bluuebunny/crossref_metadata_2025 huggingface dataset:
Cloning of a muscle-specific calpain from the American lobsterHomarus americanus: expression associated with muscle atrophy and restoration during moulting
Authors: Yu Xiaoli , Mykles Donald L.
Published: January 2003

A cDNA (1977 bp) encoding a crustacean calpain (Ha-CalpM; GenBank accession no. AY124009) was isolated from a lobster fast muscle cDNA library. The open reading frame specified a 575-amino acid (aa) polypeptide with an estimated mass of 66.3 kDa. Ha-CalpM shared high identity with other calpains in the cysteine proteinase domain (domain II; aa 111-396) and domain III (aa 397-575), but most of the N-terminal domain (domain I; aa 1-110) was highly divergent. Domain II contained the cysteine, histidine and asparagine triad essential for catalysis, as well as two conserved aspartate residues that bind Ca2+. In domain III an acidic loop in the C2-like region, which mediates Ca2+-dependent phospholipid binding, had an expanded stretch of 17 aspartate residues. Ha-CalpM was classified as a non-EF-hand calpain, as it lacked domain IV, a calmodulin-like region containing five EF-hand motifs. Northern blot analysis, relative reverse transcription-polymerase chain reaction (RT-PCR) and real-time PCR showed that Ha-CalpM was highly expressed in skeletal muscles, but at much lower levels in heart, digestive gland, intestine, integument, gill, nerve cord/thoracic ganglion and antennal gland. An antibody raised against a unique N-terminal sequence recognized a 62 kDa isoform in cutter claw and crusher claw closer muscles and a 68 kDa isoform in deep abdominal muscle. Ha-CalpM was distributed throughout the cytoplasm, as well as in some nuclei, of muscle fibers. Purification of Ha-CalpM showed that the 62 kDa and 68 kDa isoforms co-eluted from gel filtration and ion exchange columns at positions consistent with those of previously described Ca2+-dependent proteinase III(CDP III; 59 kDa). Ha-CalpM mRNA and protein did not change during the moulting cycle. The muscle-specific expression of Ha-CalpM and the ability of Ha-CalpM/CDP III to degrade myofibrillar proteins suggest that it is involved in restructuring and/or maintaining contractile structures in crustacean skeletal muscle.
Condition, prolonged swimming performance and muscle metabolic capacities of codGadus morhua
Authors: Martínez M. , Guderley H. , Dutil J.-D. , Winger P. D. , He P. , Walsh S. J.
Published: January 2003

This study evaluated the link between swimming endurance and condition of Atlantic cod Gadus morhua that had been fed or starved during the 16 weeks preceding the tests, and assessed whether muscle metabolic capacities explain such links. The condition factor [(somatic mass × fork length-3)×100] of starved cod was 0.54±0.1 whereas that of fed cod was 0.81±0.1. In white and red muscle, we measured four glycolytic enzymes: phosphofructokinase (PFK), pyruvate kinase (PK), creatine kinase (CK) and lactate dehydrogenase (LDH), two mitochondrial enzymes:cytochrome c oxidase (CCO) and citrate synthase (CS), a biosynthetic enzyme, nucleoside diphosphate kinase (NDPK), glycogen and protein levels and water content. Muscle samples were taken at three positions along the length of the fish; starvation affected the metabolic capacities of white muscle more than those of red muscle. The levels of glycolytic enzymes and glycogen changed more in white than red muscle during starvation. Both in fed and starved cod, muscle metabolic capacities varied with position along the fish;starvation reduced this longitudinal variation more in white than red muscle. In white muscle of fed cod, the glycolytic enzyme levels increased from head to tail, while in starved cod this longitudinal variation disappeared. In red muscle mitochondrial enzyme levels were highest in the caudal sample, but fewer differences were found for glycolytic enzymes. Swimming endurance was markedly affected by fish condition, with starved fish swimming only 30% of the time (and distance) of fed fish. This endurance was closely linked with the number of burst—coast movements during the test and the activity of CCO and LDH in white muscle. The number of burst—coast movements was significantly linked with condition factor and PFK activity in caudal red muscle and gill arch mass. Our data indicated that cod use both glycolytic and oxidative capacities to support endurance swimming. Furthermore, swimming endurance is linked with the metabolic capacities of red and white muscle.
On-line venous oxygen tensions in rainbow trout during graded exercise at two acclimation temperatures
Authors: Farrell A. P. , Clutterham S. M.
Published: January 2003

For most teleost fish, the majority of the myocardial oxygen supply is provided by the oxygen reserve remaining in venous blood after other tissues have extracted oxygen. We examined the effect of graded exercise and water temperature on this venous blood oxygen supply to the heart (termed the cardiac circulation) by performing novel on-line measurements of venous partial pressure of oxygen (PvO2) using a fibreoptic micro-optode implanted in the ductus Cuvier of rainbow trout(Oncorhynchus mykiss). As expected, PvO2 decreased progressively and significantly as swimming velocity approached the critical swimming speed(Ucrit). Unsteady swimming behaviours during the graded exercise, however, caused abrupt and generally short-lived decreases in PvO2. For the cold-acclimated (6-10°C)fish, PvO2 reached a minimum plateau value of 15.3±3.7 torr (1 torr=133.3 Pa) before Ucrit was reached, and so increased swimming effort near to Ucritdid not reduce PvO2 further. Warm-acclimated fish had a significantly higher PvO2(28.9±3.5 torr) at Ucrit. Despite this difference in the PvO2 at Ucrit, we estimated that there was little difference between warm- and cold-acclimated fish in terms of oxygen supply in the cardiac circulation because of a right-shift in the haemoglobin—oxygen dissociation curve at warm temperatures. Furthermore, although PvO2decreased significantly at Ucrit, our estimates suggest that the expected increase in cardiac output would easily maintain the oxygen supply in venous blood at a level similar to that found in resting fish. Although unsteady swimming behaviours decreased PvO2, unsteady swimming rarely decreased the minimum PvO2 value observed at Ucrit by more than 10%. The findings are discussed in terms of a threshold PvO2 required to maintain adequate rates of oxygen diffusion from the cardiac circulation to the myocardial tissues.
Magnet-induced disorientation in hatchling loggerhead sea turtles
Authors: Irwin William P. , Lohmann Kenneth J.
Published: January 2003

Laboratory experiments have indicated that hatchling loggerhead sea turtles(Caretta caretta) are able to establish and maintain courses using information from the Earth's magnetic field. In previous experiments, turtles were tested in relatively uniform magnetic fields generated by large coil systems surrounding an orientation arena. In this study, we investigated the orientation behavior of hatchlings with either magnets or magnetically inert brass bars attached to their carapaces. Control turtles (with brass bars)oriented significantly towards the east whereas turtles bearing magnets were not significantly oriented as a group. The two distributions were statistically different. These results indicate that magnetic orientation behavior of hatchling sea turtles can be disrupted by attaching a small magnet to the carapace. This finding may prove useful both in field experiments and in efforts to localize magnetoreceptors.
Dietary sodium inhibits aqueous copper uptake in rainbow trout(Oncorhynchus mykiss)
Authors: Pyle G. G. , Kamunde C. N. , McDonald D. G. , Wood C. M.
Published: January 2003

Ours is the first study to demonstrate an influence of dietary sodium on waterborne copper uptake in fish. We examined possible interactions between dietary sodium and the response of freshwater rainbow trout (Oncorhynchus mykiss) to waterborne copper in light of recent evidence of interactions between sodium and copper metabolism in the gills. Trout were maintained for 6 days on one of four diets of increasing sodium concentration (0.25 mmol g-1, 0.51 mmol g-1, 0.76 mmol g-1 and 1.27 mmol g-1, which corresponds to 0.6%, 1.2%, 1.8% and 3% sodium by mass, respectively). At the end of 7 days, fish were exposed for 6 h to waterborne copper spiked with 64Cu to determine if the dietary sodium affected responses to a subsequent short-term waterborne copper exposure. The radiotracer allowed us to distinguish between Cu occurring in fish tissues before the experiment and `newly accumulated' Cu arising from the experimental exposure. Dietary sodium concentrations of 1.8% or 3% reduced newly accumulated copper concentrations in gill (from 93.9 ng g-1in control to 38.9 ng g-1 and 20.0 ng g-1 in fish fed 1.8% or 3% Na+-supplemented diets, respectively), liver (from 64.3 ng g-1 to 23.1 ng g-1 and 7.5 ng g-1,respectively), kidney (from 29.3 ng g-1 to 11.7 ng g-1and 7.8 ng g-1, respectively), plasma (from 64.7 ng g-1to 21.5 ng g-1 and 10.7 ng g-1, respectively) and gut(from 6.8 ng g-1 to 3.4 ng g-1 and 2.2 ng g-1, respectively) by 50.0-88.2%. The 3%Na+-supplemented diets also increased plasma and gut sodium concentrations by 38.1% (from 137.1 μmol g-1 to 189.3 μmol g-1) and 104.3% (from 56.5 μmol g-1 to 115.4 μmol g-1), respectively, relative to fish maintained on untreated diets. Whole body uptake rates of both sodium and copper were significantly reduced,and highly correlated (r=0.97) with one another, in fish fed high-sodium diets relative to controls. Moreover, sodium efflux was 12% and 38% higher in fish fed 1.8% and 3% sodium-enriched diets, respectively. Fish fed high-sodium diets also drank more water, but the contribution of drinking to waterborne copper uptake was negligible. From these results, we speculate that, at least in part, aqueous sodium and copper share a common branchial uptake route, probably through an apical sodium channel. According to this hypothesis, as the channel is downregulated with increasing internal sodium concentrations, both sodium and copper uptake from the water are inhibited.
Cloning of rainbow trout (Oncorhynchus mykiss) α-actin,myosin regulatory light chain genes and the 5′-flanking region ofα-tropomyosin. Functional assessment of promoters
Authors: Krasnov Aleksei , Teerijoki Heli , Gorodilov Yuri , Mölsä Hannu
Published: January 2003

We report PCR cloning of rainbow trout α-actin (α-OnmyAct),myosin regulatory light chain (OnmyMLC2) genes and the 5′-flanking region of α-tropomyosin (α-OnmyTM). Being expressed in skeletal and cardiac muscle, α-OnmyAct was a predominant isoform in trunk muscle of adult rainbow trout. Exon structure of this gene was identical to all known vertebrate skeletal and to some of the cardiac α-Act genes. Two distinct OnmyMLC2 promoters were cloned and both included transposon-like sequences. The coding part of OnmyMLC2 consisted of seven exons whose length was typical for vertebrate MLC2 genes. The upstream regions of α-OnmyAct and OnmyMLC2 included a TATA box and a number of putative regulatory motifs(E-boxes in all three sequences and CArG-boxes in α-OnmyAct), whereas there were no canonical motifs in the α-OnmyTM promoter. LacZ reporter gene was fused with the 5′-flanking regions of α-OnmyAct, two OnmyMLC2 genes and α-OnmyTM promoters. These constructs were transferred into rainbow trout eggs. At the stage of 39 somite pairs, LacZ reporter was detected in the myotomes, neural plate and neural crest, brain and yolk syncytial layer of all analysed embryos. α-OnmyTMLacZ was also expressed in the heart. Functionality of promoters and the α-OnmyAct terminator was confirmed in rainbow trout primary embryonic cell cultures. We cloned rainbow trout glucose transporter type I (OnmyGLUT1) into vectors including the α-OnmyAct and OnmyMLC2 promoters and the α-SkAct terminator. Recombinant OnmyGLUT1 transcripts were detected in rainbow trout embryos during somitogenesis.
Volumetric and ionic responses of goldfish hepatocytes to anisotonic exposure and energetic limitation
Authors: Espelt M. V. , Mut P. N. , Amodeo G. , Krumschnabel G. , Schwarzbaum P. J.
Published: January 2003

The relationship between cell volume and K+ transmembrane fluxes of goldfish (Carassius auratus) hepatocytes exposed to anisotonic conditions or energetic limitation was studied and compared with the response of hepatocytes from trout (Oncorhynchus mykiss) and rat (Rattus rattus). Cell volume was studied by video- and fluorescence microscopy,while K+ fluxes were assessed by measuring unidirectional 86Rb+ fluxes.

In trout and rat hepatocytes, hyposmotic (180 mosmoll-1)exposure at pH 7.45 caused cell swelling followed by a regulatory volume decrease (RVD), a response reported to be mediated by net efflux of KCl and osmotically obliged water. By contrast, goldfish hepatocytes swelled but showed no RVD under these conditions. Although in goldfish hepatocytes a net(86Rb+)K+ efflux could be activated by N-ethylmaleimide, this flux was not, or only partially, activated by hyposmotic swelling (120-180 mosmoll-1).

Blockage of glycolysis by iodoacetic acid (IAA) did not alter cell volume in goldfish hepatocytes, whereas in the presence of cyanide (CN-),an inhibitor of oxidative phosphorylation, or CN- plus IAA(CN-+IAA), cell volume decreased by 3-7%. Although in goldfish hepatocytes, energetic limitation had no effect on(86Rb+)K+ efflux,(86Rb+)K+ influx decreased by 57-66% in the presence of CN- and CN-+IAA but was not significantly altered by IAA alone. Intracellular K+ loss after 20 min of exposure to CN- and CN-+IAA amounted to only 3% of the total intracellular K+.

Collectively, these observations suggest that goldfish hepatocytes, unlike hepatocytes of anoxia-intolerant species, avoid a decoupling of transmembrane K+ fluxes in response to an osmotic challenge. This may underlie both the inability of swollen cells to undergo RVD but also the capability of anoxic cells to maintain intracellular K+ concentrations that are almost unaltered, thereby prolonging cell survival.
Five-year results of curettage-cryosurgery for 100 consecutive auricular non-melanoma skin cancers
Authors: Nordin Peter , Stenquist Bo
Published: January 2003

Large excisions or Mohs’ micrographic surgery (MMS) are often the suggested treatments for non-melanoma skin cancers (NMSCs) of the external ear. This five-year follow-up attempts to evaluate whether curettage-cryosurgery could be an alternative therapy for selected auricular NMSCs.

One hundred auricular NMSCs, selected at a skin tumour clinic, were treated by a thorough curettage, with different-sized curettes, followed by cryosurgery in a double freeze-thaw cycle. Seventy-seven basal cell carcinomas (BCCs), 13 squamous cell carcinomas (SCCs), six SCCs in situ, and four basosquamous carcinomas were included. The mean diameter of the tumours was 18 mm (range 5–70). Morphoeiform BCCs, recurrent BCCs with fibrotic component, and most of the SCCs were selected for MMS.

Seventy-one patients with 81 tumours were followed-up for at least five years with only one recurrence. Nineteen patients with 19 tumours, followed-up for two to four years, died from other causes with no sign of recurrence at their last visit. Patients followed-up for less than two years were excluded. No major problems were registered after treatment. The cosmetic result was good or acceptable in most patients.

In carefully selected patients a thorough curettage followed by freezing with liquid nitrogen in a double freeze-thaw cycle could be a safe and inexpensive therapy even for large NMSCs of the external ear.
Predicting information flows in network traffic
Authors: Hinich Melvin J. , Molyneux Robert E.
Published: January 2003

In optimizing information flows in networks, it would be useful to predict aspects of the network traffic. Yet, the notion of predicting network traffic does not appear in the relevant literature reporting analysis of network traffic. This literature is both well developed and skeptical about the value of traditional time series analysis on network data. It has consistently reported three “traffic invariants” in the analysis of network and Internet traffic. This study uses such time series analysis on a day's worth of Internet log data and finds poor support for one of the invariants. In the preliminary analysis, evidence of nonlinearity was discovered in these data and the analysis presented here examines this question further. This study posits that nonlinear events may be a traffic invariant although this hypothesis would have to be investigated further. The appearance of nonlinear structures is important to the question of predicting network traffic because there are currently no methods to predict time series with nonlinear structures. The discovery of nonlinear structures, then, may mean that developing a predictive model is impossible with current techniques. On the other hand, these nonlinearities may result from interactions from other OSI Layers than the one studied.
Open source software development and Lotka's Law: Bibliometric patterns in programming
Authors: Newby Gregory B. , Greenberg Jane , Jones Paul
Published: January 2003

This research applies Lotka's Law to metadata on open source software development. Lotka's Law predicts the proportion of authors at different levels of productivity. Open source software development harnesses the creativity of thousands of programmers worldwide, is important to the progress of the Internet and many other computing environments, and yet has not been widely researched. We examine metadata from the Linux Software Map (LSM), which documents many open source projects, and Sourceforge, one of the largest resources for open source developers. Authoring patterns found are comparable to prior studies of Lotka's Law for scientific and scholarly publishing. Lotka's Law was found to be effective in understanding software development productivity patterns, and offer promise in predicting aggregate behavior of open source developers.
Synthesis of 3‐tert‐butylcatechol by an engineered monooxygenase
Authors: Meyer Andreas , Held Martin , Schmid Andreas , Kohler Hans‐Peter E. , Witholt Bernard
Published: January 2003

Recombinant Escherichia coli JM101 was used for the in vivo biocatalytic synthesis of 3‐tert‐butyl‐ catechol. The bacterial strain synthesized the laboratory‐evolved variant HbpAT2 of 2‐hydroxybiphenyl 3‐monooxygenase (HbpA, EC 1.14.13.44) from Pseudomonas azelaica HBP1. The mutant enzyme HbpAT2 is able to hydroxylate 2‐tert‐butylphenol to the corresponding catechol, a reaction that is not catalyzed by the wild‐type enzyme. The biotransformation was performed in a 3‐L bioreactor for 24 h. To mitigate the toxicity of the 2‐tert‐butylphenol starting material, we applied a limited substrate feed. Continuous in situ product removal with the hydrophobic resin Amberlite™ XAD‐4 was used to separate the product from culture broth. In addition, binding to the resin stabilized the product, which was important because 3‐tert‐butylcatechol is very labile in aqueous solution. The productivity of the process was 63 mg L−1 h−1 so that after 24 h, 3.0 g of 3‐tert‐butylcatechol were isolated. Down‐stream processing consisted of two steps. First, bound 2‐tert‐butylphenol and 3‐tert‐butylcatechol were eluted from Amberlite™ XAD‐4 with methanol. Second, the two compounds were separated over neutral aluminum oxide, which selectively binds the produced catechol but not the phenol substrate. The final purity of 3‐tert‐butylcatechol was greater than 98%. © 2003 Wiley Periodicals, Inc. Biotechnol Bioeng 81: 518–524, 2003.
Optimizing chemotherapy by measuring reversal of P‐glycoprotein activity in plasma membrane vesicles
Authors: Köhler Sabine , Stein Wilfred D.
Published: January 2003

The appearance of multidrug resistance (MDR) of cancer cells is a major obstacle to successful chemotherapy. Several proteins have been identified that pump chemotherapeutic drugs out of cells, thus bringing about MDR. One representative pump is the P‐glycoprotein, whose function can be inhibited by blockers (also known as reversers, modulators or chemosensitizers). In clinical application, many of these blockers are often not effective because they become bound to the plasma of the patients. The extent of plasma binding of the blocker varies in different persons and we have developed a 96‐well kit to assay such inter‐person differences. The assay uses membrane vesicles isolated from a human lymphoblastoid cell line (CEM Col1000). Uptake of rhodamine into the vesicles was measured with different concentrations of the blockers verapamil and XR9576 in presence of human plasma. The reverser XR9576 is nearly 30 times more effective than the classical blocker verapamil, the relevant Km values ranging from 2.66 to 45 nM for XR 9576 and 0.7 to 5.5 μM for verapamil. An even greater difference between these two drugs, nearly 1000‐fold, could be shown also in intact cells by calcein AM uptake experiments. © 2003 Wiley Periodicals, Inc. Biotechnol Bioeng 81: 507–517, 2003.
Effect of deletion of chitin synthase genes on mycelial morphology and culture viscosity in Aspergillus oryzae
Authors: Müller Christian , Hansen Kim , Szabo Peter , Nielsen Jens
Published: January 2003

The objective of this study was to quantify the effect of disrupting two chitin synthases, chsB and csmA, on the morphology and rheology during batch cultivation of Aspergillus oryzae. The rheological properties were characterized in batch cultivations at different biomass concentrations (from 3.4–22.5 g kg−1 biomass) and the power‐law model adequately described the rheological properties. In the cultivations there were pellets, clumps, and freely dispersed hyphal elements. The different morphological fractions were quantified using image analysis. The apparent viscosity of the fermentation broth was significantly affected by the biomass concentration, the morphology, and also by pH. The chsB disruption strain had lower consistency index K values for all biomass concentrations investigated, which is a desirable trait for industrial Aspergillus fermentations. © 2003 Wiley Periodicals, Inc. Biotechnol Bioeng 81: 525–534, 2003.
Effect of nitrite and nitrate on in situ sulfide production in an activated sludge immobilized agar gel film as determined by use of microelectrodes
Authors: Okabe Satoshi , Santegoeds Cecilia M. , De Beer Dirk
Published: January 2003

Microelectrode, fluorescence in situ hybridization (FISH), and denaturing gradient gel electrophoresis (DGGE) analyses were used to investigate the effect of nitrite and nitrate on in situ sulfide production in an activated sludge immobilized agar gel film. Microelectrode measurements of O2, H2S, NO3−, NO2−, and pH revealed that the addition of NO2− and NO3− forced sulfate reduction zones deeper in the agar gel and significantly reduced the in situ sulfide production levels. The sulfate reduction zone was consequently separated from O2 and NO2− or NO3− respiration zones with increasing the concentrations of NO2− and NO3−. These NO2− and NO3− treatments had only a transient effect on sulfide production. The in situ sulfide production quickly recovered to the previous levels when NO2− and NO3− were removed. The PCR‐DGGE and FISH analyses revealed that 2‐day‐continuous addition of 500 μM NO3− did not change the metabolically active sulfate‐reducing bacterial (SRB) community. On the basis of these data, it could be concluded that the addition of NO2− and NO3− did not kill SRB, but induced the interspecies competition for common carbon source (i.e., acetate) between nitrate‐reducing heterotrophic bacteria and SRB and enhanced the oxidation of the produced sulfide, which were main possible causes of the suppression of in situ sulfide production in the agar gel. © 2003 Wiley Periodicals, Inc. Biotechnol Bioeng 81: 570–577, 2003.
Alphavirus cDNA‐based expression vectors: Effects of RNA transcription and nuclear export
Authors: Boorsma Marco , Saudan Philippe , Pfruender Holger , Bailey James E. , Schlesinger Sondra , Renner Wolfgang A. , Bachmann Marlin F.
Published: January 2003

The construction of layered DNA–RNA replicons has facilitated and expanded the use of alphavirus vectors to vaccine development, construction of packaging cell lines and long‐term heterologous gene expression. In these vector systems, the alphavirus replicon is under the control of a strong RNA polymerase II promoter and replicon RNA is transcribed from DNA before transport to the cytoplasm. Efficient RNA amplification catalyzed by the viral replicase results in high levels of mRNA and the recombinant protein. Recently, we developed a temperature‐regulated Sindbis replicon‐based DNA expression system characterized by a linear increase of expression upon decrease of the temperature from 37°C to 29°C. Modifications known to affect transcription and nuclear export of RNA led to a 5‐fold increase in expression in BHK cells and up to over 80‐fold increase in CHO cells and BF fibroblasts in transient transfection experiments. Furthermore, reducing cell proliferation resulted in a further 2‐ to 3‐fold higher expression. While increased expression per cell was responsible for some of the enhanced production, it was primarily the number of expressing cells that made the difference in most cell lines. Further experiments indicated that a threshold amount of replicon RNA had to reach the cytoplasm in order for replication to occur. Thus, alterations that improve transcription, nuclear export and stability of the RNA had a significant impact on protein production in the pCytTS expression system and probably in other layered DNA‐based viral vectors. Furthermore the results indicate that RNA replication is differentially regulated in DNA layered RNA replicons versus viral infection. © 2003 Wiley Periodicals, Inc. Biotechnol Bioeng 81: 553–562, 2003.
DNA purification by triple‐helix affinity precipitation
Authors: Costioli Matteo D. , Fisch Igor , Garret‐Flaudy Frédéric , Hilbrig Frank , Freitag Ruth
Published: January 2003

Recent advances in DNA‐based medicine (gene therapy, genetic vaccination) have intensified the necessity for pharmaceutical‐grade plasmid DNA purification at comparatively large scales. In this contribution triple‐helix affinity precipitation is introduced for this purpose. A short, single‐stranded oligonucleotide sequence (namely (CTT)7), which is capable of recognizing a complementary sequence in the double‐stranded target (plasmid) DNA, is linked to a thermoresponsive N‐isopropylacrylamide oligomer to form a so‐called affinity macroligand (AML). At 4°C, i.e., below its critical solution temperature, the AML binds specifically to the target molecule in solution; by raising the temperature to 40°C, i.e., beyond the critical solution temperature of the AML, the complex can be precipitated quantitatively. After redissolution of the complex at lower temperature, the target DNA can be released by a pH shift to slightly alkaline conditions (pH 9.0). Yields of highly pure (plasmid) DNA were routinely between 70% and 90%. Non‐specific co‐ precipitation of either the target molecule by the non‐activated AML precursor or of contaminants by the AML were below 7% and presumably due to physical entrapment of these molecules in the wet precipitate. Ligand efficiencies were at least 1 order of magnitude higher than in triple‐helix affinity chromatography. © 2003 Wiley Periodicals, Inc. Biotechnol Bioeng 81: 535–545, 2003.
Microfluidic peroxidase biochip for polyphenol synthesis
Authors: Srinivasan Aravind , Wu Xiaoqiu , Lee Moo‐Yeal , Dordick Jonathan S.
Published: January 2003

An enzyme‐containing microfluidic biochip has been developed for the oxidative polymerization of phenols. The biochip consists of a simple T‐junction with two feed reservoirs 20 mm apart and a microreaction channel 30 mm long. The channel is 15 μm deep and 200 μm wide at the center, giving a reaction volume of 90 nL. The biochip was fabricated using conventional photolithographic methods on a glass substrate etched using a HF‐based solution. Fluid transport was enabled using electroosmotic flow. Soybean peroxidase was used as the phenol oxidizing catalyst, and in the presence of p‐cresol and H2O2, essentially complete conversion of the H2O2 (the limiting substrate) occurred in the microchannel at a flow rate of ca. 290 nL/min. Thus, peroxidase was found to be intrinsically active even upon dramatic scale‐down as achieved in microfluidic reactors. These results were extended to a series of phenols, thereby demonstrating that the microfluidic peroxidase reactor may have application in high‐throughput screening of phenolic polymerization reactions for use in phenolic resin synthesis. Finally, rapid growth of poly(p‐cresol) on the walls of the microreaction channel could be performed in the presence of higher H2O2 concentrations. This finding suggests that solution‐phase peroxidase catalysis can be used in the controlled deposition of polymers on the walls of microreactors. © 2003 Wiley Periodicals. Biotechnol Bioeng 81: 563–569, 2003.
Uptake of macrominerals and trace elements by the cyanobacterium Spirulina platensis (Arthrospira platensis PCC 8005) under photoautotrophic conditions: Culture medium optimization
Authors: Cogne Guillaume , Lehmann Bernd , Dussap Claude‐Gilles , Gros Jean‐Bernard
Published: January 2003

Uptake rates of macrominerals and trace elements were characterized in batch and continuous cultures of Spirulina platensis under photoautotropic conditions. The values of yield coefficients were determined using inductively coupled plasma emission spectroscopy (ICP‐ES). Further simplifications of culture medium proved possible, mainly in the trace element solutions; concentrations of some elements were lowered and trace elements B, Mo, V, Cr, Ni, Co, W, and Ti were removed. © 2003 Wiley Periodicals, Inc. Biotechnol Bioeng 81: 588–593, 2003.
Composite surface for blocking bacterial adsorption on protein biochips
Authors: Huang Tom T. , Sturgis Jennifer , Gomez Rafael , Geng Tao , Bashir Rashid , Bhunia Arun K. , Robinson J. Paul , Ladisch Michael R.
Published: January 2003

The design and fabrication of protein biochips requires characterization of blocking agents that minimize nonspecific binding of proteins or organisms. Nonspecific adsorption of Escherichia coli, Listeria innocua, and Listeria monocytogenes is prevented by bovine serum albumin (BSA) or biotinylated BSA adsorbed on SiO2 surfaces of a biochip that had been modified with a C18 coating. Biotinylated BSA forms a protein‐based surface that in turn binds streptavidin. Because streptavidin has multiple binding sites for biotin, it in turn anchors other biotinylated proteins, including antibodies. Hence, biotinylated BSA simultaneously serves as a blocking agent and a foundation for binding an interfacing protein, avidin or streptavidin, which in turns anchors biotinylated antibody. In our case, the antibody is C11E9, an IgG‐type antibody that binds Listeria spp. Nonspecific adsorption of another bacterium, Escherichia coli, is also minimized due to the blocking action of the BSA. The blocking characteristics of BSA adsorbed on C18‐derivatized SiO2 surfaces for construction of a protein biochip for electronic detection of pathogenic organisms is investigated. © 2003 Wiley Periodicals, Inc. Biotechnol Bioeng 81: 618–624, 2003.
Investigations on 1,5‐diaminoanthraquinone by laser excitation
Authors: Umadevi M. , Ramakrishnan V.
Published: January 2003

Optical absorption and fluorescence emission spectra of 1,5‐diaminoanthraquinone (1,5‐DAAQ) in different solvents and the surface‐enhanced Raman scattering (SERS) spectrum of 1,5‐DAAQ in silver sol were investigated. Optical absorption and fluorescence emission studies revealed that the internal and external hydrogen bonds and reorientation of the solvent molecule around the excited state fluorophore are responsible for the observed bathochromic shift and the non‐radiative decay process in polar solvents. SERS studies showed that 1,5‐DAAQ molecules are chemisorbed through carbonyl groups and the lone pair of electrons on the nitrogen. The orientation of the molecule on the silver surface is found to be stand‐on. Copyright © 2002 John Wiley & Sons, Ltd.
Vibrational spectra and structures of fluoroalkyl and fluoroaryl compounds of tellurium: Te2(CF3)2, Te2(C6F5)2 and Te(C6F5)2
Authors: Hoge B. , Naumann D. , Pohl H. , Shamir J.
Published: January 2003

Raman and infrared spectra of Te2(CF3)2, Te2(C6F5)2 and Te(C6F5)2 were studied and their structures determined. Polarization measurements of Raman lines of the neat liquid Te2(CF3)2 and of CCl4 solutions of Te2(C6F5)2 and Te(C6F5)2 were also performed, allowing the assignment of symmetric and asymmetric vibrations. The observed coinciding wavenumbers supported the skeletal C2 symmetry structure for the Te2R2 compounds. Copyright © 2002 John Wiley & Sons, Ltd.
Raman spectroscopic study of phase transitions in Li3PO4
Authors: Popović L. , Manoun B. , de Waal D. , Nieuwoudt M. K. , Comins J. D.
Published: January 2003

Although three forms of lithium phosphate are known, a complete structural description of the highest temperature polymorph has not yet been given. In the present work, the phase transitions of lithium phosphate were investigated at high temperatures using Raman microscopy and x‐ray powder diffraction. Both transitions were observed by following the temperature dependence of the totally symmetrical Raman stretching vibration of PO43−. Currently available structural information on the α form, resulting in P—O bond lengths of 1.787–1.899 Å, as determined by valence bond calculations, are disputed here. A correlation between Raman wavenumber and bond length in inorganic phosphates estimates the P—O bond length in α‐Li3PO4 to be around 1.57(1) Å, which is in closer agreement with values for other orthophosphates of between 1.50 and 1.58 Å. Copyright © 2002 John Wiley & Sons, Ltd.
Seasonal changes in phospholipids of mussel (Mytilus edulis Linne)
Authors: Lin Hong , Jiang Jie , Xue Chang‐hu , Zhang Bin , Xu Jia‐chao
Published: January 2003

The phospholipids of mussels (Mytilus edulis Linne) from the coast of Qingdao were extracted, fractionated and analysed over a 12 month period. The contents of total lipids, neutral lipids, polar lipids and phospholipids were measured. The composition of phospholipids was determined by high‐performance liquid chromatography, and their fatty acid composition was analysed by gas chromatography. The phospholipid content ranged from 3.6 to 6.4 g kg−1 soft tissue. PE (phosphatidyl ethanolamine) and PC (phosphatidyl choline) were the major constituents. C16:0, C20:5 and C22:6 were the major fatty acids. C20:5 (5.25–23.10%) and C22:6 (6.05–20.42%) varied regularly with the seasonal factors. Their total amounts were high from January to June, which would be an optimal time for the utilisation of the phospholipids of mussels.

© 2002 Society of Chemical Industry
Pastoral and species flavour in lambs raised on pasture, lucerne or maize
Authors: Young Owen A , Lane Geoffrey A , Priolo Alessandro , Fraser Karl
Published: January 2003

Variations in diet, age and castration were employed to generate a range of flavours that were chemically analysed to find the cause of ‘pastoral’ flavour in sheepmeat and its relationship to species flavour. Lambs were raised on pasture (ram or castrate) or on a maize‐based or lucerne‐based concentrate diet (ram only). They were slaughtered at 132 and 232 days. Fat from animals raised on concentrates had lower proportions of fat‐hardening stearic acid and higher proportions of oxidation‐prone fat‐softening oleic and linoleic acids. Concentrations of species‐characterising short branched‐chain fatty acids (BCFAs), typified by 4‐methyloctanoic acid, were lower for pasture‐fed lambs, particularly at 232 days, although between‐animal variation was high. Castration did not statistically affect BCFA concentration at this age. Correlations between BCFAs and testes weight were not significant, suggesting that they were not acting as sex pheromones. Concentrations of 3‐methylindole (skatole) in perirenal fat were higher for the pasture diet at both slaughter dates. Concentrations of 4‐methylphenol in the fat were not affected by diet. However, 3‐methylphenol was more abundant in pasture treatments. A sensory panel found that the intensity of ‘sheepmeat’ flavour was higher for pasture‐raised animals, but that associations of ‘barnyard’ flavour (which has been linked to pastoral flavour) with diet were more complex. The issue was resolved by fat sniffing. Panel responses to heated subcutaneous fat were recorded as frequency of descriptive terms drawn from a limited lexicon. Volatiles from fats pooled by treatment were resolved on a gas chromatographic column whose effluent was monitored by odourport sniffing. Compounds were identified by parallel chromatographic/mass spectrometric runs. The headspace concentrations of these compounds were then measured for individual animals. These data were related to frequency data by the principal component method. ‘Mutton’ and ‘sheepmeat’ odour notes were clearly linked to indoles (skatole particularly) and, to a lesser extent, methylphenol, setting these notes apart from ‘lamb’, an odour note more associated with lucerne and maize diets through higher concentrations of BCFAs. It was concluded that 3‐methylindole was the major cause of pastoral flavour in sheepmeat, and that fat oxidation products represented a background flavour that varied quantitatively but not qualitatively with fatty acid profile.

© 2002 Society of Chemical Industry
Hydration and physicochemical properties of small‐particle cassava starch
Authors: Sanguanpong Varangkana , Chotineeranat Sunee , Piyachomkwan Kuakoon , Oates Christopher G , Chinachoti Pavinee , Sriroth Klanarong
Published: January 2003

Acid hydrolysis followed by ball milling was applied to cassava starch in order to fracture the granules. Lintnerisation led to degradation first in the amorphous domains and increased the crystallinity. The resulting increase in internal defects and brittleness made the granules more susceptible to breakage upon milling. Ball milling, although leading to some degree of crystallinity loss, could effectively reduce the size of acid‐hydrolysed starch while the total double helix remained relatively unchanged. The resulting small‐particle starch was structurally more heterogeneous (wider Tm range). Swelling of small‐particle starch was accompanied by solubilisation of water‐soluble fragments at a temperature greater than 60 °C. The properties of individual granules are strongly influenced by the hydration and physicochemical properties of their amorphous and crystalline domains.

© 2002 Society of Chemical Industry
Effect of microbial transglutaminase on rheological properties of oxidised and non‐oxidised natural actomyosin from two species of bigeye snapper
Authors: Visessanguan Wonnop , Benjakul Soottawat , Tanaka Munehiko
Published: January 2003

The contribution of microbial transglutaminase (MTGase) to the thermal gelation of non‐oxidised and oxidised natural actomyosin (NAM) from two species of bigeye snapper was studied by dynamic rheological testing. Under two‐step heating, the addition of MTGase increased the gel‐forming ability of both species. During setting at 40 °C, Priacanthus macracanthus NAM seemed to show higher reactivity to MTGase than P tayenus NAM, resulting in a higher rate and magnitude of G′ development. An increase in final G′ of NAM from P macracanthus and P tayenus by 13.7–24 and 6.6–10.8 times respectively was observed compared with NAM alone. Iron‐catalysed oxidation substantially decreased the gel‐forming ability of P tayenus NAM but enhanced that of P macracanthus NAM. However, oxidation decreased the reactivity of both NAM types to added MTGase. The results suggested that the native NAM structure was essential for MTGase to maximise the setting response. The gel‐forming ability and setting response of denatured NAM were partially recovered by the addition of MTGase.

© 2002 Society of Chemical Industry
Comparison of gilthead sea bream (Sparus aurata) and hake (Merluccius merluccius) muscle proteins during iced and frozen storage
Authors: Tejada Margarita , Huidobro Almudena , Mohamed Gamal Fouad
Published: January 2003

Gilthead sea bream (Sparus aurata) and hake (Merluccius merluccius) muscle behave differently during storage, whether in ice or deep frozen. Rapid changes have been observed in the texture of hake muscle during frozen storage, while gilthead sea bream has proved to be more stable. In order to ascertain the role of muscle proteins in the changes observed during storage, parameters related to protein functionality and the properties of extracted natural actomyosin (NAM) were studied initially and during storage in ice or at −20 °C. Initially, the parameters related to functionality had higher values in hake muscle and extracted NAM than in gilthead sea bream. At the end of iced storage (22 days), less myosin heavy chain (MHC) and actin were extracted from hake, but there was practically no change in gilthead sea bream. This decrease was not accompanied by lower Ca2+‐ATPase activity. Freezing produced no drastic changes, with lower values for gilthead sea bream. However, this species was more stable after 1 year, except for the Ca2+‐ATPase activity of NAM. This suggests that the changes that hake proteins underwent during storage particularly affected properties related to aggregation, whereas in gilthead sea bream the changes hardly affected the formation of soluble or insoluble aggregates but did affect the active sites of myosin.

© 2002 Society of Chemical Industry
A new video compression algorithm for different videoconferencing standards
Authors: Al‐Asmari Awad Kh.
Published: January 2003

In this paper, a new and simple predictive coding algorithm for video compression and multimedia communication for different network applications is investigated. This algorithm is called semi‐hexagonal absolute moment block truncation coding (SH‐AMBTC). It enjoys better objective and subjective qualities over the standard square shaped AMBTC. This technique based on the prediction of the bit‐map of the middle frames in a sequence from the bit‐map of the end frames (the first and the last frames in the group). It is of very low complexity comparing to the standard algorithm MPEG. The new algorithm adds no complexity to the existing AMBTC algorithm. Copyright © 2002 John Wiley & Sons, Ltd.
Global optimization of SDH networks: a practical application
Authors: Beckmann Dirk , Thurow Jörn
Published: January 2003

We describe in this paper how the backbone network of a major German telecommunication company has been globally optimized using the so‐called branch‐and‐bound algorithm. The described optimization approach enables significant reductions of expenses for leased lines compared to manually derived planning results. This gain achieved by the presented optimization approach is also demonstrated by the comparison with a heuristic algorithm which is used for the simulation of a human network planning process. Copyright © 2002 John Wiley & Sons, Ltd.
The effects of badly behaved routers on Internet congestion
Authors: Curran Kevin , Woods Derek , McDermot Nadene , Bradley Colleen
Published: January 2003

From an exhaustive series of trace packets to a diverse set of destinations, our research has discovered that specific routers are the cause of bottlenecks in the Internet. We found that packets took the same route each time towards their destination. Our research has also found that over periods as large as seven days these routers continue to cause bottlenecks with no re‐routing of packets to alleviate congestion. This research begs the question as to why these bottlenecks occur at the same places and for so long a period and also queries the extent of implementation of dynamic routing algorithms. Copyright © 2002 John Wiley & Sons, Ltd.
School adjustment of first‐generation Chinese‐American adolescents
Authors: Zhou Zheng , Peverly Stephen T. , Xin Tao , Huang Annie S. , Wang Weidong
Published: January 2003

Guided by Perry and Weinstein's (1998) conceptual model of school adjustment, first‐generation Chinese‐American adolescents' school adjustment was compared with that of Mainland Chinese and European American adolescents in two domains of functioning, academic (attitudes to school and teacher; their sense of academic adequacy) and behavioral (depression, anxiety and social stress), using the Behavioral Assessment System for Children (BASC). Results indicated that Chinese‐American adolescents reported more negative attitudes toward teachers than European American and Mainland Chinese students, had more negative perceptions of the school environment than students in Mainland China, and reported more feelings of inadequacy in academics than European American students. Chinese‐American adolescents reported higher levels of depression and social stress than the other two groups, and more anxiety than Mainland Chinese students. Feelings of academic inadequacy were related to depression, anxiety and social stress for all three cultural groups. In addition, Chinese‐American adolescents reported that they did not trust their teachers and their peers who were not Chinese‐American, and felt that adults at school and home did not understand them. This feeling coupled with their fear, anger and frustration at being bullied frequently in school could be related to Chinese‐American adolescents' negative perception of school and teachers. Implications of the study are discussed. © 2003 Wiley Periodicals, Inc. Psychol Schs 40: 71–84, 2003.
Societal and school influences on student creativity: The case of China
Authors: Niu Weihua , Sternberg Robert J.
Published: January 2003

Chinese students outperform American students in many international competitions in mathematics and the natural sciences. Does this superiority of Chinese students over American students also apply in other domains? Our previous research has shown that compared with their American counterparts, Chinese students' artwork is perceived as less creative by both Chinese and American judges. In a new study, we find that Chinese students' creativity is increased when given direct instructions to be creative or guidance on how to be creative. Three different factors are posited to be responsible for the discrepancy in rated creativity between Chinese and American students, namely, social values, school pedagogic practices, and educational testing systems. This article argues that high‐stakes standardized tests could impair the development of students' creativity. Although there is a general tendency for school educators in both China and the United States to overemphasize analytical skills at the expense of the development of creative abilities, in general, the tendency for the Chinese to do so is stronger than it is for the American. Suggestions are proposed to educators on how to foster students' creativity. Furthermore, the article suggests that school and national leaders in the United States and China, as well as elsewhere, should learn from one another's educational successes, while maintaining their unique cultural and educational characteristics. © 2003 Wiley Periodicals, Inc. Psychol Schs 40: 103–114, 2003.
Social moral reasoning in Chinese children: A developmental study
Authors: Fang Ge , Fang Fu‐xi , Keller Monika , Edelstein Wolfgang , Kehle Thomas J. , Bray Melissa A.
Published: January 2003

The present study investigated developmental changes in moral reasoning about sibling and parental relationships in Mainland Chinese children. More specifically, motives of a protagonist with conflicting obligations in the family were examined. Results suggested universal stage‐like progression in moral judgment from superficial (stages 1 and 2) to profound (stage 3). However, culture‐specific moral reasoning also existed. For example, in comparison to children in Kohlberg's studies, Chinese children's moral decisions emphasized respect for authority, altruism, and concern over their sibling's moral correctness. The authors argued that Chinese children's moral characteristics are influenced by the cultural context. © 2003 Wiley Periodicals, Inc. Psychol Schs 40: 125–138, 2003.