published: April 2004

AbstractAn analytical method is proposed for the thermal behaviour of a reinforced concrete flexural member subjected to fire. The analysis procedure can be subdivided into two different steps; sectional analysis and member solution. A segmentation scheme is employed in the analysis for a section. It implicates uniform sectional properties and temperature distribution through the longitudinal axis of the member. The mechanical changes at the segmented section such as strain changes and corresponding stresses due to temperature increase are integrated into the member behaviour at the member solution step. According to the analysis results, there exist very severe nonlinear strain changes with the depth measured from the fire‐exposed surface, which are caused by a nonlinear temperature distribution at the section. Self‐equilibrating stresses are manifested during heating just to let the section remain plane after deformation. Copyright © 2004 John Wiley & Sons, Ltd.
Restraint of fire‐exposed concrete floor systems
Authors: Lim Linus , Buchanan Andrew H. , Moss Peter J. 
Published: April 2004

AbstractThis paper describes the numerical analyses of restrained concrete floor slabs exposed to fire. The analyses of the slabs were carried out with the SAFIR finite element program considering a 200 mm thick slab, spanning 5 m between two end supports. The slabs were exposed to the ISO standard fire for up to 4 h and were analysed with pinned and rotationally restrained supports. Different heights of the line of thrust at the supports and different levels of axial restraint were also investigated. The analyses show that fully restrained pin‐supported slabs can survive the 4 h ISO fire without collapse if the position of the line of thrust is located near the soffit of the slab. If the position of the line of thrust is located much above the soffit of the slab, the slabs will rapidly undergo large deformations and sag into a catenary, imposing axial tensile forces at the supports. The analyses have shown that even if the line of thrust is located close to the soffit, the slab can still deform into a catenary if there is insufficient horizontal axial restraint. In this study, rotationally restrained slabs experience much smaller vertical deflections than pin‐supported slabs when exposed to fires. Rotationally restrained slabs with low levels of horizontal restraint do not collapse, due to the beneficial effects of moment redistribution. However, high levels of horizontal restraint can be detrimental, causing slabs to collapse at advanced stages of the fire. Copyright © 2004 John Wiley & Sons, Ltd.