bluuebunny/crossref_metadata_2025 huggingface dataset:
Tensile elongation of high‐fluid polypropylene/ethylene–propylene rubber blends: Dependence on molecular weight of the components and propylene content of the rubber
Authors: Naiki Masahiro , Matsumura Takenobu , Matsuda Masatoshi
Published: August 2002

We studied tensile behavior of low‐molecular‐weight (MW) polypropylene (PP)/ethylene–propylene rubber (EPR; 70/30) blends from the viewpoint of the MWs of PP and EPR and the compatibility between PP and EPR. The value of the melt flow rate of PP varied from 30 to 700 g/10 min at 230°C. We studied the compatibility between PP and EPR by varying the propylene content in EPR (27 and 68 wt %). At the initial elongation stage, crazes were observed in all blends. When blends included EPR with 27 wt % propylene, the elongation at break of the low‐MW PP improved little. The blends with EPR and 68 wt % propylene content were elongated further beyond their yielding points. The elongation to rupture was increased with increasing MW of EPR. Molecular orientation of the low‐MW PP was manifested by IR dichroism measurements and X‐ray diffraction patterns. The blends of low‐MW PP and EPR could be elongated by the partial dissolution of EPR of high‐MW in the PP amorphous phase. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 46–56, 2002
Dynamic mechanical signatures of a polyester‐urethane and plastic‐bonded explosives based on this polymer
Authors: Hoffman D. Mark
Published: August 2002

The complex shear moduli of the segmented polyurethane Estane 5703p, Livermore explosive (LX)‐14, and plastic bonded explosive (PBX)‐9501, which use this polymer as a binder, have been investigated. Segmented polyurethanes, such as Estane 5703, contain microphase‐separated hard segments in a rubbery matrix of soft segments. LX‐14 is composed of 95.5% 1,3,5,7‐tetranitroazacyclooctane (HMX) explosive with 4.5% Estane 5703 binder. PBX‐9501 is composed of 94.9% HMX, 2.5% Estane 5703p binder, 2.5% nitroplasticizer (NP), and about 0.1% antioxidant Irganox 1010. In the temperature range from −150 to 120°C, two relaxations were observed as peaks in the loss modulus and tangent delta in Estane 5703p and LX‐14. A third relaxation was found in PBX‐9501. The low temperature relaxation associated with vitrification of the poly(ester urethane) soft segment occurred in the shear loss modulus (G″) at −29 and −26°C in Estane and LX‐14, respectively, at 1 Hz. In PBX‐9501 the Estane soft segment glass transition peak, Tg(SS), in the loss modulus occurred at −40 ± 3°C at 1 Hz. The reduction in soft segment glass transition in PBX‐9501 is clear evidence of plasticization of the soft segment by NP. The apparent activation energy of the maximum in the loss modulus for LX‐14 and PBX‐9501 over the frequency range from 0.1 to 10 Hz was 230 kJ/mole (55 kcal/mole). The hard segment glass transition, Tg(HS), was observed as a peak in the loss modulus at about 70°C. In LX‐14 the transition was observed at lower temperatures (56–58°C at 1 Hz) depending on thermal history. There was a low temperature shoulder on the Tg(HS) of Estane 5703 associated with soft segment crystallinity. Modulated differential scanning calorimetry (MDSC) was used to verify the Tg(HS) in Estane and 50/50 mixtures of Estane with NP. In PBX‐9501 the hard segment glass transition occurred between 65 and 72°C. The presence of NP in PBX‐9501 gave rise to a new transition, Teu(NP), between 8 and 15°C. This peak is believed to be associated with the eutectic melting of the plasticizer. Returns of fielded PBX‐9501 that were 6 and 11 years old were also measured. Small variations in Tg(SS) and the rubber plateau modulus were observed in these aged samples, consistent with migration of plasticizer and/or very low levels of chain scission. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 1009–1024, 2002
Polycarboxylic acids as crosslinking agents for grafting cyclodextrins onto cotton and wool fabrics: Study of the process parameters
Authors: Martel B. , Weltrowski M. , Ruffin D. , Morcellet M.
Published: August 2002

In this paper we describe a new method for the grafting of cyclodextrins (CDs)onto cotton or wool fabrics. The novelty principally concerns the chemical approach of the grafting reaction that was carried out in the presence of polycarboxylic acids, such as 1,2,3,4‐butanetetracarboxylic acid, citric acid, or polyacrylic acid. All types of native or CD derivatives could be used successfully as long as they carried enough remaining hydroxyl groups. For example, the amount of native β‐CD fixed onto the fabrics increased up to 12% in weight, whereas this value decreased to only 3% for the randomly methylated derivative of β‐CD (RAMEB). We observed that phosphorous salts, such as sodium mono‐ and dihydrogen phosphate or sodium dihydrogen hypophosphite, catalyzed the reaction. On the other hand, the conventional and convenient pad–dry–cure technique that is currently used at the industrial scale in textile processing was applied. We report that the polycarboxylic acids play the role of linking agent through an esterification (or amidification) reaction with the OH (or NH2) groups of both CD and cotton (or wool) fibers. In addition, this reaction could lead to the graft of a copolymer formed between CD and the polycarboxylic acid. The reaction yield depends on the concentration and nature of the aforementioned reactants and catalysts and on the curing conditions (time and temperature). © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 1449–1456, 2002
Some effects of marine reserve protection on the population structure of two spearfishing target‐fish species, Dicentrarchus labrax (Moronidae) and Sparus aurata (Sparidae), in shallow inshore waters, along a rocky coast in the northwestern Mediterranean Sea
Authors: Jouvenel J.‐Y. , Pollard D.A.
Published: August 2002

1. The relative abundances of two highly sought after spearfishing target‐fish species, Dicentrarchus labrax (Linnaeus 1758) and Sparus aurata Linnaeus 1758, were compared using underwater visual censuses in shallow (<5 m) inshore waters along rocky shores inside and outside a marine reserve area in the northwestern Mediterranean Sea (Banyuls‐sur‐Mer region, France).

2. The relative abundances of these two species were consistently lower outside the reserve area, which comprised around 40% of the 25.6 km of inshore coastal waters surveyed.

3. The demographic structure of D. labrax was also different inside and outside the protected area, the proportion of larger fish being significantly higher in the marine reserve.

4. The direct and indirect impacts of spearfishing are postulated to explain the distributional and population structural characteristics of these two species in the shallow waters off this rocky coast.

5. Prohibition of spearfishing has favoured the persistence of these species during summer (the main spearfishing season) in the shallower inshore waters inside the area of the Cerbère/Banyuls‐sur‐Mer marine reserve.

6. These preliminary results indicate the need for additional work in this area and further surveys to ascertain spearfishing impacts on target‐fish species in the vicinity of other marine protected areas.

Copyright © 2001 John Wiley & Sons, Ltd.
Acetylcholine receptors and nerve terminal distribution at the neuromuscular junction of non‐obese diabetic mice
Authors: Marques Maria Julia , Neto Humberto Santo
Published: August 2002

Skeletal muscle is one of the main targets of the metabolic alterations in diabetes, in which protein synthesis is markedly reduced followed by increased proteolysis. Ultrastructural and functional changes in the presynaptic compartment of the neuromuscular junction (NMJ) have been demonstrated, but little attention has been paid to the proteins in the postsynaptic muscle fiber membrane. In the present work, we studied the changes in acetylcholine receptors (AChRs) and nerve terminal distribution in the NMJ of non‐obese diabetic (NOD) mice. The sternomastoid muscles of adult female NOD mice were double‐labeled for AChR and nerve terminal observation by fluorescence and reflected light confocal microscopy. In 62.4% of the diabetic endplates, AChR branches broke apart into receptor islands that stained less than in the normal mice. These patches had regular junctional folds. At most of the endplates studied, the nerve terminals colocalized with AChRs, and sprouts were seen in 10% of the diabetic endplates. The intramuscular nerve branches and axons in the nerve to the sternomastoid muscle showed no degenerative disorders. These results suggest that metabolic alterations in the diabetic muscle fiber can affect the distribution and expression of molecules, such as AChRs, in the postsynaptic membrane of the neuromuscular junction. Anat Rec 267:112–119, 2002. © 2002 Wiley‐Liss, Inc.
Limb myosin heavy chain isoproteins and muscle fiber types in the adult goat (Capra hircus)
Authors: Argüello Anastasio , López‐Fernández Juan‐Luis , Rivero José‐Luis L.
Published: August 2002

The primary focus of this study was the accurate classification of limb skeletal muscle fiber types in adult goats (Capra hircus) according to the myosin heavy chain (MHC) isoform they express. Combined methodologies of gel electrophoresis, immunoblotting, immunohistochemistry, myofibrillar ATPase (mATPase), and quantitative metabolic enzyme histochemistry of M. semitendinosus samples were developed. Three MHCs were identified and tentatively designated as types I, IIA, and IIX. Five fiber types were defined immunohistochemically according to their MHC content: I, I+IIA, IIA, IIAX, and IIX. The hybrid fast‐twitch fibers (IIAX) totaled 21% of the fiber population analyzed. The three major pure fibers (I, IIA, and IIX) could be objectively separated upon the basis of their mATPase activities after acid and alkaline preincubations. The prominent number of hybrid fibers, however, could not be delineated with these mATPase methods. Metabolic and size properties of muscle fibers varied according to their MHC content, but overlapped the full range of muscle fiber phenotypes. These integrated data demonstrate that type II skeletal muscle fibers of small ruminants have been misclassified in previous studies. The immunohistochemical approach developed in the present study offers new prospects for muscle fiber typing in caprine experimental studies and meat production technologies. Anat Rec 264:284–293, 2001. © 2001 Wiley‐Liss, Inc.
Resistivity imaging of the linear earthworks at the Mull of Galloway, Dumfries and Galloway
Authors: Neighbour T. , Strachan R. , Hobbs B. A.
Published: August 2002

Resistivity imaging was carried out over two linear earthworks that cut off a peninsula at the neck of the Mull of Galloway. The geophysical work formed part of a wider research programme, funded by Historic Scotland, involving excavation and survey, designed to assess the extent of erosion to the site. The southern (inner) line of earthworks is ca. 440 m long, whereas the northern (outer) earthwork measures only ca. 120 m. Both survive as turf and gorse covered, upstanding banks and ditches. Four resistivity images were taken across the earthworks. A further image was placed just to the south of the southern earthwork in an attempt to trace cobbles identified during excavation. The surveys used a Geopulse Imager system with 25 electrodes and an interelectrode spacing of 1 m, and apparent resistivities were acquired with the Wenner configuration. Topographic corrections were applied to the 22‐m‐long pseudosections, which were then inverted using Res2DInv to obtain resistivity models. Excavation of trenches through the earthworks confirmed that the resistivity models had been successful in providing an accurate picture of the character and construction of these rampart and ditch systems. Copyright © Crown Copyright 2001. Recorded with the permission of the controller of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd.
The effects of progressive strength training and aerobic exercise on muscle strength and cardiovascular fitness in women with fibromyalgia: A pilot study
Authors: Rooks Daniel S. , Silverman Caroline B. , Kantrowitz Fred G.
Published: August 2002

Objective

To determine the safety, feasibility and consequences of a program of progressive strength training and cardiovascular exercise in women with fibromyalgia syndrome (FMS).

Methods

Fifteen women with confirmed FMS were monitored for injury and exercise compliance, and assessed for muscle strength (1‐repetition maximum technique), cardiovascular endurance (6‐minute walk test), and functional status (Fibromyalgia Impact Questionnaire [FIQ]) before and after a 20‐week exercise intervention.

Results

Zero injuries and an 81% compliance rate occurred during training. Improvement was seen in muscle strength of the lower (191 ± 75 to 265 ± 67 pounds;P< 0.001) and upper (61 ± 18 to 76 ± 18 pounds;P< 0.001) body, 6‐minute walk distance (530 ± 80 to 629 ± 74 meters;P< 0.001), and in FIQ score (44 ± 9 to 32 ± 14;P< 0.01).

Conclusion

A program of progressive strength training and cardiovascular exercise can be safe, well tolerated, and effective at improving muscle strength, cardiovascular endurance and functional status in women with FMS without exacerbating symptoms. This program may also contribute to a reduction in the severity of several symptoms.
Structural effect of avocado/soybean unsaponifiables on joint space loss in osteoarthritis of the hip
Authors: Lequesne Michel , Maheu Emmanuel , Cadet Christian , Dreiser Renèe‐Liliane
Published: August 2002

Objective

To evaluate the structural effect of avocado/soybean unsaponifiables (ASU) in the treatment of patients with symptomatic osteoarthritis (OA) of the hip.

Methods

Patients with regular painful primary OA of the hip (European League Against Rheumatism 1980 criteria) and a joint space still ≥ 1 mm (Kellgren grade 1 to 3, assessed by an independent observer prior to inclusion) entered a prospective, multicenter, randomized, parallel group, double‐blind, placebo‐controlled trial of 2 years duration. Patients had at least a 6‐month history of regular pain and an algofunctional index (AFI) ≥ 4. The primary assessment criterion was a decrease of the joint space width (JSW) on plain anteroposterior radiographs of the pelvis performed in standing position, measured at the narrowest points by 2 independent readers, previously tested and selected and blinded to both the treatment and the time sequence. Secondary criteria were standard clinical outcome measurements (AFI, pain on a visual analog scale, consumption of nonsteroidal antiinflammatory drugs and patient's and investigator's global assessments).

Results

One hundred sixty‐three patients were included: 102 men and 61 women (mean age 63.2 ± 8.7 years). A total of 108 patients (72 men and 36 women; mean age 64 ± 7.9 years) were radiologically evaluable at 23.7 ± 2.6 months (ASU group; n = 55) and 23.7 ± 3.2 months (placebo group; n = 53). Overall comparison of the evolution of JSW showed no difference between the ASU and placebo groups, from 2.35 ± 0.93 to 1.87 ± 1.10 mm and from 2.5 ± 0.94 to 1.9 ± 1.33 mm, respectively (intergroup P value at end point = 0.9). When patients were divided into 2 subgroups according to the median value of the baseline JSW (2.45 mm), the joint space loss in the most severely affected subgroup of patients (baseline JSW ≤ median) was significantly greater in the placebo group than in the ASU group: from 1.69 ± 0.58 to 0.84 ± 0.77 mm (−0.86 ± 0.62 mm) and from 1.66 ± 0.42 to 1.22 ± 0.7 mm (−0.43 ± 0.51 mm), respectively (P < 0.01). The JSW decrease was identical, with no difference in ASU and placebo groups, in the less severely affected subgroup of patients (baseline JSW > median). Clinical parameters in the 2 groups did not differ significantly throughout the study.

Conclusion

This pilot randomized, double‐blind, placebo‐controlled trial failed to demonstrate a structural effect of ASU in hip OA. However, in a post‐hoc analysis, ASU significantly reduced the progression of joint space loss as compared with placebo in the subgroup of patients with advanced joint space narrowing. These results suggest that ASU could have a structural effect but require confirmation in a larger placebo‐controlled study in hip OA.
Getting answers to natural language questions on the Web
Authors: Radev Dragomir R. , Libner Kelsey , Fan Weiguo
Published: August 2002

Most popular search engines are not designed for answering natural language questions. However, when we asked hundreds of natural language questions of nine leading search engines, all retrieved at least one correct answer on more than three‐quarters of the questions. We identified the best‐performing search engines overall for factual natural language questions. We found performance differences depending on the domain of factual question asked. Other aspects of questions also predicted significantly different performance: the number of words in the question, the presence of a proper noun, and whether the question is time dependent. An additional analysis tested for differential performance by specific search engines on these four question factors. The analysis found no evidence for such interactions.
Seeking explanation in theory: Reflections on the social practices of organizations that distribute public use microdata files for research purposes
Authors: Robbin Alice , Koball Heather
Published: August 2002

Public concern about personal privacy has recently focused on issues of Internet data security and personal information as big business. The scientific discourse about information privacy focuses on the crosspressures of maintaining confidentiality and ensuring access in the context of the production of statistical data for public policy and social research and the associated technical solutions for releasing statistical data. This article reports some of the key findings from a small‐scale survey of organizational practices to limit disclosure of confidential information prior to publishing public use microdata files, and illustrates how the rules for preserving confidentiality were applied in practice. Explanation for the apparent deficits and wide variations in the extent of knowledge about statistical disclosure limitation (SDL) methods is located in theories of organizational life and communities of practice. The article concludes with suggestions for improving communication between communities of practice to enhance the knowledge base of those responsible for producing public use microdata files.
Bayesian‐type count data models with varying coefficients: estimation and testing in the presence of overdispersion
Authors: Fahrmeir Ludwig , Mayer Jochen
Published: August 2002

In this paper we study varying‐coefficient models for count data. A Bayesian approach is taken to model the variability of the regression parameters. Based on a Kalman filter procedure the varying coefficients are estimated as the mode of the posterior distribution. All hyperparameters, including an overdispersion parameter in the negative binomial varying‐coefficient model (NBVC), are estimated as ML‐estimators using an EM‐type algorithm. A bootstrapping test of the fixed‐coefficient hypothesis against a varying‐coefficient alternative is proposed, which is evaluated running a simulation study. The study shows that the choice of a suitable count data model is of special importance in the framework of varying‐coefficient models. The methodology is illustrated analysing the determinants of the number of individual doctor visits. Copyright © 2001 John Wiley & Sons, Ltd.
Stock timing using genetic algorithms
Authors: Korczak J. , Roger P.
Published: August 2002

In this paper, a genetic algorithm to search a set of technical trading rules which gives buying and selling advices about individual stocks is proposed. This approach is tested out of a sample of 24 French stocks among the most important stocks traded on the French market. We show that in most cases, the method outperforms a simple buy and hold strategy. However, we also illustrate the fact that the near‐optimal set of rules varies through time and across stocks. Copyright © 2002 John Wiley & Sons, Ltd.
Chiral separation by chromatographic and electromigration techniques. A Review
Authors: Gübitz Gerald , Schmid Martin G.
Published: August 2002

This review gives a survey of different chiral separation principles and their use in high‐performance liquid chromatography (HPLC), gas chromatography (GC), supercritical fluid chromatography (SFC), thin‐layer chromatography (TLC), capillary electrophoresis (CE) and capillary electrochromatography (CEC) highlighting new developments and innovative techniques. The mechanisms of the different separation principles are briefly discussed and some selected applications are shown. Copyright © 2001 John Wiley & Sons, Ltd.
GSM phone signal does not produce subjective symptoms
Authors: Koivisto Mika , Haarala Christian , Krause Christina M. , Revonsuo Antti , Laine Matti , Hämäläinen Heikki
Published: August 2002

The influence of pulsed radiofrequency (RF) electromagnetic fields of digital GSM mobile phones (902 MHz, 217 Hz pulse modulation) on subjective symptoms or sensations in healthy subjects were studied in two single‐blind experiments. The duration of the RF exposure was about 60 min in Experiment 1 and 30 min in Experiment 2. Each subject rated symptoms or sensations in the beginning of the experimental session and at the end of both the exposure and the nonexposure conditions. The symptoms rated were headache, dizziness, fatigue, itching or tingling of the skin, redness on the skin, and sensations of warmth on the skin. The results did not reveal any differences between exposure and non‐exposure conditions, suggesting that a 30–60 min exposure to this RF field does not produce subjective symptoms in humans. Bioelectromagnetics 22:212–215, 2001. © 2001 Wiley‐Liss, Inc.
Structure suggests function: the case for synaptic ribbons as exocytotic nanomachines
Authors: Lenzi David , von Gersdorff Henrique
Published: August 2002

Synaptic ribbons, the organelles identified in electron micrographs of the sensory synapses involved in vision, hearing, and balance, have long been hypothesized to play an important role in regulating presynaptic function because they associate with synaptic vesicles at the active zone. Their physiology and molecular composition have, however, remained largely unknown. Recently, a series of elegant studies spurred by technical innovation have finally begun to shed light on the ultrastructure and function of ribbon synapses. Electrical capacitance measurements have provided sub‐millisecond resolution of exocytosis, evanescent‐wave microscopy has filmed the fusion of single 30 nm synaptic vesicles, electron tomography has revealed the 3D architecture of the synapse, and molecular cloning has begun to identify the proteins that make up ribbons. These results are consistent with the ribbon serving as a vesicle “conveyor belt” to resupply the active zone, and with the suggestion that ribbon and conventional chemical synapses have much in common. BioEssays 23:831–840, 2001. © 2001 John Wiley & Sons, Inc.
Influence of benign cellular changes in diagnosis of cervical cancer using IR microspectroscopy
Authors: Romeo Melissa J. , Quinn Michael A. , Burden Frank R. , McNaughton Don
Published: August 2002

IR spectroscopy and principal components analysis (PCA) of endocervical cells and smears diagnosed with benign cellular changes were investigated to determine the influence of these potential confounding variables in the diagnosis of cervical cancer. Spectral differences in all cell and diagnostic types investigated were found in the phosphodiester and carbohydrate regions. However, the spectral differences in other bands were not distinct enough to allow differentiation between groups. The PCA was successfully used to obtain a separation of normal ectocervical smears from normal endocervical cells and smears diagnosed with inflammation, Candida albicans, and bacterial vaginosis. A separation with a slight overlap of abnormal ectocervical smears from normal endocervical cells, inflammation, and bacterial vaginosis was obtained with PCA. Candida was not separated from abnormal ectocervical smears with any success. © 2002 Wiley Periodicals Inc. Biopolymers (Biospectroscopy) 67: 362–366, 2002
One‐step purification, covalent immobilization, and additional stabilization of poly‐His‐tagged proteins using novel heterofunctional chelate‐epoxy supports
Authors: Mateo Cesar , Fernández‐Lorente Gloria , Cortés Estrella , Garcia José L. , Fernández‐Lafuente Roberto , Guisan José M.
Published: August 2002

Epoxy supports covalently immobilize proteins following a two‐step mechanism; that is, the protein is physically adsorbed and then the covalent reaction takes place. This mechanism has been exploited to combine the selectivity of metal chelate affinity chromatography with the covalent immobilization capacity of epoxy supports. In this way, it has been possible to accomplish, in a simple manner, the purification, immobilization, and stabilization of a poly‐His‐tagged protein. To fulfill this objective we developed a new kind of multifunctional epoxy support (chelate epoxy support [CES]), which was tested using a poly‐His‐tagged glutaryl acylase as a model protein (an αβ‐heterodimeric enzyme of significant industrial interest). The selectivity of the immobilization in CES toward poly‐His‐tagged proteins was dependent to a large extent on the density and nature of the chelated metal. The highest selectivity was achieved by using low‐density chelate groups (e.g., 5 μmol/g) and metals with a low affinity (e.g., Co). However, the rate of covalent immobilization of the protein by its reaction with the epoxy groups on the support significantly increased at alkaline pH values. The multipoint attachment to the CES also depended on the reaction time. The immobilization of both glutaryl acylase subunits was achieved by incubation of the enzyme derivative at pH 10 for 24 h, with the best enzyme derivative 100‐fold more stable than the soluble enzyme. By taking advantage of the selectivity properties of the novel support, we were able to immobilize up to 30 mg of protein per gram of modified Eupergit 250 using either pure enzyme or a very crude enzyme extract. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 76: 269–276, 2001.
Catalytic buffers enable positive‐response inhibition‐based sensing of nerve agents
Authors: Russell Alan J. , Erbeldinger Markus , DeFrank Joseph J. , Kaar Joel , Drevon Geraldine
Published: August 2002

We report herein an efficient method to control pH in reactions catalyzed by hydrolytic enzymes, such as the degradation of paraoxon by phosphotriesterase (E.G. 3.1.8.1; OPH), using urease‐catalyzed (E.G. 3.5.1.5) urea hydrolysis as a buffering agent. Given the distinct pH profiles of urease and OPH activities, urease produces base on demand in response to pH drop during paraoxon detoxification. As pH changes, the enzyme activities fluctuate to finally stabilize at a pH “set‐point,” where the rates of acid and base generation are equal. By varying the urease to OPH ratio, various pH “set‐points” ranging between 6.5 and 8.5 were achieved within minutes and could be predicted theoretically. This dynamic approach for pH control was successfully applied to the development of a positive‐response inhibition‐based sensor. © 2002 John Wiley & Sons, Inc. Biotechnol Bioeng 77: 352–357, 2002.
Sustained hydrogen photoproduction by Chlamydomonas reinhardtii: Effects of culture parameters
Authors: Kosourov Sergey , Tsygankov Anatoly , Seibert Michael , Ghirardi Maria L.
Published: August 2002

The green alga, Chlamydomonas reinhardtii, is capable of sustained H2 photoproduction when grown under sulfur‐deprived conditions. This phenomenon is a result of the partial deactivation of photosynthetic O2‐evolution activity in response to sulfur deprivation. At these reduced rates of water‐oxidation, oxidative respiration under continuous illumination can establish an anaerobic environment in the culture. After 10–15 hours of anaerobiosis, sulfur‐deprived algal cells induce a reversible hydrogenase and start to evolve H2 gas in the light. Using a computer‐monitored photobioreactor system, we investigated the behavior of sulfur‐deprived algae and found that: (1) the cultures transition through five consecutive phases: an aerobic phase, an O2‐consumption phase, an anaerobic phase, a H2‐production phase and a termination phase; (2) synchronization of cell division during pre‐growth with 14:10 h light:dark cycles leads to earlier establishment of anaerobiosis in the cultures and to earlier onset of the H2‐production phase; (3) re‐addition of small quantities of sulfate (12.5–50 μM MgSO4, final concentration) to either synchronized or unsynchronized cell suspensions results in an initial increase in culture density, a higher initial specific rate of H2 production, an increase in the length of the H2‐production phase, and an increase in the total amount of H2 produced; and (4) increases in the culture optical density in the presence of 50 μM sulfate result in a decrease in the initial specific rates of H2 production and in an earlier start of the H2‐production phase with unsynchronized cells. We suggest that the effects of sulfur re‐addition on H2 production, up to an optimal concentration, are due to an increase in the residual water‐oxidation activity of the algal cells. We also demonstrate that, in principle, cells synchronized by growth under light:dark cycles can be used in an outdoor H2‐production system without loss of efficiency compared to cultures that up until now have been pre‐grown under continuous light conditions. © 2002 Wiley Periodicals, Inc. Biotechnol Bioeng 78: 731–740, 2002.
Scale‐up of pseudo solid‐phase enzymatic synthesis of α‐methyl glucoside acrylate
Authors: Li Yanzi , Rethwisch David G.
Published: August 2002

The successful scale‐up of the enzymatic synthesis of α‐methyl glucoside acrylate from laboratory‐scale (milliliter) to pilot‐scale (liter) was examined. Specifically, Candida antarctica lipase B (Novozym 435) was used as a biocatalyst to produce α‐methyl glucoside acrylate via the transesterification of α‐methyl glucoside (MG) with vinyl acrylate (VA) using acetone as a solvent. This is a pseudo‐solid‐phase synthesis; only a fraction of the α‐methyl glucoside and the product are soluble in acetone. Molecular sieves were used to remove traces of water in the reaction medium and to increase enzyme stability by removing the acetaldehyde by‐product. A general method was also developed to purify and recover the monoacrylate product from unreacted sugar and undesired diester by a simple crystallization and precipitation process. © 2002 Wiley Periodicals, Inc. Biotechnol Bioeng 79: 15–22, 2002.
Metabolic pre‐conditioning of cultured cells in physiological levels of insulin: Generating resistance to the lipid‐accumulating effects of plasma in hepatocytes
Authors: Chan Christina , Berthiaume François , Washizu Junji , Toner Mehmet , Yarmush Martin L.
Published: August 2002

Understanding the regulation of hepatocyte lipid metabolism is important for several biotechnological applications involving liver cells. During exposure of hepatocytes to plasma, as is the case in extracorporeal bioartificial liver assist devices, it has been reported that hepatic‐specific functions, e.g., albumin and urea synthesis and diazepam removal, are dramatically compromised and hepatocytes progressively accumulate cytoplasmic lipid droplets. We hypothesized that the composition of hepatocyte culture medium significantly affects lipid metabolism during subsequent plasma exposure. Rat hepatocytes were cultured in medium containing either physiological (50 μU/mL) or supra‐physiological (500 mU/mL) insulin levels for 1 week and then exposed to human plasma supplemented with or without amino acids. We found that insulin’s anabolic effects, such as stimulation of triglyceride storage, were carried over from the pre‐conditioning to the plasma exposure period. While hepatocytes cultured in high insulin medium accumulated large quantities of triglycerides during subsequent plasma exposure, culture in low insulin medium largely prevented lipid accumulation. Urea and albumin secretion, as well as the ammonia removal rate, were largely unaffected by insulin but increased with amino acid supplementation. Thus, hepatocyte metabolism during plasma exposure can be modulated by medium pre‐conditioning and supplements added to plasma. © 2002 Wiley Periodicals, Inc. Biotechnol Bioeng 78: 753–760, 2002.
Kinetics and mass‐transfer phenomena in anaerobic granular sludge
Authors: Gonzalez‐Gil G. , Seghezzo L. , Lettinga G. , Kleerebezem R.
Published: August 2002

The kinetic properties of acetate‐degrading methanogenic granular sludge of different mean diameters were assessed at different up‐flow velocities (Vup). Using this approach, the influence of internal and external mass transfer could be estimated. First, the apparent Monod constant (KS) for each data set was calculated by means of a curve‐fitting procedure. The experimental results revealed that variations in the Vup did not affect the apparent KS‐value, indicating that external mass‐transport resistance normally can be neglected. With regard to the granule size, a clear increase in KS was found at increasing granule diameters. The experimental data were further used to validate a dynamic mathematical biofilm model. The biofilm model was able to describe reaction‐diffusion kinetics in anaerobic granules, using a single value for the effective diffusion coefficient in the granules. This suggests that biogas formation did not influence the diffusion‐rates in the granular biomass. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 73: 125–134, 2001.
Metabolic and kinetic analysis of poly(3‐hydroxybutyrate) production by recombinant Escherichia coli
Authors: van Wegen Richard J. , Lee Sang‐Yup , Middelberg Anton P. J.
Published: August 2002

A quantitatively repeatable protocol was developed for poly(3‐hydroxybutyrate) (PHB) production by Escherichia coli XL1‐Blue (pSYL107). Two constant‐glucose fed‐batch fermentations of duration 25 h were carried out in a 5‐L bioreactor, with the measured oxygen volumetric mass‐transfer coefficient (kLa) held constant at 1.1 min−1. All major consumption and production rates were quantified. The intracellular concentration profiles of acetyl‐CoA (300 to 600 μg · g RCM−1) and 3‐hydroxybutyryl‐CoA (20 to 40 μg · g RCM−1) were measured, which is the first time this has been performed for E. coli during PHB production. The kinetics of PHB production were examined and likely ranges were established for polyhydroxyalkanoate (PHA) enzyme activity and the concentration of pathway metabolites. These measured and estimated values are quite similar to the available literature estimates for the native PHB producer Ralstonia eutropha. Metabolic control analysis performed on the PHB metabolic pathway showed that the PHB flux was highly sensitive to acetyl‐CoA/CoA ratio (response coefficient 0.8), total acetyl‐CoA + CoA concentration (response coefficient 0.7), and pH (response coefficient −1.25). It was less sensitive (response coefficient 0.25) to NADPH/NADP ratio. NADP(H) concentration (NADPH + NADP) had a negligible effect. No single enzyme had a dominant flux control coefficient under the experimental conditions examined (0.6, 0.25, and 0.15 for 3‐ketoacyl‐CoA reductase, PHA synthase, and 3‐ketothiolase, respectively). In conjunction with metabolic flux analysis, kinetic analysis was used to provide a metabolic explanation for the observed fermentation profile. In particular, the rapid onset of PHB production was shown to be caused by oxygen limitation, which initiated a cascade of secondary metabolic events, including cessation of TCA cycle flux and an increase in acetyl‐CoA/CoA ratio. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 74: 70–80, 2001.
Capillary electrophoresis of catecholamines with laser‐induced fluorescence intensified charge‐coupled device detection
Authors: Xiong Shaoxiang , Han Huiwan , Zhao Rui , Chen Yi , Liu Guoquan
Published: August 2002

A capillary electrophoresis–laser‐induced fluorescence–intensified charge‐coupled device system was used for the separation and determination of catecholamines. Optimization of derivatization and separation conditions was investigated in order to reach a high separation efficiency and sensitivity. All fluorecein isothiocyanate derivatives of catecholamines were satisfactorily separated within 12 min. The detection limits were in attomole ranges. This method allows determination of catecholamines with high separation efficiencies and sensitivity. Copyright © 2001 John Wiley & Sons, Ltd.

Abbreviations used:

CBQCA

3‐(4‐carboxybenzoyl)‐2‐quinoline carboxaldehyde

CCD

charge‐coupled device

DA

dopamine, E, epinephrine

FITC

fluorescein isothiocyanate

S‐HT

serotoni Lif, laser‐induced fluorescence

NE

noreginephrine.
Synthesis and distribution of glycosaminoglycans in human leukemic B‐ and T‐cells and monocytes studied using specific enzymic treatments and high‐performance liquid chromatography
Authors: Makatsori E. , Karamanos N. K. , Papadogiannakis N. , Hjerpe A. , Anastassiou E. D. , Tsegenidis T.
Published: August 2002

Identification of glycosaminoglycans (GAGs) synthesized by three human leukaemic cell lines—Jurkat (T‐cell leukaemia), Daudi (Burkitt's lymphoma, B‐cell leukaemia) and THP‐1 (acute monocytic leukemia)—and normal peripheral blood mononuclear cells (PBMC) and their distribution among cell membrane and culture medium were studied. GAGs were isolated using ion‐exchange chromatography on DEAE‐Sephacel and their composition and fine chemical structure were studied using high‐performance liquid chromatography with radiochemical detection. All cell lines synthesize chondroitin sulphate (CS) and heparan sulphate (HS) in both cell membrane and culture medium. No hyaluronan was detected using treatment with specific lyases and highly sensitive HPLC methodology. CS is the major secreted GAG in all cell lines tested and the major cell retained GAG in Jurkat and Daudi. HS is the major GAG in the cell membrane of THP‐1. The amounts of distinct GAGs synthesized by all cancer cell lines differ from those produced by normal PBML indicating a major role of GAGs in malignant transformation of human lymphocytes and monocytes. Copyright © 2001 John Wiley & Sons, Ltd.

Abbreviations used:

CS

chondroitin sulphate

GAGs

glycosaminoglycans

HS

heparan sulphate

PBMC

peripheral blood mononuclear cells

PG

proteoglycans PMSF, phenylmethylsulphonyl fluoride
Measuring environmental performance: use of the toxics release inventory (TRI) and other US environmental databases
Authors: Gerde Virginia W. , Logsdon Jeanne M.
Published: August 2002

This article examines the most comprehensive databases that measure US corporate environmental performance that have become available during the 1990s. These include the US Environmental Protection Agency's Toxics Release Inventory (TRI) and databases maintained by Kinder, Lydenberg, Domini, and Co., the Council on Economic Priorities and the Investor Responsibility Research Center. We describe these databases and identify the significant studies on environmental performance in the field of management that use these databases. We indicate three trends that should improve the quality and quantity of publicly available environmental performance data. Copyright © 2001 John Wiley & Sons, Ltd and ERP Environment
The experience of EMAS in three European countries: a cultural and competitive analysis
Authors: Steger Ulrich , Schindel Claudia , Krapf Helga
Published: August 2002

EMAS, the European Eco‐Management and Audit Scheme, has been open for participation for six years now. Looking at registrations per country, a concentration of registrations in northern European countries is evident. The first part of this article investigates potential reasons by applying two popular models. Geert Hofstede's four cultural dimensions are used to explain favourable or unfavourable conditions for EMAS in a country. Michael E. Porter's national diamond is used to investigate determinants for national competitiveness and their influence on environmental management. These two frameworks are applied to Germany as a benchmark and France and Spain as representatives of southern European countries. In the second part of the article conclusions are drawn from this investigation on the influence of national culture, conditions and incentives for EMAS in these countries. Lastly actions for increased participation in EMAS of southern European countries are presented. Copyright © 2002 John Wiley & Sons, Ltd. and ERP Environment
Responsible chain management: a capability assessment framework
Authors: de Bakker Frank , Nijhof André
Published: August 2002

In recent years, increased attention has been paid to issues of responsibility across the entire product lifecycle. Responsible behaviour of organizations in the product chain is dependent on the actions of other parties such as suppliers and customers. Only through co‐operation and close interaction between the different parties involved is it possible to come to a specified form of responsible chain management. Drawing on stakeholder theory and literature on the resource‐based view of the firm, this article presents a framework for assessing the organizational capabilities of responding to claims from internal and external parties. Interpretations of stakeholder interests, integration into business processes, monitoring these processes, and communication with stakeholders are the central processes in this framework. The application of this framework to three cases of responsible chain management illustrates the functioning of the framework as a tool for assessing organizational capabilities. Copyright © 2002 John Wiley & Sons, Ltd. and ERP Environment
Insertion of the tendon of the tibialis anterior muscle in feet with and without hallux valgus
Authors: Brenner Erich
Published: August 2002

The insertion of the tendon of the tibialis anterior muscle may be related to pathologic changes of the foot and, in particular, hallux valgus. Morphologic data should enable evaluation of such a relationship and perhaps offer a basis for improved therapy. One hundred fifty‐six embalmed feet, including 27 with hallux valgus, were examined. The tendon of the tibialis anterior muscle was dissected and measurements were made, including the width of the insertion on the first metatarsal and medial cuneiform. Distal‐superficial and proximal‐deep slips of the tendon twisted around each other. Two specimens presented with an insertion only on the medial cuneiform; in two other cases the insertion was limited to the first metatarsal; in one case the tendon inserted into the navicular and the medial cuneiform; in all other cases, the tendon inserted into the medial cuneiform and first metatarsal. The insertion was mainly located along the plantar margin of the medial side of the foot; some of the proximal‐deep fibers also passed onto the plantar surface. Fibers inserting on the first metatarsal bone can outwardly rotate the first ray, which is opposite to the inward rotation of the first ray in hallux valgus. In all feet with hallux valgus these fibers were present. Therefore, it is unlikely that this deformity develops because of a specific type of insertion of the tendon of the tibialis anterior muscle, and any therapeutic approach altering the attachment of the tibialis anterior tendon would cause no biomechanical improvement. Clin. Anat. Month:217–223, 2002. © 2002 Wiley‐Liss, Inc.
Phrenic paresis—a possible additional spinal cord dysfunction induced by neck manipulation in cervical spondylotic myelopathy (CSM): A report of two cases with anatomical and clinical considerations
Authors: Parke Wesley W. , Whalen Joseph L.
Published: August 2002

The clinical records of two male subjects with severe cervical spondylotic myelopathy (CSM) who developed respiratory insufficiency after the cervical manipulation involved in preoperative anesthetic intubation were examined. Their cervical imaging was analyzed with respect to the known anatomic relationships of the spinal phrenic nerve nuclei to the spondylotic compressive lesions in an attempt to provide the anatomic and pathologic rationales that may explain this phrenic paresis as a possible traumatic complication of severe CSM. Perusal of extant literature revealed extensive descriptions of CSM symptoms, but none had previously reported an associated neuromuscular weakness of the diaphragm. Magnetic resonance imaging analyses indicated that the existing degree of upper cervical cord compression, when reinforced by the additional posterior and anterior pressures consequent to cervical spinal extension and flexion, could readily account for the functional impairment of phrenic nerve neuron cells and/or their efferent fibers. Thus, the anatomic relations of the phrenic nerve nuclear columns and their efferent tracts predispose them to interference by compressive lesions found in CSM, and undue manipulation of the cervical spine when advanced stenosis is known to be present should be recognized as a possible cause of cervical spondylotic myelopathic–phrenic paresis. Clin. Anat. 1:173–178, 2001. © 2001 Wiley‐Liss, Inc.
Teaching anatomy with surgeons' tools: Use of the laparoscope in clinical anatomy
Authors: Fitzpatrick Colleen M. , Kolesari Gary L. , Brasel Karen J.
Published: August 2002

The purpose of this study was to establish the feasibility of laparoscopy in embalmed cadavers to teach abdominal gross anatomy. One cadaver was selected based on body habitus and absence of previous abdominal operations. A standard trocar was used to enter the abdomen at the umbilicus. Two trocars were placed in the left upper quadrant. Pneumoperitoneum was achieved with continuous CO2 pressure. Liver retraction was achieved percutaneously, exposing the porta hepatis and the gallbladder. The dissection was done with four first‐year medical students using standard laparoscopic equipment. Following this, the demonstration was projected over multiple monitors so that all students could participate. Laparoscopic dissection in an embalmed cadaver is feasible and an excellent educational tool for both the medical student and the dissector. The dissector has the opportunity to manipulate laparoscopic tools in a human model closely paralleling operative experience, and the students have an opportunity to learn abdominal anatomy from a clinical perspective. Laparoscopic examination and dissection of fresh cadavers has been used for training surgeons on new procedures such as colon resection, antireflux procedures, and cholecystectomy. There is no report of this same technology used in embalmed cadavers to teach basic anatomy. This approach allows first‐year medical students to learn the anatomy while exposing them to the technology currently used in surgical practice, and it affords surgical residents and students additional opportunities to practice laparoscopic skills. Clin. Anat. 5:349–353, 2001. © 2001 Wiley‐Liss, Inc.