bluuebunny/crossref_metadata_2025 huggingface dataset:
Improvement of the photostability of isotactic polypropylene by the incorporation of ethylene
Authors: Alam Md. Shamsul , Nakatani Hisayuki , Goss Ben G. S. , Ichiki Tomohito , Liu Boping , Terano Minoru
Published: October 2002

The effect of the incorporation of ethylene on the photostability of isotactic poly(propylene) (iPP) was studied with the aim of improving the photostability. iPP was prepared with a random ethylene sequence (ethylene–propylene random copolymer, rPP), and the photooxidative degradation behavior was compared with that of homogeneous iPP. Both samples were thermally post‐treated under vacuum to ensure the same crystallinity. The degradation behavior was studied by infrared spectroscopy (IR), gel permeation chromatography (GPC), and temperature rising elution fractionation (TREF) measurements. The rates of hydroperoxide and carbonyl formation in the irradiated iPP increased with irradiation time for > 192 h, whereas those in the irradiated rPP are almost constant after 96 h. The change in molecular weight with the irradiation time showed similar behavior, suggesting that the degradation reaction in the irradiated rPP was suppressed after 96 h. The degradation behavior of rPP was thought to be due to the dissociation of the methyl group, which leads to the termination of degradation. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 1863–1867, 2002
Molecular structure and physical properties of E‐beam crosslinked low‐density polyethylene for wire and cable insulation applications
Authors: Dadbin Susan , Frounchi Masoud , Saeid M. Haji , Gangi Fazel
Published: October 2002

Crosslinking of homemade low‐density polyethylene (LDPE) was performed by electron‐beam (EB) irradiation. The gel content of the EB‐exposed LDPE was determined by the solvent‐extraction method. The degree of crosslinking was also evaluated by a hot set measuring test. The results obtained from both the gel–sol and the hot set methods showed that the degree of crosslinking was dependent on the deposited energy in LDPE samples. Increasing the absorbed dose increased the degree of network formation. The LDPE with higher molecular weight yielded higher efficiency of crosslinking at the same irradiation dose. The effect of irradiation dose on the molecular weight between crosslinks (Mc), glass‐transition temperature, and free volume were calculated. Mechanical test results showed that the tensile strength of the samples increased with increase in the irradiation dose up to 150 kGy and then slightly decreased with further increasing the deposited energy. The elongation at break decreased with increasing the absorbed dose. The results obtained from differential scanning calorimetry exhibited a small reduction in the melting point and the degree of crystallinity of the EB‐exposed LDPE samples compared to those of the untreated samples. The effect of crosslinking on the electrical properties of the irradiated samples was insignificant. The dielectric constant of the treated samples remained nearly constant within the irradiation dose range, although the dissipation factor increased slightly with increasing the absorbed dose. The results obtained from characterizing the EB‐induced crosslinking of homemade polyethylene, including LH0030 and LH0075, showed the higher molecular weight polyethylene (LH0030) as a preferred option for wire and cable insulation. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 1959–1969, 2002
Viscoelastic properties of young and old human dermis: A proposed molecular mechanism for elastic energy storage in collagen and elastin
Authors: Silver Frederick H. , Seehra Gurinder P. , Freeman Joseph W. , DeVore Dale
Published: October 2002

We have studied the strain‐rate dependency of the viscoelastic mechanical properties of human dermis from young (23‐year‐old) and old (87‐year‐old) donors using incremental stress–strain measurements. The elastic spring constant for elastic fibers was found to be strain‐rate and age dependent, whereas that for collagen was only age dependent. Fibril lengths were observed to decrease with increased strain rates and age for both elastic and collagen fibers; however, the large decrease in collagen fibril viscosity was hypothesized to be a result of thixotropy that results when neighboring collagen fibrils slide by each other. It is concluded that the elastic spring constant measured for elastic fibers may be higher than previously reported and is consistent with stretching of α‐helical segments of elastin into a more extended conformation during the initial part of the elastic stress–strain curve. The decrease in the elastic spring constant with increased age observed is consistent with disruption of the elastic fibers and loss of α‐helical structure. The pH dependency of the elastic modulus reported previously for collagen suggests that charge–charge interactions within and between collagen molecules are involved in energy storage during stretching. Elastic energy storage is consistent with the stretching of charged pairs located in flexible regions of the collagen molecule. Shear thinning, or thixotropy of skin, is hypothesized to reflect breakage of bonds that occur between collagen fibrils. It is hypothesized that both collagen and elastin are complex macromolecules that are hybrids of flexible and rigid regions. The flexible regions reversibly store elastic energy during stretching by breakage of secondary bonds. After stretching, the flexible regions become extended and transfer stress to the rigid regions of these molecules. This prevents premature mechanical failure of collagen and elastic fibers in the dermis. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 1978–1985, 2002
Toughening liquid‐crystalline polymers with polyethylenes containing epoxy functionality
Authors: Tynys A. , Hippi U. , Seppälä J.
Published: October 2002

To improve toughness, a liquid‐crystalline polymer (LCPs) was blended with polyethylenes containing epoxy functionality in concentrations of 2, 6, and 15 wt %. The blends were prepared with a corotating twin‐screw extruder and were injection‐molded into specimens for mechanical testing. The effect of the amount of the epoxy‐functionalized polyethylenes on the morphology and mechanical and thermal properties was studied. The toughness improved with increasing amount of functionalized polyethylene, and the blend containing 15 wt % epoxy‐functionalized polyethylene had the best toughness properties. Impact strength values up to three times higher than those of the neat LCP were achieved. However, the stiffness of the LCP concurrently decreased substantially. The morphology became much more uniform, and the melting behavior changed. The results show that considerable improvements in the toughness properties of LCPs can be achieved with epoxy‐functionalized polyethylenes. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 1886–1891, 2002
Morphology and hydrolysis of PCL/PLLA blends compatibilized with P(LLA‐co‐ϵCL) or P(LLA‐b‐ϵCL)
Authors: Choi Nam‐Soon , Kim Chang‐Hyeon , Cho Kuk Young , Park Jung‐Ki
Published: October 2002

The effect of the compatibilizers, P(LLA‐co‐ϵCL) and P(LLA‐b‐ϵCL), on the morphology and hydrolysis of the blend of poly(ϵ‐caprolactone) (PCL) and poly(L‐lactide) (PLLA) was investigated. An addition of P(LLA‐co‐ϵCL) or P(LLA‐b‐ϵCL) into the blend could enhance the compatibility between the dispersed PCL domains and the PLLA matrix. The size of the PCL domains in the PLLA/PCL (70/30) blend containing P(LLA‐co‐ϵCL) reduced more significantly with an increase in the content of the compatibilizer than that in the blend containing P(LLA‐b‐ϵCL). The molecular weight of the PLLA/PCL blend films compatibilized with P(LLA‐co‐ϵCL) or P(LLA‐b‐ϵCL) decreased during the hydrolysis and the decrease of the molecular weight of the blend films compatibilized with P(LLA‐co‐ϵCL) was much more significant than that of the blend films compatibilized with P(LLA‐b‐ϵCL). © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 1892–1898, 2002
Dynamic modeling of curing process of epoxy prepreg
Authors: Sun Liangfeng , Pang Su‐Seng , Sterling Arthur M. , Negulescu Ioan I. , Stubblefield Michael A.
Published: October 2002

The dynamic curing process was studied by using differential scanning calorimetry (DSC) and modeled by two methods. One was based on the Kissinger and Ozawa approach, in which the activation energy was taken as a constant for all the heating rates. The whole curing process was modeled with two cure reactions. Reaction 1 exhibited the behavior of the autocatalytic reaction, whereas Reaction 2 was the nth order reaction. The effect of heating rate on the preexponential factor A1 of Reaction 1 was apparent. As the heating rate increased, the A1 decreased. There was no significant effect of heating rate on the preexponential factor A2 of Reaction 2 and the reaction orders for both reactions. The calculated results showed that the contributions of these two reactions to the total curing process were very different and changed with the heating rate. Except in the early cure stage, the calculated total degree of cure agreed well with the experimental data. Another method was based on the Borchardt and Daniels kinetic approach, where the activation energy of the cure reaction at each heating rate was determined separately. The whole curing process was modeled with one autocatalytic reaction. The fitting results showed that both preexponential factor and activation energy increased with the increment of the heating rate. As in the first method, the effect of heating rate on the orders of reaction was very small. The calculated results agreed well with experimental values in the early cure stage. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 1911–1923, 2002
The influence of the preparing conditions of SiO2 supported Cp2ZrCl2 catalyst on ethylene polymerization
Authors: De Fátima V. Marques Maria , Conte Anunciata
Published: October 2002

In this work, ethylene was polymerized by using Cp2ZrCl2 supported on silica pretreated with methylaluminoxane (MAO) as the catalyst system. The influence of the conditions for the preparation of the heterogeneous catalyst, such as temperature, washing method of the catalytic solid, MAO and metallocene concentration in the support treatment, time of MAO, and metallocene immobilization on the support, type of alkylaluminum used in the support pretreatment, and calcination temperature of the support were investigated. Aluminum and zirconium content fixed on the silica surface were determined by inductively coupled plasma emission spectroscopy. Polymer characteristics were determined by gel permeation chromatography and differential scanning calorimetry. According to the results, the activity of some supported catalysts were far higher than with the homogeneous system. Moreover, polyethylene with very high molecular weights were also obtained and with molecular weight distribution larger than those produced with the homogeneous precursor. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2054–2061, 2002
Environmental stability of electrically conductive viologen–polyaniline systems
Authors: Zhao Baozong , Neoh K. G. , Kang E. T.
Published: October 2002

Viologen–polyaniline (PANI) systems were prepared by PANI being coated onto viologen‐grafted low‐density polyethylene films. PANI in this system could undergo photoinduced doping with ultraviolet irradiation. The electrical stability of the electrically conductive viologen–PANI systems was found to be stable in air, but the conductivity decreased rapidly when the sample was treated in aqueous media of pH > 5 because of the migration of the anions out of PANI into water. However, the conductivity increased by a factor of 2 after treatment in a 1M HCl solution because of the further protonation of PANI by acid. The structural changes of these systems were monitored with ultraviolet–visible absorption spectroscopy, Fourier transform infrared spectroscopy, X‐ray photoelectron spectroscopy, and resistance measurements. The electrical stability of the viologen–PANI system in water could be enhanced via spin coating with poly(methyl methacrylate) (PMMA) because this layer inhibited the migration of the anions out of the system. The photoinduced doping of PANI could be carried out either before or after the spin coating of PMMA. The advantages and limitations of each method were demonstrated. A PMMA coating with a thickness of approximately 10 μm allowed a significant doping level to be achieved within a short period of irradiation and, at the same time, effectively shielded the film from the effects of the aqueous medium. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2099–2107, 2002
Evolution of the biomechanical material properties of the femur
Authors: Erickson Gregory M. , Catanese Joseph , Keaveny Tony M.
Published: October 2002

The biomechanical performance of long bones is dictated by four key factors: element size, element shape, loading conditions, and material properties. Our understanding of the latter of these has been mostly limited to eutherian mammals and birds, which show similarity. Whether their possession of comparable material properties reflects common ancestry or independent evolution is uncertain. In the present analysis, we tested the bending strength, modulus, and failure strains of the femur and its pterygiophore homolog in actinpterygian fish. Sixty‐nine specimens representing basal character states in seven major vertebrate crown clades were tested. These data were then coupled with avian and mammalian data from the literature and analyzed in an evolutionary context using phylogenetic character analysis. Mean values of 188 MPa for yield strength, 22.4 GPa for Young's modulus, and 8,437 μ∈ for yield strain were obtained for the long bones. Analysis of variance (ANOVA) revealed comparable values between clades that span a 30,000‐fold range of body mass. We conclude that material properties of the first long bones 475 million years ago were conserved throughout evolution. Major locomotory challenges to femora during vertebrate evolution were almost solely accomplished by modifications of element size and shape. Anat Rec 268:115–124, 2002. © 2002 Wiley‐Liss, Inc.
Age‐dependent response to insecticides and enzymatic variation in susceptible and resistant codling moth larvae
Authors: Bouvier Jean‐Charles , Boivin Thomas , Beslay Dominique , Sauphanor Benoît
Published: October 2002

Insecticide resistance in the codling moth, Cydia pomonella, partly results from increased metabolic detoxification. The aim of this study was to follow the age variations in larval susceptibility to deltamethrin and teflubenzuron in one susceptible (S) strain, and two resistant (Rv and Rt) ones selected for resistance to deltamethrin and diflubenzuron, respectively. The age variation of the activities of cytochrome P450‐dependent monooxygenase (MFO), glutathione S‐transferases (GST), and esterases in S and both resistant strains were simultaneously investigated. The highest levels of insecticide resistance were recorded in late instars in both resistant strains, although Rv neonates exhibited enhanced resistance to deltamethrin. The involvement of an additional deltamethrin‐specific mechanism of resistance, which could be mainly expressed in early instars, was supported by previous demonstration of a kdr point mutation in the Rv strain. The cross‐resistance between deltamethrin and teflubenzuron indicated the involvement of non‐specific metabolic pathways in resistance to teflubenzuron, rather than target site modification. A positive correlation between enhanced GST activities and deltamethrin resistance suggested that this mechanism might take place into the adaptive response of C. pomonella to pyrethroids treatments. Enhanced MFO activity was recorded in each instar of the two resistant strains compared to the susceptible one. But these activities were not correlated to the responses to deltamethrin nor to teflubenzuron. In the light of these findings, studying age‐dependence of responses to selection is central to the implementation of monitoring tests of resistances, especially if the target instars are difficult to collect in the field. Arch. Insect Biochem. Physiol. 51:55–66, 2002. © 2002 Wiley‐Liss, Inc.
Significance of penetration, excretion, and transovarial uptake to toxicity of three insect growth regulators in predatory lacewing adults
Authors: Medina Pilar , Smagghe Guy , Budia Flor , del Estal Pedro , Tirry Luc , Viñuela Elisa
Published: October 2002

Topical treatment of the predatory lacewing adults, Chrysoperla carnea (Stephens) (Neuroptera: Chrysopidae) before and after the onset of oviposition with diflubenzuron (DFB) at doses based on the maximum field recommended concentration resulted in a total inhibition of egg hatch due to death of the embryo. In contrast, pyriproxyfen (PYR) and tebufenozide (TEB) did not affect fecundity and egg fertility. To explain these differences in toxicity, the patterns of penetration through the cuticle, distribution inside the insect body, and excretion were studied using [14C]‐labeled isotopes of each insect growth regulator (IGR). Penetration of DFB and TEB reached about 16 and 26% in 7 days, whereas 88% of PYR had penetrated in 24 h. However, the rate of excretion for PYR was very high, compared to that of DFB and TEB. Low amounts of absorbed radioactivity were recovered from the female body with the exception of DFB, the ovaries and the eggs deposited during a week. DFB and PYR concentration reached a peak in the eggs deposited at the fourth and second day after treatment, respectively. The current data indicate the importance of penetration through the insect cuticle. However, other mechanisms are likely to be involved in the selectivity of the current IGRs towards this beneficial insect. Arch. Insect Biochem. Physiol. 51:91–101, 2002. © 2002 Wiley‐Liss, Inc.
Organizational measures as a form of knowledge management: A multitheoretic, communication‐based exploration
Authors: Lehr Jennifer K. , Rice Ronald E.
Published: October 2002

One form of knowledge management is the use of measures, to foster learning, to transform individual tacit understanding to shared explicit sensemaking, to evaluate and improve processes and customer service, and even to rationalize and control organizational activities and workers. This article summarizes and applies four theoretical approaches—organizational learning, sensemaking, quality management, and critical theory—to explore how measures are constructed, interpreted, and used within organizational settings as forms of knowledge management. The primary principles, the role of communication, and the role of measures are summarized for each approach. The article ends by discussing some implications of measures in general and this multitheoretic conceptualization of measures in particular for knowledge management.
On the use of compound noise factor in parameter design experiments
Authors: Hou X. Shirley
Published: October 2002

In some applications the cross‐array format for parameter design experiments is too costly to conduct. Instead of using a single array for both control and noise factors, Taguchi proposed a compound noise technique to reduce the size of experiments. It works by selecting a few ‘extreme’ conditions in noise factors and ‘compounding’ them into a single factor. Its performance is investigated through theoretical analysis, simulations, and real experiments. Copyright © 2002 John Wiley & Sons, Ltd.
On the “unreasonable” effects of ELF magnetic fields upon a system of ions
Authors: Giudice E. Del , Fleischmann M. , Preparata G. , Talpo G.
Published: October 2002

A recent experiment on a physical, nonbiological system of ions at room temperature has proved that microscopic ion currents can be induced by applying simultaneously two parallel magnetic fields, one rather weak static field, $\vec B_0$ and one much weaker alternating field, $\vec B_{ac}$, [Bac ∼ 10−3 B0] whose frequency coincides with the cyclotron frequency $v\, = \,qB_0 /2{\pi}m$ of the selected ion. As a result, ionic bursts lasting up to 20 s and with amplitude up to 10 nA arise. The much larger exchanges of energy induced by thermal agitation (the “kT‐problem”) appear to play no role whatsoever. We have analyzed this problem in the framework of coherent quantum electrodynamics, reaching the following conclusions: (a) as has been shown in previous articles, water molecules in the liquid and solute ions are involved in their ground state in coherent ordered configurations; (b) ions are able to move without collisions among themselves in the interstices between water coherence domains; (c) because of coherence, ions can follow classical orbits in the magnetic fields. A full quantitative understanding of the experiments is thus reached. Bioelectromagnetics 23:522–530, 2002. © 2002 Wiley‐Liss, Inc.
Impact of cell culture process changes on endogenous retrovirus expression
Authors: Brorson Kurt , de Wit Christina , Hamilton Elizabeth , Mustafa Mehnaz , Swann Patrick G. , Kiss Robert , Taticek Ron , Polastri Gian , Stein Kathryn E. , Xu Yuan
Published: October 2002

Cell culture process changes (e.g., changes in scale, medium formulation, operational conditions) and cell line changes are common during the development life cycle of a therapeutic protein. To ensure that the impact of such process changes on product quality and safety is minimal, it is standard practice to compare critical product quality and safety attributes before and after the changes. One potential concern introduced by cell culture process improvements is the possibility of increased endogenous retrovirus expression to a level above the clearance capability of the subsequent purification process. To address this, retrovirus expression was measured in scaled down and full production scaled Chinese hamster ovary (CHO) cell cultures of four monoclonal antibodies and one recombinant protein before and after process changes. Two highly sensitive, quantitative (Q)‐PCR‐based assays were used to measure endogenous retroviruses. It is shown that cell culture process changes that primarily alter media components, nutrient feed volume, seed density, cell bank source (i.e., master cell bank vs. working cell bank), and vial size, or culture scale, singly or in combination, do not impact the rate of retrovirus expression to an extent greater than the variability of the Q‐PCR assays (0.2–0.5 log10). Cell culture changes that significantly alter the metabolic state of the cells and/or rates of protein expression (e.g., pH and temperature shifts, NaButyrate addition) measurably impact the rate of retrovirus synthesis (up to 2 log10). The greatest degree of variation in endogenous retrovirus expression was observed between individual cell lines (up to 3 log10). These data support the practice of measuring endogenous retrovirus output for each new cell line introduced into manufacturing or after process changes that significantly increase product‐specific productivity or alter the metabolic state, but suggest that reassessment of retrovirus expression after other process changes may be unnecessary. © 2002 Wiley Periodicals, Inc. Biotechnol Bioeng 80: 257–267, 2002.
Metabolic adaptation of Escherichia coli during temperature‐induced recombinant protein production: 1. Readjustment of metabolic enzyme synthesis
Authors: Hoffmann Frank , Weber Jan , Rinas Ursula
Published: October 2002

The metabolic burden and the stress load resulting from temperature‐induced production of human basic fibroblast growth factor is connected to an increase in the respiratory activity of recombinant Escherichia coli, thereby reducing the biomass yield. To study the underlying changes in metabolic enzyme synthesis rates, the radiolabeled proteom was subjected to two‐dimen‐ sional gel electrophoresis. After temperature‐induction, the cAMP‐CRP controlled dehydrogenases of the pyruvate dehydrogenase complex and the tricarboxylic acid cycle (LpdA and SdhA) were induced four times, reaching a maximum 1 h after the temperature upshift. The more abundant tricarboxylic acid cycle dehydrogenases (Icd and Mdh) were initially produced at reduced rates but regained preshift rates within 30 min. The adenylate energy charge dropped immediately after the temperature upshift but recovered within 1 h. Similar profiles in dehydrogenase synthesis rates and adenylate energy charge were found in a control cultivation of a strain carrying the “empty” parental expression vector. Although both strains exhibited significant differences in growth pattern and respiration rates after the temperature upshift, the adaptation of the energetic state of the cells and the synthesis of enzymes from the energy‐generating catabolic pathway did not seem to be affected by the strong overproduction of the recombinant growth factor. In contrast, the synthesis rates of enzymes belonging to the biosynthetic machinery, e.g., translational elongation factors, decreased more strongly in the culture synthesizing the recombinant protein. In control and producing culture, synthesis rates of elongation factors paralleled the respective growth rate profiles. Thus, cells seem to readjust their metabolic activities according to their energetic requirements and, if necessary, at the cost of their biosynthetic capabilities. © 2002 Wiley Periodicals, Inc. Biotechnol Bioeng 80: 313–319, 2002.
Metabolic adaptation of Escherichia coli during temperature‐induced recombinant protein production: 2. Redirection of metabolic fluxes
Authors: Weber Jan , Hoffmann Frank , Rinas Ursula
Published: October 2002

The impact of temperature‐induced synthesis of human basic fibroblast growth factor (hFGF‐2) in high‐cell‐density cultures of recombinant Escherichia coli was studied by estimating metabolic flux variations. Metabolic flux distributions in E. coli were calculated by means of a stoichiometric network and linear programming. After the temperature upshift, a substantially elevated energy demand for synthesis of hFGF‐2 and heat shock proteins resulted in a redirection of metabolic fluxes. Catabolic pathways like the Embden‐Meyerhof‐Parnas pathway and the tricarboxylic acid (TCA) cycle showed significantly enhanced activities, leading to reduced flux to growth‐associated pathways like the pentose phosphate pathway and other anabolic pathways. Upon temperature upshift, an excess of NADPH was produced in the TCA cycle by isocitrate dehydrogenase. The metabolic model predicted the involvement of a transhydrogenase generating additional NADH from NADPH, thereby increasing ATP regeneration in the respiratory chain. The influence of the temperature upshift on the host's metabolism was investigated by means of a control strain harboring the “empty” parental expression vector. The metabolic fluxes after the temperature upshift were redirected similarly to the production strain; the effects, however, were observed to a lesser extent and with different time profiles. © 2002 Wiley Periodicals, Inc. Biotechnol Bioeng 80: 320–330, 2002.
SMEs and the environment: evaluating dissemination routes and handholding levels
Authors: Friedman Andrew L. , Miles Samantha
Published: October 2002

The Better Business Pack (BBP), a toolkit intended to enable SMEs to develop plans and activities that would lead to environmental and financial benefits, is evaluated. It is found that in spite of high user evaluation of the toolkit in terms of design, user‐friendliness, being up to date and recognition that little effort was required before returns could be achieved, actual financial and environmental achievements were patchy. The BBP was designed as a stand‐alone package that would stimulate SMEs to embark on this path without further support. However, the nature of the dissemination route and the presence of ‘handholding’ support significantly affected success levels. Furthermore the nature of this support was crucial. The most effective support came from pre‐existing networks and opportunities to learn from fellow users, rather than traditional consultancy and other external agency support. Awards for best practice were also found to be of importance. Copyright © 2002 John Wiley & Sons, Ltd and ERP Environment.
Tragedy and catharsis in the wake of the 911 attacks
Authors: Kyle Ken , Angelique Holly
Published: October 2002

We argue that the events of 11 september 2001 (911) should be understood as a tragedy in the Greek sense of the term. Contemporary US views of tragedy typically communicate a sense that little can be done to predict or explain catastrophic events. This leads to feelings of hopelessness and helplessness. Accordingly, traditional US psychological interventions focus upon ameliorative efforts only. In Greek notions of tragedy, however, the hero(ine) has a character flaw that contributes to his/her demise. Lessons are learned, and catharsis results. From the standpoint of the US as a tragic hero, psychological interventions should be both ameliorative and preventative. We contend that this overemphasis on ameliorative work and the limited views of terrorism's root causes are counterproductive. Indeed, we recommend that individual US psychologists and the American Psychological Association leadership engage in both ameliorative efforts and broadly conceived preventative work. Copyright © 2002 John Wiley & Sons, Ltd.
Drug addicts in therapy—changes in life space in the course of one year
Authors: Ravenna Marcella , Hölzl Erik , Kirchler Erich , Palmonari Augusto , Costarelli Sandro
Published: October 2002

In a residential community treatment setting, moods and emotional states of drug addicts were explored over a 1‐year period. The specific form of treatment of heroin addiction employed in the communities is based on the importance of interpersonal relationships for psychosocial transition. Twenty‐nine participants reported current mood, emotions, attributions, and motive activation using a time‐sampling diary for 2 weeks at the beginning of the treatment, and 6 and 12 months later. Results show an increase in positive emotions, and in subjective strength and freedom. Furthermore, participants report higher self‐esteem and use less fatalistic attributions. This is interpreted as indicating successful transition processes in terms of higher autonomy, a more extended life space and increased levels of realism. Copyright © 2002 John Wiley & Sons, Ltd.
A mathematical model for suppression subtractive hybridization
Authors: Gadgil Chetan , Rink Anette , Beattie Craig , Hu Wei‐Shou
Published: October 2002

Suppression subtractive hybridization (SSH) is frequently used to unearth differentially expressed genes on a whole‐genome scale. Its versatility is based on combining cDNA library subtraction and normalization, which allows the isolation of sequences of varying degrees of abundance and differential expression. SSH is a complex process with many adjustable parameters that affect the outcome of gene isolation. We present a mathematical model of SSH based on DNA hybridization kinetics for assessing the effect of various parameters to facilitate its optimization. We derive an equation for the probability that a particular differentially expressed species is successfully isolated and use this to quantify the effect of the following parameters related to the cDNA sample: (a) mRNA abundance; (b) partial sequence complementarity to other species; and (3) degree of differential expression. We also evaluate the effect of parameters related to the process, including: (a) reaction times; and (b) extent of driver excess used in the two hybridization reactions. The optimum set of process parameters for successful isolation of differentially expressed species depends on transcript abundance. We show that the reaction conditions have a significant effect on the occurrence of false‐positives and formulate strategies to isolate specific subsets of differentially expressed genes. We also quantify the effect of non‐specific hybridization on the false‐positive results and present strategies for spiking cDNA sequences to address this problem. Copyright © 2002 John Wiley & Sons, Ltd.
Age specific and attributable risks of familial prostate carcinoma from the family‐cancer database
Authors: Hemminki Kari , Czene Kamila
Published: October 2002

BACKGROUND

Familial risks by proband status and age are useful for clinical counseling, and they can be used to calculate population‐attributable fractions (PAFs), which show the proportion of disease that could be prevented if the cause could be removed.

METHODS

The authors used the nationwide Swedish Family‐Cancer Database on 10.2 million individuals and 182,104 fathers and 3710 sons with medically verified prostate carcinoma to calculate age specific familial standardized incidence ratios (SIRs) with 95% confidence intervals (95%CI) and familial PAFs for prostate carcinoma in sons ages 0–66 years.

RESULTS

The incidence of prostate carcinoma was doubled between the years 1961 and 1998. The familial SIRs for prostate carcinoma were 2.38 (95%CI, 2.18–2.59) for men with prostate carcinoma in the father only, 3.75 (95%CI, 2.73–4.95) for men with prostate carcinoma in a brother only, and 9.44 (95%CI, 5.76–14.03) for men with prostate carcinoma in both a father and a brother. The corresponding familial PAFs were 8.86%, 1.78%, and 0.99%, respectively, yielding a total PAF of 11.63%. Age specific risks were shown for the same proband histories. The SIR was 8.05 for prostate carcinoma before age 55 if a brother had been diagnosed before that age. If, in addition, a father was diagnosed at any age, then the SIR was 33.09.

CONCLUSIONS

The authors recommend that having a brother who is diagnosed with prostate carcinoma before age 55 years or having a brother and father who are diagnosed at any age are indications to screen for prostate carcinoma. The familial PAF of prostate carcinoma among a population of sons ages 0–66 years was 11.63%. Cancer 2002;95:1346–53. © 2002 American Cancer Society.

DOI 10.1002/cncr.10819
Improving the efficiency of finite element formulations in laminated composites
Authors: Soldatos Kostas P. , Shu Xiaoping
Published: October 2002

This communication extends the principles of an advanced smeared laminate plate theory towards the development of corresponding FE models and codes. The present FE numerical results are compared with those based on exact elasticity solutions, as well as those of corresponding FE models based on three conventional laminate plate theories. These comparisons show that, compared to those conventional FE codes, the proposed FE formulation that uses also a small and fixed number of nodal degrees of freedom improves substantially the accuracy of stress predictions. They also show that the present numerical results are particularly accurate even for very thick laminates. Copyright © 2002 John Wiley & Sons, Ltd.
Bandwidth‐efficient turbo coding over Rayleigh fading channels
Authors: Le Goff Stéphane Y.
Published: October 2002

Introduced in 1993, turbo codes can achieve high coding gains close to the Shannon limit. In order to design power and bandwidth‐efficient coding schemes, several approaches have been introduced to combine high coding rate turbo codes with multilevel modulations. The coding systems thus obtained have been shown to display near‐capacity performance over additive white Gaussian noise (AWGN) channels. For communications over fading channels requiring large coding gain and high bandwidth efficiency, it is also interesting to study bit error rate (BER) performance of turbo codes combined with high order rectangular QAM modulations. To this end, we investigate, in this paper, error performance of several bandwidth‐efficient schemes designed using the bit‐interleaved coded modulation approach that has proven potentially very attractive when powerful codes, such as turbo codes, are employed. The structure of these coding schemes, termed ‘bit‐interleaved turbo‐coded modulations’ (BITCMs), is presented in a detailed manner and their BER performance is investigated for spectral efficiencies ranging from 2 to 7 bit/s/Hz. Computer simulation results indicate that BITCMs can achieve near‐capacity performance over Rayleigh fading channels, for all spectral efficiencies considered throughout the paper. It is also shown that the combination of turbo coding and rectangular QAM modulation with Gray mapping constitutes inherently a very powerful association, since coding and modulation functions are both optimized for operation in the same signal‐to‐noise ratio region. This means that no BER improvement is obtainable by employing any other signal constellation in place of the rectangular ones. Finally, the actual influence of the interleaving and mapping functions on error performance of BITCM schemes is discussed. Copyright © 2002 John Wiley & Sons, Ltd.
A numerical method to solve the m‐terms of a submerged body with forward speed
Authors: Duan W.‐Y. , Price W. G.
Published: October 2002

To model mathematically the problem of a rigid body moving below the free surface, a control surface surrounding the body is introduced. The linear free surface condition of the steady waves created by the moving body is satisfied. To describe the fluid flow outside this surface a potential integral equation is constructed using the Kelvin wave Green function whereas inside the surface, a source integral equation is developed adopting a simple Green function. Source strengths are determined by matching the two integral equations through continuity conditions applied to velocity potential and its normal derivatives along the control surface. After solving for the induced fluid velocity on the body surface and the control surface, an integral equation is derived involving a mixed distribution of sources and dipoles using a simple Green function and one component of the fluid velocity. The normal derivatives of the fluid velocity on the body surface, namely the m‐terms, are then solved by this matching integral equation method (MIEM).

Numerical results are presented for two elliptical sections moving at a prescribed Froude number and submerged depth and a sensitivity analysis undertaken to assess the influence of these parameters. Furthermore, comparisons are performed to analyse the impact of different assumptions adopted in the derivation of the m‐terms. It is found that the present method is easy to use in a panel method with satisfactory numerical precision. Copyright © 2002 John Wiley & Sons, Ltd.
Case‐control study of genetic and environmental influences on premature death of adult adoptees
Authors: Petersen Liselotte , Nielsen Gert G. , Andersen Per Kragh , Sorensen Thorkild I. A.
Published: October 2002

Genetic and environmental influence on risk of premature death in adulthood was investigated by estimating the associations in total and cause‐specific mortality of adult Danish adoptees and their biological and adoptive parents. Among all 14,427 nonfamilial adoptions formally granted in Denmark during the period 1923 through 1947, we identified 976 case families in which the adoptee died before a fixed date. As control families, we selected 976 families where the adoptees were alive on that date, and matched to the case adoptees with regard to gender and year and month of birth. The data were viewed as a cohort of case parents and a cohort of control parents, and lifetime distributions in the two cohorts were compared using a Cox regression, stratified with regard to the matching variables: gender and year of birth. In the main analyses, the sample was restricted with regard to birth year of the adoptees, and age of transfer to the adoptive parents, and age at death was restricted to the same range for parents and offspring (25–64 years) in order to consider a symmetric lifetime distribution. This reduces the sample to 459 case families and 738 control families. Various truncations, restrictions, and stratifications were used in order to examine the robustness of the results. The results showed a higher mortality among biological parents who had children dying in the age range 25 through 64 years, and this was significant for death from natural causes, infectious causes, vascular causes, and from all causes combined. There were no significant effects for the adoptive parents. This study supports that there are moderate genetic influences on the risk of dying prematurely in adulthood, and only a small, if any, effect of the family environment. Genet. Epidemiol. 23:123–132, 2002. © 2002 Wiley‐Liss, Inc.
Development of the Korean version of Alzheimer's Disease Assessment Scale (ADAS‐K)
Authors: Youn J. C. , Lee D. Y. , Kim K. W. , Lee J. H. , Jhoo J. H. , Lee K. U. , Ha J. , Woo J. I.
Published: October 2002

Objective

The purpose of this study was the development of the Korean Version of Alzheimer's Disease Assessment Scale (ADAS‐K).

Method

ADAS‐K was administrated to 84 AD patients as well as 105 non‐demented control subjects. Three aspects of reliability were tested. To evaluate the validity of ADAS‐K, discriminant validity and concurrent validity were tested. To evaluate the sensitivity of ADAS‐K to disease severity, all subjects, AD patients and control subjects, were grouped by CDR scale and their mean scores on ADAS‐K were compared.

Result

ADAS‐K demonstrated high levels of reliability. Mean ADAS‐K scores for AD patients were significantly different from the control group (p < 0.01). Furthermore, ADAS‐K exhibited significant correlations with other tests and scales (range 0.45–0.85, p < 0.01). In ROC curve analysis, ADAS‐K displayed high diagnostic efficacy and the optimal cut‐off point was selected between 18/19. ADAS‐K was able to discriminate the degree of AD severity according to CDR classification. Our results suggested that ADAS‐K‐cog was sensitive to very mild AD.

Conclusion

We demonstrated that ADAS‐K is a reliable and valid instrument not only for AD diagnosis but also for evaluation of its severity. Copyright © 2002 John Wiley & Sons, Ltd.
Science for all Americans
Authors: Nelson George D.
Published: October 2002

Setting goals for student learning in fields of science, technology, and mathematics must receive institutionwide attention, setting expectations for what graduates should know and developing departmental and programmatic course offerings that ensure those expectations will be met.
A multidisciplinary core corriculum
Authors: Jordan Trace
Published: October 2002

A major research university makes a commitment to give students not majoring in science or engineering a solid foundation in scientific and quantitative thinking through an integrated large‐scale, multidisciplinary three‐course sequence.
Linking departmental and institutional mission
Authors: Haynes J. K.
Published: October 2002

Mission statements at the departmental level can frame strategic planning and assessment efforts, build community, and focus teaching and research activities.
Investing in digital resources
Authors: McArthur David
Published: October 2002

Technology‐driven transformations of the learning environment are here to stay, and there is no alternative to precise planning to ensure that they serve larger institutional goals over the long term.
The variables of positive change
Authors: Sullivan Daniel F.
Published: October 2002

Systematic reform of undergraduate science and mathematics education requires that faculty innovators and administrative leaders work together.
The role of the grants officer
Authors: Willard Lee W.
Published: October 2002

A key player in the institutional effort to build and sustain strong undergraduate STEM programs is the grants officer, who knows where and how to secure the external gifts and grants essential to accomplishing strategic initiatives.
Fund development for science facilities
Authors: Appleton James R.
Published: October 2002

A president reviews the critical elements of a capital campaign program.
Malignant tumors of the nasal cavity and paranasal sinuses
Authors: Katz Teri S. , Mendenhall William M. , Morris Christopher G. , Amdur Robert J. , Hinerman Russell W. , Villaret Douglas B.
Published: October 2002

Purpose

To evaluate the role of radiation therapy in patients with nasal cavity and paranasal sinus tumors.

Materials and Methods

Between October 1964 and July 1998, 78 patients with malignant tumors of the nasal cavity (48 patients), ethmoid sinus (24 patients), sphenoid sinus (5 patients), or frontal sinus (1 patient) were treated with curative intent by radiation therapy alone or in the adjuvant setting. There were 25 squamous cell carcinomas, 14 undifferentiated carcinomas, 31 minor salivary gland tumors (adenocarcinoma, adenoid cystic carcinoma, and mucoepidermoid carcinoma), 8 esthesioneuroblastomas, and 1 transitional cell carcinoma. Forty‐seven patients were treated with irradiation alone, 25 with surgery and postoperative irradiation, 2 with preoperative irradiation and surgery, and 4 with chemotherapy in combination with irradiation with or without surgery.

Results

The 5‐year actuarial local control rate for stage I (limited to the site of origin; 22 patients) was 86%; for stage II (extension to adjacent sites (eg, adjacent sinuses, orbit, pterygomaxillary fossa, nasopharynx; 21 patients) was 65%; and for stage III (destruction of skull base or pterygoid plates, or intracranial extension; 35 patients) was 34%. The 5‐year actuarial local control rate for patients receiving postoperative irradiation was 79% and for patients receiving irradiation alone was 49% (p = .05). The 5‐, 10‐, 15‐, and 20‐year ultimate local control rates for all 78 patients were 60%, 56%, 48%, and 48%, respectively. The 5‐, 10‐, 15‐, and 20‐year cause‐specific survival rates for all 78 patients were 56%, 45%, 39%, and 39%, respectively. The 5‐, 10‐, 15‐, and 20‐year absolute survival rates for all 78 patients were 50%, 31%, 21%, and 16%, respectively. Of the 67 (86%) patients who were initially seen with node‐negative disease, 39 (58%) received no elective neck treatment, and 28 (42%) received elective neck irradiation. Of the 39 patients who received no elective neck treatment, 33 (85%) did not experience recurrence in the neck compared with 25 (89%) of 28 patients who received elective neck irradiation. Most patients who received elective neck irradiation (57%) had stage III disease. Twenty‐one (27%) of 78 patients had unilateral blindness develop secondary to radiation retinopathy or optic neuropathy; the complication was anticipated in most of these patients, because the ipsilateral eye was irradiated to a high dose. Four patients (5%) unexpectedly had bilateral blindness develop because of optic neuropathy. All four of these patients received irradiation alone.

Conclusion

Surgery and postoperative radiation therapy may result in improved local control, absolute survival, and complications when compared with radiation therapy alone. Elective neck irradiation is probably unnecessary for patients with early‐stage disease. © 2002 Wiley Periodicals, Inc. Head Neck 24: 821–829, 2002
HR Professionals' beliefs about effective human resource practices: correspondence between research and practice
Authors: Rynes Sara L. , Colbert Amy E. , Brown Kenneth G.
Published: October 2002

Five thousand human resource (HR) professionals were surveyed regarding the extent to which they
agreed with various HR research findings. Responses from 959 participants suggest that there are large
discrepancies between research findings and practitioners' beliefs in some content areas, especially
selection. In particular, practitioners place far less faith in intelligence and personality tests as predictors
of employee performance than HR research would recommend. Practitioners are somewhat more likely to agree with
research findings when they are at higher organizational levels, have SPHR certification, and read the academic
literature. Suggestions are made for more effective dissemination of HR research findings. © 2002 Wiley
Periodicals, Inc.