bluuebunny/crossref_metadata_2025 huggingface dataset:
Radiation and postirradiation crosslinking and structure of two unsaturated polyester resins
Authors: Pucić Irina , Jurkin Tanja
Published: July 2008

Radiation and postirradiation crosslinking of two unsaturated polyester (UP) resins were monitored, and substantial differences in the reaction course and extents were observed. DSC thermograms of one of the resins showed double peaks and significantly lower residual reaction heats. Extraction revealed that gelation dose of the resin with double peak was twice the gelation dose of the other resin that had single peak in DSC thermograms. Although other components of the polyesters were identical, NMR spectra of the resin with a single peak revealed isophthalic units while in the polyester of the resin having double DSC peaks orthophthalic units were detected. Orthophthalate reduced the compatibility of polyester and styrene and caused the reaction‐induced phase separation, influencing gel structure that was visible in scanning electron microscope micrographs. Previously, the double peaks in crosslinking thermograms of UP resins were usually attributed to initiator effects, but here no initiator was used, and, in the literature, we found that the double peaks are almost exclusively present in the thermograms of UP resins containing orthophthalates, whereas in resins with isophthalates double peaks almost never appear. Crosslinking extents were significantly higher in the resin‐containing isophthalate and in both cases enhanced by postirradiation reaction that is often neglected. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
Formation and characterization of polyurethane—vermiculite clay nanocomposite foams
Authors: Patro T. Umasankar , Harikrishnan G. , Misra Ashok , Khakhar Devang V.
Published: July 2008

Nanocomposites of rigid polyurethane foam with unmodified vermiculite clay are synthesized. The clay is dispersed either in polyol or isocyanate before blending. The viscosity of the polyol is found to increase slightly on the addition of clay up to 5 pphp (parts per hundred parts of polyol by weight). The gel time and rise time are significantly reduced by the addition of clay, indicating that the clay acts as a heterogeneous catalyst for the foaming and polymerization reactions. X‐ray diffraction and transmission electron microscopy of the polyurethane composite foams indicate that the clay is partially exfoliated in the polymer matrix. The clay is found to induce gas bubble nucleation resulting in smaller cells with a narrower size distribution in the cured foam. The closed cell content of the clay nanocomposite foams increases slightly with clay concentration. The mechanical properties are found to be the best at 2.3 wt% of clay when the clay is dispersed in the isocyanate; the compressive strength and modulus normalized to a density of 40 kg/m3 are 40% and 34% higher than the foam without clay, respectively. The thermal conductivity is found to be 10% lower than the foam without clay. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
Three‐dimensional simulation of primary and secondary penetration in a clip‐shaped square tube during a gas‐assisted injection molding process
Authors: Chau Shiu‐Wu
Published: July 2008

This article proposes a generalized Newtonian model to predict the three‐dimensional gas penetration phenomenon in the GAIM process, where the gas and melt compressibility are both taken into account and hence the primary and secondary penetrations in GAIM processes are able to be quantitatively predicted. Additionally, an incompressible model requiring no outflow boundary is also presented to emphasis the influence of gas compressibility on the primary penetration. Based on a finite volume discretization, the proposed numerical model solves the complete momentum equation with two front transport equations, which are employed to track the gas/melt and air/melt interfaces. The modified Cross‐WLF model is adopted to describe the melt rheological behavior. The two‐domain modified Tait equation is exploited to represent the melt compressibility, while a polytropic model is employed to express the gas compressibility. The proposed schemes are quantitatively validated by the gas penetration characteristics in a clip‐shaped square tube, where good prediction accuracy is obtained. The influences of five major molding parameters, such as the injection pressure, mold temperature, melt temperature, delay time, and melt material on the gas penetration characteristics in the same clip‐shaped square tube via the proposed numerical approach are extensively presented and discussed. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
Pressure and temperature behavior of thermoplastic polymer melts during high‐pressure expansion injection molding
Authors: Rogelj Sašo , Krajnc Matjaž
Published: July 2008

The development of expansion injection molding as new technology for producing thin plastic parts has raised questions about polymer melt behavior in the process of rapid high pressure compression and expansion. To investigate those phenomena, the new in‐line injection molding machine mounted measurement system has been developed. Measuring nozzle equipped with hydraulically driven closing bolts and contact fast response pressure and infrared temperature sensors enabled us to measure the compression and expansion of polymer melts at different starting conditions. Results presented for high impact polystyrene and polyamide show that polymer melt temperature rise is linearly dependent on compression pressure as well as it is dependent on compression speed. Comparable effect of temperature fall has been recorded during the polymer expansion, resulting in no noticeable loss of dissipation energy during this reversible process. Measurements have been compared with modified 2‐domain Tait equation of state. Curve fitting analysis to manufacturer's material data show that measurements fit well with the model, even at very high compression speeds. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
Mechanical and tribological properties of polyoxymethylene modified with nanoparticles and solid lubricants
Authors: Sun Lan‐Hui , Yang Zhen‐Guo , Li Xiao‐Hui
Published: July 2008

Polyoxymethylene (POM) composites modified with nanoparticles, polytetrafluoroethylene (PTFE) and MoS2 were prepared by a twin‐screw extruder. The effect of nanoparticles and solid lubricant PTFE/MoS2 on mechanical and tribological properties of the composites were studied. Tribological tests were conducted on an Amsler friction and wear tester using a block‐on‐ring arrangement under dry sliding and oil lubricated conditions, respectively. The results showed that generally speaking POM nanocomposites had better stiffness and tribological properties than corresponding POM composites attributed to the high surface energy of nanoparticles, except that the tensile strength of three composites and dry‐sliding tribological properties of POM/3%Al2O3 nanocomposite decreased due to the agglomeration of nanoparticles. Tribological properties differed under dry sliding and oil lubricated conditions. The friction coefficient and wear volume of POM nanocomposites under oil lubricated condition decreased significantly. The increased deformation resistance supported the increased wear resistance of POM nanocomposites. POM/PTFE/MoS2/3%Al2O3 nanocomposite had the best mechanical and tribological properties of all three composites, which was attributed to the synergistic effect of nanoparticles and PTFE/MoS2. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
Water bamboo husk reinforced poly(lactic acid) green composites
Authors: Wang Kuo‐Hsiung , Wu Tzong‐Ming , Shih Yeng‐Fong , Huang Chien‐Ming
Published: July 2008

The water bamboo husk is one of major agricultural wastes in Taiwan. In this study, the powder obtained from the water bamboo husk was added to poly(lactic acid) (PLA) to form novel reinforced biodegradable composites. Morphologies, mechanical properties, and heat resistance of these water bamboo powder reinforced composites were investigated. The results indicate that the char yields were increased as plant powder was incorporated to PLA. In addition, the mechanical properties were also enhanced due to the addition of powders. The increments of storage moduli of PLA were about 50–200%. Moreover, the increments of loss moduli of PLA were about 70–200%. On the other hand, the Tg of PLA was slightly decreased by the addition of powder, and this may improve the brittle characteristics of PLA. Furthermore, this type of reinforced PLA would be more environmental friendly than the artificial additive‐reinforced one. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
Prediction of residual stress and viscoelastic deformation of film insert molded parts
Authors: Kim Seong Yun , Oh Hwa Jin , Kim Sung Ho , Kim Chae Hwan , Lee Seung Hwan , Youn Jae Ryoun
Published: July 2008

Film insert molding (FIM) has been modeled numerically to predict residual stress and viscoelastic deformation of the part. Nonisothermal three dimensional flow analysis for filling, packing, and cooling stages was carried out by using a commercial software. It was assumed that the inserted film was solid throughout the entire molding procedure although remelting could occur at the interface with the substrate. The flow analysis results, e.g., temperature, stress, and density distribution in the substrate domain, were transported to a finite element stress analysis program for viscoelastic stress analysis. Deflection of the FIM part was obtained as soon as the part was ejected from the mold by assuming isotropic elastic material. The residual stress distribution in the FIM part was acquired by removing the constraints along the boundary of the molded part. Viscoelastic deformation of the FIM part was predicted by performing viscoelastic stress analysis in order to understand long term behavior of the FIM part when exposed to room temperature. Durability of automotive and electronic parts produced by the film injection molding can be predicted by the procedure adopted in this study. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
The morphology, mechanical properties, and flammability of aligned electrospun polycarbonate (PC) nanofibers
Authors: Moon SungCheal , Farris Richard J.
Published: July 2008

The electrospinning of the polycarbonate (PC) solutions was performed for the variable electrospinning parameters such as polymer concentration, solvent composition, applied voltage, flow rate, and take‐up velocity in order to evaluate changes of morphology, mechanical properties, and flammability of the aligned PC nanofibers as a function of the electrospinning parameters. It was found that the ratio of THF/DMF solvent in the electrospinning parameters had a major effect on the spinnability and fiber morphology. Furthermore, it was confirmed that the mechanical properties were dependent upon the fiber morphology. The spinnability of the PC solutions with a lower THF ratio in THF/DMF solvent was poor. The aligned electrospun PC fiber with the best morphology was made in the range of polymer concentration of 22%, solvent ratio of 50:50 THF : DMF, applied voltage of 14 kV, flow rate of 0.050 ml/m, and a take‐up velocity of 7.3 m/s. The ultimate strength and initial modulus of the 80% drawn 22% PC fiber were 64 ± 2 MPa (commercial 55–75 MPa) and 1.9 ± 0.1 GPa. The heat release capacity (HRC) of the 22 and 25% PC fiber were 275 ± 27 J/g K and 198 ± 1 J/g K. It was found that the flame resistance of the electrospun PC nanofiber was superior to that of the PC raw material (HRC ∼360 J/g K). POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
Uniaxial tensile properties underlying plane‐stress rapid fracture resistance in polyethylene
Authors: Özbek Pemra , Leevers Patrick
Published: July 2008

Developers of polyethylene grades for pressure pipe seek a deeper understanding of the resistance of these materials to high rate, plane‐stress fracture. The Reversed Charpy and ASTM F 2231 “Thin Charpy” test methods are designed to index this property, at appropriately high rates, for quality control and material development purposes. This article demonstrates the possibility of deriving equivalent information from a procedure based on tensile drawing tests, via two more basic material properties—yield stress and strain hardening modulus—which are more accessible to polymer design. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
Rheological characterization of starch derivatives/polycaprolactone blends processed by reactive extrusion
Authors: Bossard Frédéric , Pillin Isabelle , Aubry Thierry , Grohens Yves
Published: July 2008

Linear viscoelastic, steady shear behaviors, and morphologies of starch formate/poly(ε‐caprolactone) (PCL) blends, compatibilized by oligomers and obtained by reactive extrusion, have been investigated as a function of formic acid (FA)/starch ratio, nature, and molecular weight of the oligomer. The rheological properties of these blends have been compared with those of a commercial starch‐based thermoplastic, namely Mater‐Bi® ZF03UA. In presence of FA, starch is destructured to starch formate and oligomers are used as plasticizers. The linear viscoelastic response of blends is quite similar to that of nanocomposite materials: the low frequency behavior is attributed to a percolated network of destructured starch particles, and the high frequency behavior is that of the polymer matrix. The viscosity curve presents a profile characterized by two plateau regions, at low and high shear rates. The plateau region at low shear rates corresponds to the viscous response of the blend while that observed at high shear rates can be attributed to the PCL matrix. The compatibilization is enhanced in the presence of starch formate and increases with increasing the oligomer molecular weight. The use of PCL oligomer was shown to improve this compatibilization effect. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
Characterization of viscoelastic fluid flow in a periodically driven cavity: Flow structure, frequency response, and phase lag
Authors: Sriram S. , Deshpande Abhijit P. , Pushpavanam S.
Published: July 2008

Transport phenomena in periodically driven cavities are important because of their relevance in polymer processing and microfluidics. The transient periodic flow of viscoelastic fluids in a cuboidal cavity, with periodic motion of top plate, was studied in this work. Flow with a characteristic time scale was achieved through the simple harmonic motion of the top plate. The flow in the cavity was characterized by measuring planar velocity fields using particle image velocimetry (PIV). Temporal variation of velocity except at central vertical plane showed predominance of the plate frequency. The temporal point variations, though seemingly similar to those for Newtonian and purely viscous non‐Newtonian fluids, led to rich varieties of spatial flow structures in case of the viscoelastic fluids. The overall flow behavior was characterized using spatial variations, phase trajectories, and streamline patterns. The transition from low Reynolds number steady‐lid driven type flow to complex vortical patterned flow was observed during a cycle of periodic motion of viscoelastic fluids. The effects of elasticity and inertia on the flow fields were analyzed. Computational fluid dynamics simulations with purely viscous shear thinning fluid (power law) and Newtonian fluid showed significant differences with experimental measurements on viscoelastic fluids. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
Frequency of the sit‐to‐stand task: a pilot study of free‐living adults
Authors: Kerr Andy , Dall Philippa , Ryan Cormac
Published: July 2008

Purpose. To report contemporary data on the daily frequency of the sit‐to‐stand (STS) movement in a healthy, independently living, adult population. Relevance. As a key determinant of functional independence, which has a high mechanical load, the STS movement is a common feature of rehabilitation. Knowledge of STS frequency during daily activities could inform rehabilitation goals and content, but has rarely been examined. To date, only McLeod et al. (1975) have investigated this, reporting an average of 92 daily STS transitions in healthy young participants. Methods. Fifteen healthy, free‐living, ambulant adults (three males; mean age 40 years) were recruited from the general population. An activity monitor (activPALTM, PALtechnologies, Glasgow, UK) reported free‐living activity for each subject for seven consecutive days. Analysis. The average number of STS transitions per day was calculated from the whole period. Data were separated into working and non‐working days, and compared using a paired t‐test. Results. On average, participants performed 64 (±19) STS movements each day, with large individual differences [range 35–105]. Participants performed significantly (p = 0.047) more STS movements on a working day [68 (±24)] than on a non‐working day [55 (±17)]. Discussion. Fewer STS movements were recorded than previously reported (McLeod et al., 1975). This may reflect general changes in lifestyle; however, comparisons should consider the small samples involved and methodological differences. Conclusion. This study provides contemporary data for STS frequency and demonstrates a significant difference between working and non‐working days. This information could guide rehabilitation and future research. Copyright © 2008 John Wiley & Sons, Ltd.
Curcumin has anticonvulsant activity on increasing current electroshock seizures in mice
Authors: Bharal Nidhi , Sahaya Kinshuk , Jain Seema , Mediratta Pramod K. , Sharma Krishna K.
Published: July 2008

Epilepsy is one of the most common serious disorders of the brain. Several experimental studies have reported neuroprotective and antioxidant activity of certain natural products like curcumin, an active ingredient of turmeric. The present study was designed to explore the effect of acute administration of curcumin at doses 50, 100 and 200 mg/kg, orally (p.o.) and its chronic (× 21 days) administration in 100 mg/kg, p.o. on increasing current electroshock (ICES) test, elevated plus maze and actophotometer in mice. Curcumin in a dose of 100 mg/kg significantly increased the seizure threshold in ICES test on both acute and chronic administration. The same dose of 100 mg/kg on acute administration showed anxiogenic effect on elevated plus maze and actophotometer test. However, this anxiogenic effect of curcumin disappeared on chronic administration. These results suggest that curcumin appears to possess anticonvulsant activity in mice. Copyright © 2008 John Wiley & Sons, Ltd.
Imaging G‐SIMS: a novel bismuth‐manganese source emitter
Authors: Green Felicia M. , Kollmer Felix , Niehuis Ewald , Gilmore Ian S. , Seah Martin P.
Published: July 2008

G‐SIMS (gentle‐SIMS) is a powerful method that considerably simplifies complex static secondary ion mass spectrometry (SSIMS) analysis of organics at surfaces. G‐SIMS uses two primary ion beams that generate high and low fragmentation conditions at the surface. This allows an extrapolation to equivalent experimental conditions with very low fragmentation. Consequently, the spectra are less complex, contain more structural information and are simpler to interpret. In general, G‐SIMS spectra more closely resemble electron ionisation mass spectra than SSIMS spectra. A barrier for the wider uptake of G‐SIMS is the requirement for two ion beams producing suitably different fragmentation conditions and the need for their spatial registration (spatial alignment) at the surface, which is especially important for heterogeneous samples. The most popular source is the liquid metal ion source (LMIS), which is now sold with almost every new time‐of‐flight (TOF)‐SIMS instrument. Here, we have developed a novel bismuth‐manganese emitter (the ‘G‐tip’) for the popular LMISs. This simplifies the alignment and gives excellent G‐SIMS imaging and spectroscopy without significantly compromising the bismuth cluster ion beam performance. © Crown copyright 2008. Reproduced with the permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd.
A practical approach to robotic design for the DARPA Urban Challenge
Authors: Patz Benjamin J. , Papelis Yiannis , Pillat Remo , Stein Gary , Harper Don
Published: July 2008

This article presents a practical approach to engineering a robot to effectively navigate in an urban environment. Inherent in this approach is the use of relatively simple sensors, actuators, and processors to generate robot vision, intelligence, and planning. Sensor data are fused from multiple low‐cost, two‐dimensional laser scanners with an innovative rotational mount to provide three‐dimensional coverage with image processing using both range and intensity data. Information is combined with Doppler radar returns to yield a world view processed by a context‐based reasoning control system to yield tactical mission commands forwarded to traditional proportional‐integral‐derivative (PID) control loops. As an example of simplicity and robustness, steering control successfully utilized a relatively simple follow‐the‐carrot guidance approach that has been successfully demonstrated at speeds of 60 mph (97 km/h). The approach yielded a robot that reached the finals of the Urban Challenge and completed approximately 2 h of the event before being forced to withdraw as a result of a global positioning system data failure. © 2008 Wiley Periodicals, Inc.
Team Cornell's Skynet: Robust perception and planning in an urban environment
Authors: Miller Isaac , Campbell Mark , Huttenlocher Dan , Kline Frank‐Robert , Nathan Aaron , Lupashin Sergei , Catlin Jason , Schimpf Brian , Moran Pete , Zych Noah , Garcia Ephrahim , Kurdziel Mike , Fujishima Hikaru
Published: July 2008

Team Cornell's Skynet is an autonomous Chevrolet Tahoe built to compete in the 2007 DARPA Urban Challenge. Skynet consists of many unique subsystems, including actuation and power distribution designed in‐house, a tightly coupled attitude and position estimator, a novel obstacle detection and tracking system, a system for augmenting position estimates with vision‐based detection algorithms, a path planner based on physical vehicle constraints and a nonlinear optimization routine, and a state‐based reasoning agent for obeying traffic laws. This paper describes these subsystems in detail before discussing the system's overall performance in the National Qualifying Event and the Urban Challenge. Logged data recorded at the National Qualifying Event and the Urban Challenge are presented and used to analyze the system's performance. © 2008 Wiley Periodicals, Inc.
Autonomous driving in urban environments: Boss and the Urban Challenge
Authors: Urmson Chris , Anhalt Joshua , Bagnell Drew , Baker Christopher , Bittner Robert , Clark M. N. , Dolan John , Duggins Dave , Galatali Tugrul , Geyer Chris , Gittleman Michele , Harbaugh Sam , Hebert Martial , Howard Thomas M. , Kolski Sascha , Kelly Alonzo , Likhachev Maxim , McNaughton Matt , Miller Nick , Peterson Kevin , Pilnick Brian , Rajkumar Raj , Rybski Paul , Salesky Bryan , Seo Young‐Woo , Singh Sanjiv , Snider Jarrod , Stentz Anthony , Whittaker William “Red” , Wolkowicki Ziv , Ziglar Jason , Bae Hong , Brown Thomas , Demitrish Daniel , Litkouhi Bakhtiar , Nickolaou Jim , Sadekar Varsha , Zhang Wende , Struble Joshua , Taylor Michael , Darms Michael , Ferguson Dave
Published: July 2008

Boss is an autonomous vehicle that uses on‐board sensors (global positioning system, lasers, radars, and cameras) to track other vehicles, detect static obstacles, and localize itself relative to a road model. A three‐layer planning system combines mission, behavioral, and motion planning to drive in urban environments. The mission planning layer considers which street to take to achieve a mission goal. The behavioral layer determines when to change lanes and precedence at intersections and performs error recovery maneuvers. The motion planning layer selects actions to avoid obstacles while making progress toward local goals. The system was developed from the ground up to address the requirements of the DARPA Urban Challenge using a spiral system development process with a heavy emphasis on regular, regressive system testing. During the National Qualification Event and the 85‐km Urban Challenge Final Event, Boss demonstrated some of its capabilities, qualifying first and winning the challenge. © 2008 Wiley Periodicals, Inc.
Magnetization‐induced optical second harmonic generation from the surface of Co‐doped rutile TiO2(110)
Authors: Watanabe R. , Yuasa M. , Yahata Y. , Mizutani G. , Suzuki T. , Segawa Y. , Matsumoto Y. , Yamamoto Y. , Koinuma H.
Published: July 2008

We have investigated the surface magnetism of 5 at% Co‐doped rutile TiO2(110) using magnetization‐induced optical second harmonic generation (MSHG) in the longitudinal Kerr configuration with the incident beam angle of 4° . MSHG is observed at both 2ħω = 2.33 eV and 2ħω = 4.20 eV. MSH intensity showed a hysteresis as a function of the external magnetic field for the second harmonic photon energy of 2ħω = 4.20 eV at which the absorption length limits the MSHG origin to the surface layer of 10 nm due to the TiO2 bulk. Since 5 at% Co: TiO2(110) is judged to have no metallic Co near the top surface by XPS, the hysteresis is attributed to a carrier‐induced ferromagnetism at the surface of this material. Copyright © 2008 John Wiley & Sons, Ltd.
First‐principles study of the (001) surface of cubic PbTiO3
Authors: Zhang Jian‐Min , Pang Qing , Xu Ke‐Wei , Ji Vincent
Published: July 2008

We present first‐principles calculations on the (001) surfaces of cubic PbTiO3 with PbO and TiO2 terminations. The cleavage energy, surface energy, surface grand potential, surface relaxation and surface electronic structure have been investigated by using the projector‐augmented wave method under generalized gradient approximation (GGA). The results show that surface energy of a TiO2‐terminated surface is a little lower than that of a PbO‐terminated one, thus allowing both terminations to coexist. The PbO‐termination is stable in O‐ and Pb‐rich environments, while on the contrary, the TiO2‐termination is stable in O‐ and Pb‐poor conditions. In addition, the surface rumpling S of a PbO‐terminated surface is slightly larger than that of a TiO2‐terminated one. The relaxations dominantly take place on the outermost three layers, and an oscillatory (− + −) damping (|Δd12 | > | Δd23 | > | Δd34|) relaxation phenomenon appears for both terminations. The band gaps of both PbO‐ and TiO2‐terminations are slightly lower than that of the bulk. Moreover, the DOS curves of each layer show that for the TiO2‐termination, the top of the valence band of the first and third TiO2 layers moves toward Fermi level. Copyright © 2008 John Wiley & Sons, Ltd.
A survey of nurses who experienced trauma in the workplace: influence of coping strategies on traumatic stress
Authors: Niiyama Etsuko , Okamura Hitoshi , Kohama Akitsugu , Taniguchi Takahide , Sounohara Mitsuhiko , Nagao Mitsushiro
Published: July 2008

Decreasing traumatic stress is a key issue for nurses who experience trauma, but trauma of nurses in the workplace has only rarely been investigated in detail. This study was designed to characterize trauma of nurses in the workplace in detail, and to make comparison of coping strategies employed by nurses who recovered from traumatic stress and those of nurses with persistent traumatic stress. A study of trauma was conducted by asking 782 nurses to complete a questionnaire. Valid responses were provided from 592 nurses. Free descriptions of trauma were analysed using the KJ method to characterize the trauma of nurses. A comparison of scores on coping subscales in the persistent trauma group and recovery group was made by the unpaired t‐test. Of the 592 nurses, 301 female nurses had experienced trauma in the workplace. The analysis revealed that 50 nurses (17 per cent) recovered from traumatic stress, while 251 (83 per cent) had persistent traumatic stress. Trauma predominantly consisted of direct exposure to violent language or non‐supportive behaviour by physicians, followed by witnessing and learning of experiences. The results suggested that ‘positive action’, ‘positive thinking’, ‘cognitive avoidance’, ‘uncontrolled thinking’ and ‘talking’ lead to persistence of traumatic stress. Copyright © 2008 John Wiley & Sons, Ltd.
Experiences and results from tailoring and deploying a large process standard in a company
Authors: Armbrust Ove , Ebell Jan , Hammerschall Ulrike , Münch Jürgen , Thoma Daniela
Published: July 2008

With increasing process maturity of the software developing companies, an increasing interest in standardized processes can be observed. Company‐specific standards are often derived from reference standards such as ISO/IEC 12207 or the German V‐Modell XT. Developing and deploying a (new) company‐wide standard is a challenging task with many obstacles. Many efforts in defining and deploying standard processes in a company do not result in sufficient adherence between the defined and the lived (i.e. the enacted) process. Such situations have severe consequences, e.g. it is not possible to measure processes. Published experience with process definition and deployment projects is often anecdotal or incomplete. This paper describes the adaptation of a generic process standard to an organization and its deployment to daily practice. In this article, the approach taken for adapting and deploying the V‐Modell XT in the data processing department of the German Josef Witt GmbH is described. Additionally, effort data and lessons learned with respect to these activities are given. Finally, effects visible so far are sketched. Copyright © 2008 John Wiley & Sons, Ltd.
Using seismic isolation columns for retrofitting buildings with soft stories
Authors: Briman V. , Ribakov Y.
Published: July 2008

Base isolation is known as en effective way to improve structural seismic response and reduce damages that may be caused to structures by earthquakes. The objective of seismic isolation is to decouple the structure from the earthquake motion input, preventing the structure from absorbing the earthquake energy. A new engineering solution for seismic isolation columns is presented in this study. It is aimed first of all at retrofitting existing buildings with a soft storey by replacing weak conventional columns, having low static and dynamic load carrying capacity, by the proposed ones. The idea is based on a well known friction pendulum principle. The proposed seismic isolation column is a kinematic system. Its main joint has high load carrying capacity as well as all properties of a three‐dimensial hinge connection. No special materials are required for its manufacturing. No special lifting equipment is required to replace the conventional columns in existing structures by the proposed ones. An additional advantage is that manufacturing of such seismic isolation columns is relatively easy and does not require high accuracy and testing of each unit, like in other types of base isolators. A method for design of buildings, incorporating the proposed devices, was developed. The developed design procedure was applied for a multi‐storey RC frame with infill walls in a numerical example. It was shown that using the proposed solution yields significant improvement in structural response to earthquakes. Copyright © 2008 John Wiley & Sons, Ltd.
The melting temperature (or not melting) of poly(vinyl chloride)
Authors: Summers James W.
Published: July 2008

The best answer to what is the melting temperature of PVC is its previous processing temperature. That temperature is where secondary crystallites, created by gelation, melt and allow the primary particle flow units to flow again independently. In the case of powder compounds being processed for the first time, the question of melting is less relevant. The PVC, out of the polymerizer, contains crystallites that are not completely meltable. The issue is how easily the grains of PVC disperse to primary particle flow units. This property depends on polymerization conditions and the type of processing equipment. The temperature achieved affects the amount of fusion (gelation). J. VINYL ADDIT. TECHNOL., 2008. © 2008 Society of Plastics Engineers.
Nanoscopic characterization of a plastisol gelation and fusion process utilizing scanning electron microscopy and atomic force microscopy
Authors: Jourdan Jerome S. , Owen David P.
Published: July 2008

Understanding the physical properties associated with the gelation and fusion of a PVC plastisol will help to improve process efficiency. Plastisol gelation and fusion were characterized by using both scanning electron microscopy (SEM) and atomic force microscopy (AFM) and were compared with the tensile properties developed at various temperatures. Both SEM and AFM showed good agreement during the early stages of gelation. However, AFM continued to show particle boundaries during the latter stages of gelation and fusion that provided a more nearly accurate comparison with the resulting tensile properties. J. VINYL ADDIT. TECHNOL., 2008. © 2008 Society of Plastics Engineers.
Landfill degradation of vinyl compositions
Authors: Grossman Richard F.
Published: July 2008

The ideal degradable vinyl compound would disappear into the landfill, forming biomass without toxic contaminants, while evolving gas that could be used for fuel, without the additives used causing loss of processing or service life. The types of additives that might be useful in promoting such behavior are discussed. J. VINYL ADDIT. TECHNOL., 2008. © 2008 Society of Plastics Engineers.
Effect of magnesium malonate on the formation of the β crystalline form in isotactic polypropylene
Authors: Dou Qiang , Lu Qu‐Liang
Published: July 2008

Magnesium malonate (MgMt) is used to induce the β crystalline form in isotactic polypropylene (iPP) for the first time. It is shown by wide angle X‐ray diffraction, differential scanning calorimetry, and polarized light microscopy that the content of the β crystalline form increases markedly with the addition of MgMt and attains the maximum value at an MgMt content of 0.10wt%. The tensile strength and flexural modulus of the doped iPP sample decrease somewhat; the tensile strain at break increases slightly; and the Izod notched impact strength increases significantly with the addition of MgMt, as compared with the values for the blank iPP sample. The β‐nucleation mechanism of MgMt is analyzed by the dimensional lattice match criterion. J. VINYL ADDIT. TECHNOL., 2008. © 2008 Society of Plastics Engineers.
Food and feeding preferences of Himalayan gray goral (Naemorhedus goral bedfordi) in Pakistan and Azad Jammu and Kashmir
Authors: Fakhar‐i‐Abbas F. , Akhtar Tanveer , Mian Afsar
Published: July 2008

Himalayan gray goral is endemic to Himalayas and Hindukush ranges. Analysis of 15 fecal samples and field observations from different areas of Pakistan and Azad Kashmir suggest that goral consumes foliage of a minimum of 28 plant species. Trees, shrubs and grasses appear in the ratio of 1:36:63 and hence the species is a grazer, though may opt for browsing when forced. The species mainly subsists on six species of grasses (Chrysopogon aucheri=17.97%, Themeda anathera=13.03%, Poa pratensis=11.23%, Digitaria decumbens=9.30%, Apluda mutica=7.51%, Aristida cyanatha=3.15%), though leaves of shrubs (Myrsine africana=11.38%, Daphne oleoides=8.87%, Carissa opaca=5.94%, Dodonaea viscose=4.79%, Rubus ellipticus=2.93%, Gymnosporia royleana=1.29%) are also consumed. Food preference indices (consumed/availability) suggest that grasses are highly preferred (16.86 times of availability), followed by shrubs (3.3 times of availability), whereas trees and herbs are not preferred. Food plants contain water (77.9±0.56%), ash (8.6±0.38%), sugars (6.8±0.16%), proteins (5.6%±0.28%) and fats (1.3±0.08%). Food provides 4,440 kcal of energy and 5.45 L of water/day/adult goral, which is sufficient to meet the requirements of the species. Grasses need to be ensured in the protected area separated for management of goral population. Zoo Biol 27:371–380, 2008. © 2008 Wiley‐Liss, Inc.
Potential impacts of flooding events and stream modification on an endangered endemic plant,Schoenoplectus gemmifer(Cyperaceae)
Authors: Kitamura Koshi , Yoshimura Jin , Tainaka Kei‐ichi , Yokojima Satoshi
Published: July 2008

River management often conflicts with the conservation of species in river ecosystems. In Japan, almost all river systems have been covered by concrete walls. Such river improvement works caused critical damage to river ecosystems. Here we report the ongoing extinction process of a rare aquatic plant by several consecutive heavy rains. The aquatic plant,Schoenoplectus gemmiferC. Sato, T. Maeda & Uchino, is an extremely rare endemic species that is strictly associated with springwater. The species is only found in 23 locations in Japan, including only two major habitats: Hamamatsu and Oita. We monitored the population fluctuations ofS. gemmiferat three river systems in Hamamatsu. In the largest habitat, Higashikanda River, the population size of the species decreased to nearly 1/10th in 2004, due to several severe floods. Spatial and temporal records exhibit four stages of damaging process. The stepwise damages were found to be caused by a rapid flow of water accelerated by the river improvement work (made in 1985). The reproduction and growth by seeds and gemmae did not evidently cover the losses by flood washed out. In the other two rivers, one was extinct and the other is now at the risk of extinction. The modified river structures may be responsible for the near‐extinction ofS. gemmiferin Hamamatsu area. We propose two policies for the conservation of this species: (1) the artificial cultivation of gemmae and seedlings and (2) the modification of river structure to decrease the number of washed‐out plants. In particular, it is important to decrease the water velocity at floods by some methods.
Antimicrobial Activity of Essential Oils Isolated from Phlomis crinita Cav. ssp. mauritanica Munby
Authors: Limem‐Ben Amor Ilef , Neffati Aicha , Ben Sgaier Mohamed , Bhouri Wissem , Boubaker Jihed , Skandrani Ines , Bouhlel Ines , Kilani Soumaya , Ben Ammar Rebai , Chraief Imed , Hammami Mohamed , Ghoul Mohamed , Chekir‐Ghedira Leila , Ghedira Kamel
Published: July 2008

The essential oil extracted from the leaves and flowers of Phlomis crinita Cav. ssp. mauritanica Munby were obtained by steam distillation and analyzed by gas chromatography coupled with mass spectrometry. The major constituents of flower oil were β‐caryophyllene (58.1%) and germacrene D (35.1%). This oil inhibited the growth of Staphylococcus aureus, Enterococcus faecalis, and Salmonella typhimurium with minimal inhibition concentrations (MIC) varying between 39 and 625 μg/ml. The essential oil obtained from the leaves was mainly composed of trans‐caryophyllene (40.8%) and germacrene D (39.1%) and exhibited an antimicrobial profile against the same strains mentioned above with MIC between 156 μg/ml and 2.5 mg/ml.
Metabolic and orthopedic management of X-linked vitamin D-resistant hypophosphatemic rickets
Authors: Fucentese Sandro F. , Neuhaus Thomas J. , Ramseier Leonhard E. , Ulrich Exner G.
Published: July 2008

Purpose

Therapy of vitamin D-resistant hypophosphatemic rickets (VDXLR) consists of oral phosphate and vitamin D supplements. Bone deformities, pain, and small stature can occur even in children with good compliance, requiring surgical correction and bone lengthening. However, only few surgical reports are available.

Methods

Twelve patients (three males) with VDXLR were followed at our institution. Median age at diagnosis was 3 9/12 years (range, birth to 11 10/12) with a follow-up period of 7 8/12 years (1 9/12–30) and age at last follow-up of 13 6/12 years (2–30). Eight patients underwent surgical correction, three of them in combination with bone lengthening. The corrections were performed at the end of growth in three patients. Clinical endpoints were height, leg axis, and pain.

Results

Single bilateral surgical correction was performed in six patients; one patient each had three and five corrections. Bone lengthening was performed in three patients. At last follow-up, the height of seven operated patients was within normal range. In addition, leg axis was normalized in six patients with mild genua vara in two. Only one patient complained of intermittent pain. Bone healing was excellent; surgical complications were rare. There was no radiological evidence of degenerative arthropathy.

Conclusions

Medical treatment remains the main pillar of therapy in children with VDXLR. In case of bone deformity, surgery can safely be performed, independent of age or bone maturation. All patients were satisfied with the results of axial corrective surgery and bone lengthening, and in the majority only one corrective intervention was needed.
Arthrographic indicators for decision making about femoral varus osteotomy in Legg-Calvé-Perthes disease
Authors: Kamegaya Makoto , Saisu Takashi , Takazawa Makoto , Nakamura Junichi
Published: July 2008

Purpose

There is not always a good outcome after a femoral varus osteotomy (FVO) in those with Legg-Calvé-Perthes disease (LCPD), even when the severity warrants surgical treatment. The purpose of this study was to find arthrographic indicators for decision making regarding the likely surgical outcome of a FVO.

Methods

We used an image of an abduction position during preoperative arthrography under general anesthesia that simulated the post-operative relationship between the femoral head and the acetabulum. In the image, we defined two indicators of how deeply the deformed epiphysis was contained within the acetabulum: an acetabular head index in abduction and an epiphyseal slip-in index. Finding the contact point between the top of epiphysis and acetabulum was the key for the epiphyseal slip-in index measurement. In 37 patients (38 hips) who underwent FVOs based on our inclusion criteria, these two indices were measured retrospectively and were analyzed for a correlation with surgical outcome. Surgical outcome was evaluated using a combination of three factors: sphericity of the femoral head (Stulberg's classification), acetabular cover (acetabular head index), and the slope of acetabular roof.

Results

The outcome was acceptable in 20 hips (52.6%) and unacceptable in18 hips (47.4%). There was a statistically significance difference in epiphyseal slip-in index between the acceptable group (21.9 ± 2.8%) and the unacceptable group (15.0 ± 4.4%) ( P < 0.0001). An index of 20% or more determined a safe zone for predicting an acceptable outcome with 80% sensitivity, 89% specificity, and a 7.2 likelihood ratio. However, the acetabular head index in abduction showed no such statistical significance.

Conclusions

In this study, we found that the epiphyseal slip-in index was a reliable indicator for predicting the effectiveness of a FVO. It is worth measuring this index when a surgeon is considering a FVO for a patient with severe LCPD. (Level of Evidence Level III.)
The nociceptive mechanism of 5‐hydroxytryptamine released into the peripheral tissue in acute inflammatory pain in rats
Authors: Nakajima Kunie , Obata Hideaki , Ito Naomi , Goto Fumio , Saito Shigeru
Published: July 2008

The present study examined the contribution of 5‐hydroxytryptamine (5‐HT) to acute peripheral inflammatory pain in rats. We used formalin test in this study. After formalin injection into the rat hind paw, biphasic pain‐related behavior (phases 1 and 2) was observed. A microdialysis study revealed that 5‐HT was released into the formalin injection site in a formalin concentration‐dependent manner (1.25–5%), and its peak time was 18min after the injection. Previous studies suggest that peripheral 5‐HT2 receptors are involved in inflammatory pain. Therefore, we next examined whether 5‐HT2A and 5‐HT2C receptors are involved, and from where 5‐HT is released in the formalin test. Local pretreatment with a selective 5‐HT2A receptor antagonist, ketanserin, and selective 5‐HT2C receptor antagonists, RS102221 and SB242084, inhibited the number of flinches in early part of phase 2 (phase 2A) of the formalin test in a dose‐dependent manner. Peripheral pretreatment with sodium cromoglycate (cromolyn), a mast cell membrane stabilizer, completely suppressed 5‐HT release and inhibited phase 2 responses of the formalin test. These drugs inhibited c‐fos expression in the superficial layer of the spinal dorsal horn of segments L4‐5 at 2h after formalin injection. These results indicate that 5‐HT released into peripheral tissue and its receptors, 5‐HT2A as well as 5‐HT2C, at the periphery have an important role in pain‐related behaviors during acute peripheral inflammation.
Microtubule‐associated Protein 1B Light Chain (MAP1B‐LC1) negatively regulates the activity of tumor suppressor p53 in neuroblastoma cells
Authors: Lee So-Youn , Kim Jung-Woong , Jeong Mi-Hee , An Joo-Hee , Jang Sang-Min , Song Ki-Hyun , Choi Kyung-Hee
Published: July 2008

MINT‐6701342, MINT‐6706444:

MAP1B‐LC (uniprotkb:P46821) and P53 (uniprotkb:P04637) colocalize (MI:0403) by fluorescence microscopy (MI:0416)

MINT‐6700861, MINT‐6701791:

P53 (uniprotkb:P04637) physically interacts (MI:0218) with MAP1B‐LC (uniprotkb:P46821) by anti bait coimmunoprecipitation (MI:0006)

MINT‐6702266, MINT‐6702529:

P53 (uniprotkb:P04637) physically interacts (MI:0218) with MAP1B‐LC (uniprotkb:P46821) by anti tag coimmunoprecipitation (MI:0007)
Double‐membrane gap junction internalization requires the clathrin‐mediated endocytic machinery
Authors: Gumpert Anna M. , Varco Joseph S. , Baker Susan M. , Piehl Michelle , Falk Matthias M.
Published: July 2008

Direct cell–cell communication mediated by plasma membrane‐spanning gap junction (GJ) channels is vital to all aspects of cellular life. Obviously, GJ intercellular communication (GJIC) requires precise regulation, and it is known that controlled biosynthesis and degradation, and channel opening and closing (gating) are exploited. We discovered that cells internalize GJs in response to various stimuli. Here, we report that GJ internalization is a clathrin‐mediated endocytic process that utilizes the vesicle‐coat protein clathrin, the adaptor proteins adaptor protein complex 2 and disabled 2, and the GTPase dynamin. To our knowledge, we are first to report that the endocytic clathrin machinery can internalize double‐membrane vesicles into cells.
Amyloidogenic properties of transthyretin‐like protein (TLP) fromEscherichia coli
Authors: Santos Sofia Duque , Costa Rita , Teixeira Pedro Filipe , Gottesman Max , Cardoso Isabel , Saraiva Maria João
Published: July 2008

We report the amyloid‐like properties ofEscherichia colitransthyretin‐like protein (TLP). TLP is 32% homologous to human transthyretin (hTTR), and is also tetrameric. In contrast to hTTR, TLP does not bind thyroxine. TLP orthologues are found in several prokaryotes, lower eukaryotes and vertebrates. TLP carries a signal peptide that targets the protein to the periplasmic space. We found that TLP and hTTR tetramers dissociate into monomers under similar conditions, although TLP monomers have different association properties. Like hTTR, TLP forms aggregates, small fibrillar structures of 8 nm width, and annular structures of 8 nm diameter which present amyloid‐like properties and are toxic to cells.
Betacellulin stimulates growth of the mouse intestinal epithelium and increases adenoma multiplicity in Apc+/Min mice
Authors: Dahlhoff Maik , Horst David , Gerhard Markus , Kolligs Frank T. , Wolf Eckhard , Schneider Marlon R.
Published: July 2008

We employed transgenic mice overexpressing betacellulin (BTC) to study its effects in the gut. BTC stimulated crypt cell proliferation and markedly increased intestinal size, while the crypt‐villus architecture was preserved. Introduction of a dominant negative epidermal growth factor receptor (EGFR) completely abolished the intestinal hyperplasia. BTC increased polyp multiplicity but did not change the mean size or the histological quality of intestinal polyps in Apc
+/Min
mice. Analysis of intact and cleaved caspase‐3 levels indicated that BTC has anti‐apoptotic effects in the intestinal epithelium. We conclude that increased BTC levels support the survival of nascent adenomas in Apc
+/Min
mice, resulting in a larger total polyp number at later stages.