bluuebunny/crossref_metadata_2025 huggingface dataset:
Measurement of the individual exposure to 50 and 16 2/3 Hz magnetic fields within the Bavarian population
Authors: Brix J. , Wettemann H. , Scheel O. , Feiner F. , Matthes R.
Published: August 2002

This study investigates the individual magnetic field exposures at 16 2/3 and 50 Hz of 1952 people, selected from the Bavarian population. Personal flux density meters (“Field Watcher FW2A”) were worn by the participants for 24 h. Every second, the flux density was recorded for both frequencies and for the three spatial axes (dynamic range per axis: several nT up to 100 μT at 50 Hz, 150 μT at 16 2/3 Hz). For 50 Hz fields, the mean of the 1,952 individual means was 0.101 μT and that of the individual medians was 0.047 μT. High level exposures occurred mainly during working hours. Only 2.4% of the subjects showed individual medians higher than 0.2 μT. About 53% of all volunteers were working on the day of recording. Levels for craftsmen (n = 148; mean individual mean: 0.166 μT) were generally higher than those for office workers (n = 624; mean individual mean: 0.107 μT). Flux densities exceeding 100 μT at 50 Hz were measured in 31 persons. The total time with such extreme exposures amounts to nearly 21 min, less than 0.001% of the total time for all measurements (5.3 years). To our knowledge, this is the first exposure study where 16 2/3 Hz magnetic fields (caused by electrified railways) have additionally been monitored over 24 h. For persons living next to railway lines, the mean individual mean (0.156 μT) and mean individual median (0.102 μT) were calculated. Over all, the mean exposures are only 0.1% of the magnetic flux density limit for 50 Hz (100 μT) and about 0.05% of the limit (300 μT) for 16 2/3 Hz recommended by the International Commission on Non‐Ionizing Radiation Protection. Bioelectromagnetics 22:323–332, 2001. © 2001 Wiley‐Liss, Inc.
Intracellular effect of ultrashort electrical pulses
Authors: Schoenbach Karl H. , Beebe Stephen J. , Buescher E. Stephen
Published: August 2002

A simple electrical model for biological cells predicts an increasing probability for electric field interactions with cell substructures of prokaryotic and eukaryotic cells when the electric pulse duration is reduced into the sub‐microsecond range. The validity of this hypothesis was verified experimentally by applying electrical pulses with electric field intensities of up to 5.3 MV/m to human eosinophils in vitro. When 3–5 pulses of 60 ns duration were applied to human eosinophils, intracellular granules were modified without permanent disruption of the plasma membrane. In spite of the extreme electrical power levels applied to the cells thermal effects could be neglected because of the ultrashort pulse duration. The intracellular effect extends conventional electroporation to cellular substructures and opens the potential for new applications in apoptosis induction, gene delivery to the nucleus, or altered cell functions, depending on the electrical pulse conditions. Bioelectromagnetics 22:440–448, 2001. © 2001 Wiley‐Liss, Inc.
Histone ubiquitination: a tagging tail unfolds?
Authors: Jason Laure J.M. , Moore Susan C. , Lewis John D. , Lindsey George , Ausió Juan
Published: August 2002

Despite the fact that histone H2A ubiquitination affects about 10–15% of this histone in most eukaryotic cells, histone ubiquitination is among one of the less‐well‐characterized post‐translational histone modifications. Nevertheless, some important observations have been made in recent years. Whilst several enzymes had been known to ubiquitinate histones in vitro, recent studies in yeast have led to the unequivocal identification of the enzyme responsible for this post‐translational modification in this organism. A strong functional co‐relation to meiosis and spermiogenesis has also now been well documented, although its participation in other functional aspects of chromatin metabolism, such as transcription or DNA repair, still remains rather speculative and controversial. Because of its nature, histone ubiquitination represents the most bulky structural change to histones and as such it would be expected to exert an important effect on chromatin structure. Past and recent structural studies, however, indicate a surprising lack of effect of (H2A/H2B) ubiquitination on nucleosome architecture and of uH2A on chromatin folding. These results suggest that this modification may serve as a signal for recognition by functionally relevant trans‐acting factors and/or operate synergistically in conjunction with other post‐translational modifications such as for instance acetylation. BioEssays 24:166–174, 2002. © 2002 Wiley Periodicals, Inc.
A fresh look at the role of CaMKII in hippocampal synaptic plasticity and memory
Authors: Rongo Christopher
Published: August 2002

Advances in molecular, genetic, and cell biological techniques have allowed neuroscientists to delve into the cellular machinery of learning and memory. The calcium and calmodulin‐dependent kinase type II (CaMKII) is one of the best candidates for being a molecular component of the learning and memory machinery in the mammalian brain. It is present in abundance at synapses and its enzymatic properties and responsiveness to intracellular Ca2+ fit a model whereby Ca2+ currents activate the kinase and lead to changes in synaptic efficacy. Indeed, such plastic properties of synapses are thought to be important for memory formation. Genetic analysis of the alpha isoform of CaMKII in mice support the hypothesis that CaMKII signaling is required to initiate the formation of new spatial memories in the hippocampus. CaMKII is also required for the correct induction of long‐term potentiation (LTP) in the hippocampus, consistent with the widely held belief that LTP is a mechanism for learning and memory. Recent cell biological, genetic, and physiological analyses suggest that one of the cellular explanations for LTP and CaMKII function might be the trafficking of AMPA‐type receptors to synapses in response to neural activity. BioEssays 24:223–233, 2002. © 2002 Wiley Periodicals, Inc.; DOI 10.1002/bies.10057
Braking the silence: How heterochromatic gene repression is stopped in its tracks
Authors: Donze David , Kamakaka Rohinton T.
Published: August 2002

Eukaryotic DNA is assembled into nucleosomes, which are further packaged into higher order chromatin structures containing many non‐histone chromosomal proteins. The details of this packaging have profound effects on gene expression and other cellular processes involving the genetic material. Heterochromatic domains of the genome are usually transcriptionally repressed, while euchromatic regions are transcriptionally competent. Current models of gene activation postulate the existence of boundary elements that either prevent inappropriate activation of genes by distal enhancers (enhancer blockers), or sequences that block the propagation of heterochromatin into euchromatic regions (barriers). While numerous boundary sequences have been identified, little is known with regard to the molecular mechanisms used to punctuate the genome. This review will focus on recent data that provide insight into the mode of action of barrier elements. BioEssays 24:344–349, 2002. ©2002 Wiley Periodicals, Inc.
Muscular dystrophies, the cytoskeleton and cell adhesion
Authors: Spence Heather J. , Chen Yun‐Ju , Winder Steven J.
Published: August 2002

Muscular dystrophies are associated with mutations in genes encoding several classes of proteins. These range from extracellular matrix and integral membrane proteins to cytoskeletal proteins, but also include a heterogeneous group of proteins including proteases, nuclear proteins, and signalling molecules. Muscular dystrophy phenotypes have also become evident in studies on various knockout mice defective in proteins not previously considered or known to be mutated in muscular dystrophies. Some unifying themes are beginning to emerge from all of these data. This review will consider recent advances in our understanding of the molecules involved and bring together data that suggest a role for the cytoskeleton and cell adhesion in muscular dystrophies. BioEssays 24:542–552, 2002. © 2002 Wiley Periodicals, Inc.
Checking in on Cds1 (Chk2): A checkpoint kinase and tumor suppressor
Authors: McGowan Clare H.
Published: August 2002

Together, DNA repair and checkpoint responses ensure the integrity of the genome. Coordination of cell cycle checkpoints and DNA repair are especially important following genotoxic radiation or chemotherapy, during which unusually high loads of DNA damage are sustained. In mammalian cells, the checkpoint kinase, Cds1 (also known as Chk2) is activated by ATM in response to DNA damage. The role of Cds1 as a checkpoint kinase depends on its ability to phosphorylate cell cycle regulators such p53, Cdc25 and Brca1. A role for Cds1 in repair is suggested by the finding that it interacts with the Holliday junction resolving activity Mus81. This review focuses on the many questions generated by recent progress in understanding the function and regulation of human Cds1. BioEssays 24:502–511, 2002. © 2002 Wiley Periodicals, Inc.
Wnt signalling: a theme with nuclear variations
Authors: Sharpe Colin , Lawrence Nicola , Arias Alfonso Martinez
Published: August 2002

Wnt proteins are involved in a large number of events during development and disease. The crucial element in the transduction of the signal elicited by Wnt is the state and activity of β‐catenin. There are two pools of β‐catenin, one associated with cadherins at the cell surface and a soluble one in the cytolasm, whose state and concentration are critical for Wnt signalling. In the absence of Wnt, the cytoplasmic pool is low due to targetted degradation of β‐catenin. Upon Wnt signalling, β‐catenin is stabilized. As a consequence, it can access the nucleus where it interacts with members of the Tcf family of transcription factors to modulate the expression of defined targets. Recent reports indicate that, in addition to Tcfs, β‐catenin can interact with other nuclear proteins raising the possibility that Wnt signalling has a wider modulatory effect on transcription than is mediated by its interactions with Tcfs. BioEssays 23:311–318, 2001. © 2001 John Wiley & Sons, Inc.
Therefore, what are recombination proteins there for?
Authors: Courcelle Justin , Ganesan Ann K. , Hanawalt Philip C.
Published: August 2002

The order of discovery can have a profound effect upon the way in which we think about the function of a gene. In E. coli, recA is nearly essential for cell survival in the presence of DNA damage. However, recA was originally identified, as a gene required to obtain recombinant DNA molecules in conjugating bacteria. As a result, it has been frequently assumed that recA promotes the survival of bacteria containing DNA damage by recombination in which DNA strand exchanges occur. We now know that several of the processes that interact with or are controlled by recA, such as excision repair and translesion synthesis, operate to ensure that DNA replication occurs processively without strand exchanges. Yet the view persists in the literature that recA functions primarily to promote recombination during DNA repair. With the benefit of hindsight and more than three decades of additional research, we reexamine some of the classical experiments that established the concept of DNA repair by recombination, and we consider the possibilities that recombination is not an efficient mechanism for rescuing damaged cells, and that recA may be important for maintaining processive replication in a manner that does not generally promote recombination. BioEssays 23:463–470, 2001. © 2001 John Wiley & Sons, Inc.
Master regulatory genes; telling them what to do
Authors: Baker Nicholas E.
Published: August 2002

In 1995, the eyeless (ey) gene was dubbed the “master‐regulator” of eye development in Drosophila. Not only is ey required for eye development, but its misexpression can convert many other tissues into eye, including legs, wings and antennae.(1) ey is remarkable for its ability to drive coordinate differentiation of the multiple cell types that have to differentiate in a very precise pattern to construct the fly eye, and for its power to override the previous differentiation programs of many other diverse tissues. Even more remarkable, the ey homolog Pax6 and homologs of other eye determination genes from Drosophila are also required for eye development in vertebrates,(2,3) prompting reassessment of the evolution of vision throughout the animal kingdom.(4,5) Now Kumar and Moses have published a study that throws a new light on ey function in Drosophila.(6) According to their work, ey becomes a master regulator of eye development much later than previously thought, and is regulated by signalling through the Notch and EGFR signaling pathways. BioEssays 23:763–766, 2001. © 2001 John Wiley & Sons, Inc.
Extended analysis and treatment of self‐injurious behavior
Authors: Healey John J. , Ahearn William H. , Graff Richard B. , Libby Myrna E.
Published: August 2002

In experiment 1, an extended functional analysis of self‐injury was conducted with a 21‐year‐old male diagnosed with autism and profound mental retardation. The multielement phase yielded undifferentiated results. Subsequent blocking of conditions plus the addition of a component allowing access to multiple sensory stimuli suggested that self‐injury was unrelated to programmed positive or negative reinforcement contingencies. The behavior appeared to be automatically reinforced; its occurrence decreased when access to alternative sensory stimuli was provided. Experiment 2 evaluated a treatment condition in which response‐independent access to these sensory stimuli was provided within the participant's everyday environment. Baseline and treatment frequencies of self‐injury were compared in a combined, multiple‐baseline‐across‐settings and ABAB design. The level of self‐injury decreased substantially during treatment. These results support the use of extended analog analyses of aberrant behavior in instances in which undifferentiated responding occurs in the initial analogue analysis. Additionally, a procedure is described for generalizing the intervention derived from the experimental analysis into the participant's everyday environment. Copyright © 2001 John Wiley & Sons, Ltd.
Behavioral treatments for sleep problems in autism: empirically supported or just universally accepted?
Authors: Schreck Kimberly A.
Published: August 2002

With health maintenance organizations and insurance companies requiring proof of treatment efficacy, clinicians must determine whether research supports commonly used treatment methods. To determine the effectiveness of applied behavior analysis (ABA) for treating sleep problems in children with autism, a computer search of all relevant literature was conducted. The resulting articles revealed four basic themes of behavioral techniques for treating sleep disorders for children with autism: bedtime routines, extinction, stimulus fading, and faded bedtimes. Research on each technique was evaluated based on the Chambless criteria of treatment efficacy (Chambless and Hollon, 1998; Lonigan, Elbert, and Johnson, 1998). Of the ABA methods, only research on extinction provided sufficient evidence for a possibly efficacious intervention for sleep problems in children with autism. However, the lack of available research indicates significantly more research must be conducted before endorsing other ABA methods. Copyright © 2001 John Wiley & Sons, Ltd.
Molecular dynamics simulations of α2 → 8‐linked disialoside: Conformational analysis and implications for binding to proteins
Authors: Vasudevan Sheeja V. , Balaji Petety V.
Published: August 2002

Computational methods have played a key role in elucidating the various three‐dimensional structures of oligosaccharides. Such structural information, together with other experimental data, leads to a better understanding of the role of oligosaccharide in various biological processes. The disialoside Neu5Ac‐α2→8‐Neu5Ac appears as the terminal glycan in glycoproteins and glycolipids, and is known to play an important role in various events of cellular communication. Neurotoxins such as botulinum and tetanus require Neu5Ac‐α2 → 8‐Neu5Ac for infecting the host. Glycoconjugates containing this disialoside and the enzymes catalyzing their biosynthesis are also regulated during cell growth, development, and differentiation. Unlike other biologically relevant disaccharides that have only two linkage bonds, the α2→8‐linked disialoside has four: C2—O, O—C8′, C8′—C7′, and C7′—C6′. The present report describes the results from nine 1 ns MD simulations of α2→8‐linked disialoside (Neu5Ac‐α2→8‐Neu5Ac); simulations were run using GROMOS96 by explicitly considering the solvent molecules. Conformations around the O—C8′ bond are restricted to the +sc/+ap regions due to stereochemical reasons. In contrast, conformations around the C2—O and C8′—C7′ bonds were found to be largely unrestricted and all the three staggered regions are accessible. The conformations around the C7′—C6′ bond were found to be in either the −sc or the anti region. These results are in excellent agreement with the available NMR and potential energy calculation studies. Overall, the disaccharide is flexible and adopts mainly two ensembles of conformations differing in the conformation around the C7′—C6′ bond. The flexibility associated with this disaccharide allows for better optimization of intermolecular contacts while binding to proteins and this may partially compensate for the loss of conformational entropy that may be incurred due to disaccharide′s flexibility. © 2002 John Wiley & Sons, Inc. Biopolymers 63: 168–180, 2002; DOI 10.1002/bip.10019
Chemotaxonomy of mints of genus Mentha by applying Raman spectroscopy
Authors: Rösch P. , Kiefer W. , Popp J.
Published: August 2002

The characterization of mints is often problematic because Mentha is a taxonomically complex genus. In order to provide a fast and easy characterization method, we use a combination of micro‐Raman spectroscopy and hierarchical cluster analysis. A classification trial of different mint taxa is possible for one collection time. For spectra measured at different points during the growing season, a more sophisticated pretreatment of the data is necessary to receive good discrimination between the species, as well as between the subspecies and varieties of the mints. © 2002 Wiley Periodicals, Inc. Biopolymers (Biospectroscopy) 67: 358–361, 2002
DNA persistence length revisited
Authors: Lu Yongjun , Weers Brock , Stellwagen Nancy C.
Published: August 2002

DNA restriction fragments ranging from 79 to 789 base pairs in length have been characterized by transient electric birefringence (TEB) measurements at various temperatures between 4 and 43°C. The DNA fragments do not contain runs of four or more adenine residues in a row and migrate with normal electrophoretic mobilities in polyacrylamide gels, indicating that they are not intrinsically curved or bent. The low ionic strength buffers used for the measurements contained 1 mM Tris Cl, pH 8.0, EDTA, and variable concentrations of Na+ or Mg2+ ions. The rotational relaxation times were obtained by fitting the TEB field‐free decay signals with a nonlinear least‐squared fitting program; the decay of the birefringence was monoexponential for fragments ≤ 241 base pair (bp) in length and multiexponential for larger fragments. The terminal relaxation times, characteristic of the end‐over‐end rotation of the DNA molecules, were then used todetermine the persistence length (p) and hydrodynamic radius (r) of DNA as a function of temperature and ionic strength, using several different hydrodynamic models. The specific values obtained for p and r are model dependent. The wormlike chain model of P. J. Hagerman and B. H. Zimm (Biopolymers 1981, Vol. 20, pp. 1481–1502) combined with the revised Broersma equation (J. Newman et al., Journal of Mol Biol 1997, Vol. 116, pp. 593–606) appears to be the most suitable for describing the flexibility of DNA in low ionic strength solutions. The values of p and r obtained from the global least squares fitting of this equation are independent of DNA length, and the deviations of the individual values from the average are reasonably small. The consensus r value calculated for DNA in various low ionic strength solutions containing 1 mM Tris buffer is 14.7 ± 0.4 Å at 20°C. The consensus p values decrease from 814 ∼ 564 Å in solutions containing 1 mM Tris buffer plus 0.2–1 mM NaCl and decrease still further to 440 Å in solutions containing 0.2 mM Mg2+ ions. The persistence length exhibits a shallow maximum at 20°C and decreases slowly upon either increasing or decreasing the temperature, regardless of the model used to fit the data. By contrast, the consensus values of the hydrodynamic radius are independent of temperature. The calculated persistence lengths and hydrodynamic radii are compared with other data in the literature. © 2002 Wiley Periodicals, Inc. Biopolymers 61: 261–275, 2002
Using ATP bioluminescence technique for monitoring microbial activity in sludge
Authors: Chu C. P. , Lee D. J. , Chang Bea‐Ven , Liao C. S.
Published: August 2002

This study demonstrates, for the first time, that the presence of suspended solids in waste‐activated sludge interferes with adenosine triphosphate (ATP) bioluminescence tests. The sludge subject to acid/alkaline treatment represented the test sample. Without consideration of the effect of solid concentrations, one would erroneously estimate the density levels of heterotrophic bacteria in the sludge using ATP data. A light blockage model was proposed to evaluate the luminescence reading without the interference of suspended solids. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 75: 469–474, 2001.
Optimal temperature policy for immobilized enzyme packed bed reactor performing reversible Michaelis–Menten kinetics using the disjoint policy
Authors: Faqir Naim M. , Attarakih Menwer M.
Published: August 2002

The optimal temperature policy that maximizes the time‐averaged productivity of a continuous immobilized enzyme packed bed reactor is determined. This optimization study takes into consideration the enzyme thermal deactivation with substrate protection during the reactor operation. The general case of reversible Michaelis–Menten kinetics under constant reactor feed flow rate is assumed. The corresponding nonlinear optimization problem is solved using the calculus of variations by applying the disjoint policy. This policy reduces the optimization problem into a differential‐algebraic system, DAE. This DAE system defines completely the optimal temperature–time profiles. These profiles depend on the kinetic parameters, feed substrate concentration, operating period, and the residence time and are characterized by increasing form with time. Also, general analytical expressions for the slopes of the temperature and residual enzyme activity profiles are derived. An efficient solution algorithm is developed to solve the DAE system, which results into a one‐dimensional optimization problem with simple bounds on the initial feed temperature. The enzymatic isomerization of glucose into fructose is selected as a case study. The computed productivities are very close to that obtained by numerical nonlinear optimization with simpler problem to solve. Moreover, the computed conversion profiles are almost constant over 90% of the operating periods, thus producing a homogeneous product. © 2002 John Wiley & Sons, Inc. Biotechnol Bioeng 77: 163–173, 2002.
A microfabricated array bioreactor for perfused 3D liver culture
Authors: Powers Mark J. , Domansky Karel , Kaazempur‐Mofrad Mohammad R. , Kalezi Artemis , Capitano Adam , Upadhyaya Arpita , Kurzawski Petra , Wack Kathryn E. , Stolz Donna Beer , Kamm Roger , Griffith Linda G.
Published: August 2002

We describe the design, fabrication, and performance of a bioreactor that enables both morphogenesis of 3D tissue structures under continuous perfusion and repeated in situ observation by light microscopy. Three‐dimensional scaffolds were created by deep reactive ion etching of silicon wafers to create an array of channels (through‐holes) with cell‐adhesive walls. Scaffolds were combined with a cell‐retaining filter and support in a reactor housing designed to deliver a continuous perfusate across the top of the array and through the 3D tissue mass in each channel. Reactor dimensions were constructed so that perfusate flow rates meet estimated values of cellular oxygen demands while providing fluid shear stress at or below a physiological range (<2 dyne cm2), as determined by comparison of numerical models of reactor fluid flow patterns to literature values of physiological shear stresses. We studied the behavior of primary rat hepatocytes seeded into the reactors and cultured for up to 2 weeks, and found that cells seeded into the channels rearranged extensively to form tissue like structures and remained viable throughout the culture period. We further observed that preaggregation of the cells into spheroidal structures prior to seeding improved the morphogenesis of tissue structure and maintenance of viability. We also demonstrate repeated in situ imaging of tissue structure and function using two‐photon microscopy. © 2002 Wiley Periodicals, Inc. Biotechnol Bioeng 78: 257–269, 2002.
Control of the redox potential by oxygen limitation improves bacterial leaching of chalcopyrite
Authors: Third K. A. , Cord‐Ruwisch R. , Watling H. R.
Published: August 2002

Shake flask and stirred tank bioleaching experiments showed that the dissolution of chalcopyrite is inhibited by ferric ion concentrations as low as 200 mg L−1 and redox potentials >420 mV (vs. Ag/AgCl). Chemical leaching of chalcopyrite (4% suspension, surface area 2.3 m2 g−1) was enhanced fourfold in the presence of 0.1 M ferrous sulphate compared with 0.1 M ferric sulphate. A computer‐controlled reactor was designed to function as a “potentiostat”‐bioreactor by arresting the air supply to the reactor when the redox potential in solution was greater than a designated setpoint. Leaching at a low, constant redox potential (380 mV vs. Ag/AgCl) achieved final copper recoveries of 52%–61%, which was twice that achieved with a continuous supply of oxygen (<30% extraction). The bacterial populations were observed to continue growing under oxygen limitation but in a controlled manner that was found to improve chalcopyrite dissolution. As the control mechanism is easily established and is likely to decrease production cost, the use of this technology may find application in industry. © 2002 Wiley Periodicals, Inc. Biotechnol Bioeng 78: 433–441, 2002.
Optimizing the heterologous production of epothilone D in Myxococcus xanthus
Authors: Lau Janice , Frykman Scott , Regentin Rika , Ou Sally , Tsuruta Hiroko , Licari Peter
Published: August 2002

The heterologous production of epothilone D in Myxococcus xanthus was improved by 140‐fold from an initial titer of 0.16 mg/L with the incorporation of an adsorber resin, the identification of a suitable carbon source, and the implementation of a fed‐batch process. To reduce the degradation of epothilone D in the basal medium, XAD‐16 (20 g/L) was added to stabilize the secreted product. This greatly facilitated its recovery and enhanced the yield by three‐fold. The potential of using oils as a carbon source for cell growth and product formation was also evaluated. From a screen of various oils, methyl oleate was shown to have the greatest impact. At the optimal concentration of 7 mL/L in a batch process, the maximum cell density was increased from 0.4 g dry cell weight (DCW)/L to 2 g DCW/L. Product yield, however, depended on the presence of trace elements in the production medium. With an exogenous supplement of trace metals to the basal medium, the peak epothilone D titer was enhanced eight‐fold. This finding demonstrates the significant role of metal ions in cell metabolism and in epothilone biosynthesis. To further increase the product yield, a continuous fed‐batch process was used to promote a higher cell density and to maintain an extended production period. The optimized fed‐batch cultures consistently yielded a cell density of 7 g DCW/L and an average production titer of 23 mg/L. © 2002 Wiley Periodicals, Inc. Biotechnol Bioeng 78: 280–288, 2002.
Variations in the enantioselectivity of salt‐activated subtilisin induced by lyophilization
Authors: Hsu Wei‐Ting , Clark Douglas S.
Published: August 2002

Including excess salt during lyophilization has been shown to increase the activity of freeze‐dried subtilisin Carlsberg (SC) in anhydrous media by over 20,000‐fold [Ru et al. (1999) Biotechnol Bioeng 63:233–241]. In the present study, salt‐activated SC (KCl‐SC) showed a 30% enhancement in enantioselectivity compared to the salt‐free enzyme in a variety of organic solvents. Activity toward both enantiomers of N‐acetyl‐phenylalanine methyl ester (APME) increased in tandem by 2–3 orders of magnitude in all solvents, indicating that the mechanism of salt activation is inherent to the enzyme and does not strongly favor one enantiomer over the other. However, activity and enantioselectivity of salt‐activated SC could be manipulated through changes in the lyophilization conditions. Variations in lyophilization time, initial KCl concentration, and initial lyophilization volume altered enantioselectivity over 2‐fold. The changes in enantioselectivity reflected the activity for the L enantiomer, while the activity toward the D enantiomer was mostly unaffected. The results indicate that the lyophilization time and final water content of the KCl‐SC are important determinants of enzyme activity for the L enantiomer, suggesting that the favored reaction is more sensitive to the structural integrity of the salt‐activated enzyme. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 73: 231–237, 2001.
Characterization of monoclonal antibody fragments produced by plant cells
Authors: Sharp Janet M. , Doran Pauline M.
Published: August 2002

Production of a murine IgG1 was investigated using hairy roots, shooty teratomas, and suspended cells of transgenic tobacco. In all cases, in addition to complete assembled antibody, two to four major antibody fragments accumulated in the biomass. A range of protease inhibitors, protein‐stabilizing agents, inhibitors of N‐glycosylation and protein secretion, glycan‐reactive agents, and affinity probes was used to characterize these fragments and investigate their sites and mechanisms of formation. The fragments were not experimental artifacts caused by antibody degradation during tissue homogenization and sample preparation, nor did they represent glycosylation variants. All of the molecules were actively secreted into the culture media and some showed evidence of Golgi‐associated glycan processing, indicating they were not assembly intermediates. Antibody fragments of 50 and 80 kDa were identified mainly as the products of extracellular degradation in the root and shoot apoplast; the 80‐kDa fragment was also present in cell suspension medium, and in suspended cell biomass toward the end of the growth phase. Larger 120‐ and 135‐kDa fragments were most likely produced by proteolytic degradation along the secretory pathway outside of the endoplasmic reticulum (ER) and Golgi apparatus; the carbohydrate residues of the 135‐kDa antibody suggest formation between these organelles. Inhibition of protein secretion and retention of antibody in the ER and/or Golgi reduced fragmentation and increased antibody accumulation levels, probably by reducing exposure to the principal sites of protease activity. This work highlights the importance of foreign protein degradation in plant tissues as a mechanism for posttranslational product loss. Identifying the nature of these degradative processes is a first step toward alleviating their effects, improving protein yields, and enhancing the feasibility of plants as a commercial means for large‐scale protein production. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 73: 338–346, 2001.
Integrated flow‐injection processing for on‐line quantification of plasmid DNA during cultivation of E. coli
Authors: Nandakumar M. P. , Karlsson E. Nordberg , Mattiasson B.
Published: August 2002

An integrated flow‐injection processing (FIP) system for the quantification of plasmids during cultivation is described. The system performs on‐line sampling, cell lysis, and quantification of plasmids in an integrated manner during cultivation of E. coli. The system was operated by using a miniaturized expanded‐bed column which can be used for handling samples containing cells and cell debris without interfering with the binding analysis. Two types of detectors (one measuring UV absorbance at 254 nm and a fluorometer) are used for on‐line plasmid detection. The system was developed using standard solutions and it was successfully applied in monitoring plasmid contents during a cultivation of E. coli. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 73: 406–411, 2001.
On‐line determination of animal cell concentration in two industrial high‐density culture processes by dielectric spectroscopy
Authors: Ducommun P. , Kadouri A. , von Stockar U. , Marison I. W.
Published: August 2002

Dielectric spectroscopy was applied to two industrial high cell density culture processes and used to determine on‐line the concentration of CHO cells immobilized on macroporous microcarriers in a stirred bioreactor and in a packed‐bed of disk carriers. The cell concentration predicted from the spectroscopic data was in excellent agreement with off‐line cell counting data for both processes. Deviations between the two counting methods only occurred in the case of a significant decrease of the cell viability, from 93% to 64%, which induced a change of the average cell size in the culture. Results for the packed‐bed process were further confirmed by the application of indirect yield models based on the measurement of glucose, lactate, and the protein of interest. Moreover, dielectric spectroscopy was used as a tool to characterize the packed‐bed process. It was possible to determine both the maximum cell concentration that could be reached in the culture system, 2.0 × 1011 cell per kg of disk carrier, and to quantify the increase of specific protein productivity induced by the production phase, from 5.14 × 10−8 μg cell−1 h−1 to 4.24 × 10−7 μg cell−1 h−1. © 2002 John Wiley & Sons, Inc. Biotechnol Bioeng 77: 316–323, 2002.
Determination of bisphenol A and 10 alkylphenols in serum using SDS micelle capillary electrophoresis with γ‐cyclodextrin
Authors: Katayama Masatoki , Matsuda Yoshifumi , Sasaki Tadahiro , Shimokawa Ken‐ichi , Kaneko Satoru , Iwamoto Teruaki
Published: August 2002

A new micelle capillary electrophoresis based on cyclodextrin micellar electrokinetic chromatography (MEKC) for the determination of bisphenol A and 10 alkylphenols in rat serum is reported. Several surfactants and dextrins were studied. Bisphenol A and alkylphenols were separated using a 50 µm × 50 cm capillary with 20 mM borate phosphate buffer (pH 8.0) containing 20 mM sodium dodecylsulfate and 5 mM γ‐cyclodextrin as carrier. The method could determine 0.6–2000 µg/mL of phenols in 100 µL serum by photometric detection at 214 nm. Using 2.0 mL serum, 1.0 ng/mL of phenols could be determined. The relative standards deviations were 6.3–7.7% at 10 µg/mL in serum. The recoveries were 91.8–93.0% with 10 µg/mL serum samples. Copyright © 2001 John Wiley & Sons, Ltd.
Government and NGO partnership in managing community‐based water resources in Vietnam: a case study of Thai Long Dam Project
Authors: Sinh Bach Tan
Published: August 2002

Economic reform policy called ‘Doi Moi’ introduced by the Government of Vietnam at the end of 1980s opened new opportunities of community‐based involvement in the policy and decision‐making at various local levels. Innovations such as decentralization of decision‐making power to lower administrative level, and recognition of the local community's role in managing their natural resources, e.g. transfer of irrigated water management right to local communities, were introduced.

Significantly, this new institutional framework also facilitated greater civil society involvement in Vietnam. The Water Users Cooperative (WUC) set up through the Thai Long Dam Project mobilized local farmers to participate and manage their local resources in a sustainable manner. Through this process, the WUC was able to strengthen itself as a civil society institution that mediates between the individual and the state, as well as a forum for increasing government responsiveness and accountability.

The success of the WUC of the Thai Long Project implies that the Vietnamese civil society is playing a more active role in the decision‐making process. Copyright © 2002 John Wiley & Sons, Ltd. and ERP Environment
Who's in, who's out, and who's back: follow‐up data on 59 juveniles incarcerated in adult prison for murder or attempted murder in the early 1980s
Authors: Heide Kathleen M. , Spencer Erin , Thompson Andrea , Solomon Eldra P.
Published: August 2002

Since the mid‐1980s, when juvenile arrests for violent crime increased dramatically, interest has focused on juvenile offenders who commit violent acts. Legislatures across the United States have enacted a variety of measures to “get tough” with juveniles in response to escalating crime rates and the perceptions that longer sentences were needed. This manuscript provides follow‐up data on 59 juveniles who were committed to the adult Department of Corrections in Florida during the period January 1982 through January 1984 for one or more counts of murder, attempted murder, or, in a few cases, manslaughter. Although many of these adolescents received lengthy prison sentences, more than two‐thirds had been released from prison prior to November 1999. This article presents data on amount of time served and recidivism over the 15 to 17 year period. Results indicated that 60 percent of sample subjects released from prison were returned to prison, and most of those who failed did so within the first three years of release. Findings from the present study, when examined in the context of previous comparative follow‐up studies of delinquent youths, suggest that the dialogue on how to handle violent youths must be continued if juvenile homicide offenders are going to be released to society at some point in the future. Copyright © 2001 John Wiley & Sons, Ltd.
Mixed group validation: a method to address the limitations of criterion group validation in research on malingering detection*
Authors: Frederick Richard I.
Published: August 2002

Mixed group validation (MGV) is offered as an alternative to criterion group validation (CGV) to estimate the true positive and false positive rates of tests and other diagnostic signs. CGV requires perfect confidence about each research participant's status with respect to the presence or absence of pathology. MGV determines diagnostic efficiencies based on group data; knowing an individual's status with respect to pathology is not required. MGV can use relatively weak indicators to validate better diagnostic signs, whereas CGV requires perfect diagnostic signs to avoid error in computing true positive and false positive rates. The process of MGV is explained, and a computer simulation demonstrates the soundness of the procedure. MGV of the Rey 15‐Item Memory Test (Rey, 1958) for 723 pre‐trial criminal defendants resulted in higher estimates of true positive rates and lower estimates of false positive rates as compared with prior research conducted with CGV. The author demonstrates how MGV addresses all the criticisms Rogers (1997b) outlined for differential prevalence designs in malingering detection research. Copyright © 2000 John Wiley & Sons, Ltd.
Upper dental prosthesis instability consecutive to the resection of a cerebral tumor
Authors: Pérusse Rénald , LaFlèche Roland , Tremblay Steve
Published: August 2002

A 57‐year‐old female patient was evaluated for an unstable maxillary dental prosthesis. The patient stated that approximately 2 weeks prior to this consultation the prosthesis was relined four times. Despite this, it often had a tendency to shift during meals. On the other hand, she is very satisfied with a complete fixed prosthesis on implants in the mandibular arch. She has been wearing this latter lower prosthesis for the same length of time as the upper prosthesis. She indicated that a similar problem existed with the former upper prosthesis, resulting in her consulting a prosthodontist. Clin. Anat. 14:269–271, 2001. © 2001 Wiley‐Liss, Inc.
Sternomastoid paradox
Authors: Fitzgerald Turlough
Published: August 2002

In the standard routine for testing cranial nerve function following a cerebrovascular accident (CVA) compromising the corticonuclear supply to the cranial nerves, sternomastoid muscle (SCM) function is checked by means of head rotation against resistance. SCM appears to be an exception to the generally contralateral motor weakness resulting from a CVA. The thrust of this article is that appearances can be deceptive: SCM is more likely to be a postural stabilizer than a prime mover in head rotation. Clin. Anat. 14:330–331, 2001. © 2001 Wiley‐Liss, Inc.
Developing an intelligent system for teaching pre‐tender cost estimating of office building projects
Authors: Shen Qiping , Fong Patrick S. W. , Deng Michael Z. M.
Published: August 2002

Pre‐tender cost estimating of office building projects requires extensive knowledge and expertise. Due to the lack of design information in the early design stages, it is extremely difficult for cost engineers or quantity surveyors to arrive at an accurate cost estimate. This paper presents the design and testing of a knowledge‐based system that enables students to learn cost estimating of building projects in the conceptual design stages. The system, embedded with knowledge from experts, has been proved to be a very useful teaching and learning tool. © 2001 John Wiley & Sons, Inc. Comput Appl Eng Educ 9: 26–36, 2001
Mental disease postpartum and parent‐infant interaction—evaluation of videotaped sessions
Authors: Albertsson‐Karlgren Ulla , Graff Magdalena , Nettelbladt Per
Published: August 2002

In order to investigate the influence of maternal mental illness postpartum on mother‐infant and father‐infant interaction, infants of 14 mentally ill women admitted to hospital within 6 months after delivery were compared to infants of 22 women who had been somatically ill. Videotaped sessions when the infant was 10 months old revealed that mothers in the psychiatric sample showed less sensitivity in comparison to mothers in the somatic sample. When the infant was 2 years old, mothers in the psychiatric sample showed less positive affect and less link‐infant follow (stimulation dimension) as compared to the somatic mothers. However, there were no differences between fathers in the psychiatric sample and fathers in the somatic sample in any of the interaction variables. In the psychiatric sample, fathers showed more warmth as compared to mothers. In the somatic sample, fathers scored higher than mothers on autonomy but lower than mothers on link‐infant follow (stimulation dimension). A possible interpretation of our data was that the mental illness of the mothers may lead to a more active parenting role of the father in order to buffer the deficit in the mother‐infant relation. Copyright © 2001 John Wiley & Sons, Ltd.
Peer victimization and self‐esteem of ethnic minority group children
Authors: Verkuyten Maykel , Thijs Jochem
Published: August 2002

An experimental study was carried out among Turkish children (10 to 12 years) living in the Netherlands for examining the relationship between peer victimization and self‐esteem. Related to the social psychological distinction between personal and social identity, a distinction was made between personal and ethnic self‐esteem and between personal and ethnic victimization. It was found that personal self‐esteem negatively predicted personal victimization but not ethnic victimization, and ethnic self‐esteem tended to predict ethnic victimization but not personal victimization. Furthermore, peer victimization had a negative causal effect on momentary self‐feelings independent of the level of self‐esteem. In addition, peer victimization based on ethnic group membership had a somewhat stronger negative effect on self‐feelings than victimization based on personal characteristics. Copyright © 2001 John Wiley & Sons, Ltd.
Making the transition to the senior institution
Authors: Eggleston Latrice E. , Laanan Frankie Santos
Published: August 2002

This chapter reviews the current literature on support programs tailored to assist the community college transfer student at the four‐year institution. The authors discuss useful strategies that may assist administrators and faculty members at four‐year colleges and universities in addressing the needs of transfer students through support programs. Support programs, academic performance, and the persistence of transfer students are discussed.
Blurring the lines: Transforming terminal education to transfer education
Authors: Townsend Barbara K.
Published: August 2002

The distinction between transfer and terminal education increasingly blurs as community college students once viewed as terminal begin to dominate the traditional transfer mission of the community college.
Incomplete retention after direct myocardial injection
Authors: Grossman P. Michael , Han Zhenguo , Palasis Maria , Barry James J. , Lederman Robert J.
Published: August 2002

Direct intramyocardial injection may permit local delivery of protein and gene therapy agents for myocardial and coronary artery disease. Little is known about the immediate fate of materials administered via percutaneous endomyocardial catheters or via surgical epicardial injection. In this study, we use a novel method to evaluate the acute retention of agents injected directly into the myocardium, compare epicardial with the percutaneous endocardial and postmortem delivery, and evaluate the influence of injectate volume on myocardial retention. Fifteen 40–50 kg pigs underwent overlapping myocardial injections using a percutaneous endomyocardial catheter, an epicardial needle via an open chest, and epicardial needle postmortem. Multiple distinct 15 μ neutron‐activated microsphere species were used as tracers. Two or three myocardial walls were injected in each animal using 3.5 mm, 27–28 gauge needles at varying injectate volumes. Animals were sacrificed immediately. Myocardial walls were divided and multiple microsphere species were quantified. In an additional study, nine 70 kg pigs underwent percutaneous endomyocardial injections with replication‐deficient adenovirus encoding for the production of lac‐Z. The injectate volume was varied, while the viral particle number remained constant. The animals were sacrificed 5 days after the percutaneous injections; the heart, liver, and spleen were collected for β‐galactosidase activity. Endomyocardial injection was associated with 43% ± 15% microsphere retention, compared with 15% ± 21% (P < 0.01) retention of open chest epicardial injection and 89% ± 60% (P < 0.01) for postmortem injection. Reducing the injectate volume from 100 to 10 μL improved microsphere retention (P = 0.01). There was a trend toward improved viral transfection associated with smaller injection volumes. Despite direct intramyocardial administration, a significant fraction of injectate is not retained locally. Catheter‐based needle endomyocardial injection is associated with equivalent or superior injectate retention compared with open chest epicardial injection. Proportionately, more injectate may be retained at lower volumes. Loss may involve a combination of channel leakage, venous, and lymphatic return. Cathet Cardiovasc Intervent 2002;55:392–397. © 2002 Wiley‐Liss, Inc.