bluuebunny/crossref_metadata_2025 huggingface dataset:
Ground‐penetrating radar facies as an aid to sequence stratigraphic analysis: application to the archaeology of Clonmacnoise Castle, Ireland
Authors: Ruffell Alastair , Geraghty Louise , Brown Colin , Barton Kevin
Published: November 2004

This paper describes the advantages of interpreting ground‐penetrating radar (GPR) facies in a sequence stratigraphic context. These data have been collected adjacent to the River Shannon at Clonmacnoise Castle in central Ireland and demonstrate that stratigraphy is not necessarily made up of horizontal isochronous surfaces; some reflective surfaces are more important than others in interpretation and that two‐dimensional sections must be interpreted with caution. Radar facies analysis and thus sequence stratigraphy can be used to both interpret the sedimentary record in terms of palaeoenvironments as well as identify important (key) surfaces. Bright, continuous surfaces are often found at horizons of palaeoenvironmental change and have distinctive reflector shapes and terminations (or stratal patterns) above and below. Such stratal patterns define and reflect linked fluvial and human environments that have developed and been preserved through the creation of accommodation space. Key surfaces have been identified when sedimentation was altered, thus reflecting a natural or anthropogenic palaeoenvironmental change. In anthropogenically modified or created successions, such as those seen at Clonmacnoise, key surfaces have produced changes in dielectric constants in the sediments that are seen as radar reflections. Natural activity includes lateral migration of point‐bars and fluvial onlap. Anthropogenic activity has created accommodation space (the moat), a major sequence boundary and subdwelling surface disruption of reflectors. A pre‐moat fault can be observed on GPR data that is along strike of a surface scarp to the southwest of Clonmacnoise Castle. The results demonstrate the enhanced interpretive and predictive use of radar facies in sequence stratigraphy. Copyright © 2004 John Wiley & Sons, Ltd.
Lipopolysaccharide‐induced expression of multiple alternatively spliced MEFV transcripts in human synovial fibroblasts: A prominent splice isoform lacks the C‐terminal domain that is highly mutated in familial mediterranean fever
Authors: Diaz Arturo , Hu Chunbo , Kastner Daniel L. , Schaner Philip , Reginato Anthony M. , Richards Neil , Gumucio Deborah L.
Published: November 2004

Objective

To investigate the expression of the familial Mediterranean fever (FMF) gene (MEFV) in human synovial fibroblasts.

Methods

MEFV messenger RNA in synovial fibroblasts, chondrocytes, and peripheral blood leukocytes (PBLs) was analyzed by semiquantitative and real‐time polymerase chain reaction and ribonuclease protection assay. The subcellular localization of pyrin, the MEFV product, was determined in transfected synovial fibroblasts and HeLa cells with plasmids encoding pyrin isoforms. Native pyrin was detected with an antipyrin antibody.

Results

MEFV was expressed in synovial fibroblasts, but not in chondrocytes. Four alternatively spliced transcripts were identified: an extension of exon 8 (exon 8ext) resulting in a frameshift that predicts a truncated protein lacking exons 9 and 10, the addition of an exon (exon 4a) predicting a truncated protein at exon 5, the in‐frame substitution of exon 2a for exon 2, and the previously described removal of exon 2 (exon 2Δ). Exon 8ext transcripts represented 27% of the total message population in synovial fibroblasts. All other alternatively spliced transcripts were rare. Consensus and alternatively spliced transcripts were induced by lipopolysaccharide in synovial fibroblasts and PBLs. In transfected cells, the proteins encoded by all highly expressed splice forms were cytoplasmic. In contrast, native pyrin was predominantly nuclear in synovial fibroblasts, neutrophils, and dendritic cells, but was cytoplasmic in monocytes.

Conclusion

Several MEFV transcripts are expressed and inducible in synovial fibroblasts. A prominent isoform lacks the C‐terminal domain that contains the majority of mutations found in patients with FMF. While recombinant forms of all major pyrin isoforms are cytoplasmic, native pyrin is nuclear in several cell types. Thus, mechanisms in addition to splicing patterns must control pyrin's subcellular distribution.
Production of endogenous antibiotics in articular cartilage
Authors: Varoga Deike , Pufe Thomas , Harder Jürgen , Meyer‐Hoffert Ulf , Mentlein Rolf , Schröder Jens‐Michael , Petersen Wolf J. , Tillmann Bernhard N. , Proksch Ehrhardt , Goldring Mary B. , Paulsen Friedrich P.
Published: November 2004

Objective

Defensins are broad‐spectrum antimicrobial peptides that are components of innate immunity. To date, only epithelial surfaces and blood cells have been shown to produce these cationic peptides in bactericidal concentrations when challenged with microorganisms or inflammatory cytokines. Infections caused by gram‐negative pathogens occur only infrequently in association with joint surgery. The present study was undertaken to investigate whether this may be explained by intraarticular production of gram‐negative–specialized antimicrobial peptides.

Methods

Healthy articular cartilage and cultured T/C‐28a2 chondrocytes were assessed, by reverse transcriptase–polymerase chain reaction (RT‐PCR) and immunohistochemistry, for expression of various antimicrobial peptides. The expression of human β‐defensin 2 (HBD‐2) was studied in cultured chondrocytes after exposure to bacterial supernatants and proinflammatory cytokines and was assayed by real‐time RT‐PCR and immunoblot analysis. A septic arthritis mouse model was used to investigate the regulation of the murine homolog of HBD‐2 in articular cartilage after bacterial inoculation.

Results

Healthy articular cartilage and T/C‐28a2 chondrocytes were able to produce different antimicrobial peptides. After exposure to gram‐negative bacteria and proinflammatory cytokines, expression of cartilage‐derived HBD‐2 strongly increased. Immunoblot analysis revealed up‐regulation of the gram‐negative–specialized HBD‐2 in microbicidal doses. Immunohistochemistry analysis revealed induction of the murine homolog of HBD‐2 in vivo after intraarticular injection of bacteria.

Conclusion

This study demonstrated a previously unrecognized function of human chondrocytes. In addition to its biomechanical properties, articular cartilage has the ability to produce antimicrobial substances when challenged with microorganisms. The expression of HBD‐2 in microbicidal doses suggests that antimicrobial peptides may contribute to host defense mechanisms in articular joints.
Histologic analysis of renal leukocyte infiltration in antineutrophil cytoplasmic antibody–associated vasculitis: Importance of monocyte and neutrophil infiltration in tissue damage
Authors: Weidner Sven , Carl Marina , Riess Regine , Rupprecht Harald D.
Published: November 2004

Objective

The histopathologic lesions in antineutrophil cytoplasmic antibody (ANCA)–associated vasculitis (AAV) have been studied extensively, but the exact composition of the cellular infiltrate is unclear. We undertook this study to analyze renal leukocyte infiltration and the cellular distribution within glomeruli and interstitium in 65 renal biopsy samples obtained from patients newly diagnosed as having AAV.

Methods

Renal cellular tissue infiltration was assessed with an immunoperoxidase method. Furthermore, the infiltrating cell types were correlated with clinical and histopathologic data.

Results

The predominant interstitial infiltrating cells were T lymphocytes, while monocytes and, to a lesser extent, granulocytes constituted the dominant infiltrating cell types in glomeruli. Interestingly, lymphocyte infiltration was predominantly periglomerular, especially around glomeruli with sclerosis or heavy crescent formation, while interstitial monocyte and neutrophil infiltration was diffusely distributed over the interstitial tissue. A significant correlation was found for the glomerular infiltration of CD68‐positive macrophages with the presence of glomerular necrosis as well as with the number of glomeruli with crescents (P < 0.0001 and P = 0.005, respectively). No correlation was found for interstitial fibrosis with the infiltration of any leukocyte subset. Furthermore, a significant correlation was found for the interstitial as well as for the glomerular infiltration of CD68‐positive macrophages with serum creatinine concentration at the time of biopsy (P = 0.001 and P = 0.006, respectively).

Conclusion

These data underscore a major role of monocytes in addition to neutrophils in the tissue damage of AAV.
Increased susceptibility to rheumatoid arthritis in Koreans heterozygous for HLA–DRB1*0405 and *0901
Authors: Lee Hye‐Soon , Lee Kyung Wha , Song Gwan Gyu , Kim Hyun‐Ah , Kim Shin‐Yoon , Bae Sang‐Cheol
Published: November 2004

Objective

To investigate the association of susceptibility and protective HLA–DRB1 alleles with rheumatoid arthritis (RA) and its clinical markers in an Asian population.

Methods

All RA patients (n = 574) and control subjects (n = 392) were Korean. HLA–DRB1 typing and further subtyping of all alleles was performed by polymerase chain reaction, sequence‐specific oligonucleotide probe hybridization, and direct DNA sequencing analysis. We used a relative predispositional effects (RPEs) method and a false discovery rate correction method for multiple comparisons.

Results

The DRB1*0405 and *0901 alleles showed the most significant associations with RA (P = 7.83 × 10−24, odds ratio [OR] 4.40 [95% confidence interval (95% CI) 3.24–5.99], and P = 3.76 × 10−9, OR 2.47 [95% CI 1.82–3.36], respectively). The RPEs test showed that the DRB1*0401 and *0410 alleles conferred susceptibility and that the DRB1*0701, *0802, *1301, *1302, *1403, and *1405 alleles showed significant protective effects. Susceptibility and protective alleles both showed a pattern consistent with additive genetic effects, and each influenced RA independently of the other. The compound heterozygote DRB1*0405/*0901 was associated with the highest risk of RA (corrected P = 1.81 × 10−11, OR 58.2 [95% CI 7.95–425.70]). The mean age at disease onset was ∼4 years earlier or was 3 years earlier, respectively, in patients with at least 1 copy of the DRB1*0405 or the DRB1*0901 allele. Radiographic changes (stages II–IV) were more frequent in patients with at least 1 copy of DRB1*0405 (P = 0.032, 92.6% versus 84.3%, OR 2.33 [95% CI 1.24–4.39]).

Conclusion

The DRB1*0405/*0901 heterozygote has the strongest association with RA, suggesting that this heterozygote enhances the susceptibility to RA in Koreans.
Increased prevalence of squamous intraepithelial lesions in systemic lupus erythematosus: Association with human papillomavirus infection
Authors: Tam Lai‐Shan , Chan Alice Y. K. , Chan Paul K. S. , Chang Alexander R. , Li Edmund K.
Published: November 2004

Objective

To compare the prevalence of abnormal Pap smears in patients with systemic lupus erythematosus (SLE) with that in a large group of healthy controls, and to determine whether SLE itself is an independent risk factor. The association of human papillomavirus (HPV) infection and the use of immunosuppressive agents with abnormal Pap smears in SLE was also assessed.

Methods

Eighty‐five SLE patients participated in this cross‐sectional study. A sample of cervical cells was collected from each patient for routine cytologic examination. HPV was typed by restriction and sequencing analysis. A structured questionnaire was administered to the subjects to ascertain the possible behavioral and biologic risk factors associated with cervical atypia. Data on 2,080 healthy female subjects were retrieved for comparison.

Results

The mean (±SD) age of SLE patients and controls was 42 ± 9 years and 44 ± 10 years, respectively. The prevalence of abnormal Pap smears was significantly increased in SLE patients compared with controls (16.5% versus 5.7%). The prevalence of squamous intraepithelial lesions was increased ∼6‐fold in SLE patients (11.8%) compared with controls (2.0%). SLE itself remained an independent risk factor for abnormal Pap smears (odds ratio 3.5, 95% confidence interval 1.8–6.9). The overall prevalence of HPV infection in SLE patients and controls was 11.8% and 7.3%, respectively. However, 10.6% of SLE patients were infected with at least 1 high‐risk type of HPV, compared with 4.2% of controls. Multiple infections were also more common in SLE patients than in controls (4.7% versus 1.1%). There were no significant differences in the use of immunosuppressive agents between SLE patients with normal Pap smears and those with abnormal Pap smears.

Conclusion

Abnormal Pap smears were more common among SLE patients than controls, even after adjusting for HPV status. SLE‐associated immunosuppression increases susceptibility to high‐risk HPV infection and multiple HPV infections. The use of immunosuppressant agents was not associated with abnormal Pap smears.
Antiarthritic effect of bee venom: Inhibition of inflammation mediator generation by suppression of NF‐κB through interaction with the p50 subunit
Authors: Park Hye Ji , Lee Seong Ho , Son Dong Ju , Oh Ki Wan , Kim Ki Hyun , Song Ho Sueb , Kim Goon Joung , Oh Goo Taeg , Yoon Do Young , Hong Jin Tae
Published: November 2004

Objective

To investigate the molecular mechanisms of the antiarthritic effects of bee venom (BV) and melittin (a major component of BV) in a murine macrophage cell line (Raw 264.7) and in synoviocytes obtained from patients with rheumatoid arthritis.

Methods

We evaluated the antiarthritic effects of BV in a rat model of carrageenan‐induced acute edema in the paw and in a rat model of chronic adjuvant‐induced arthritis. The inhibitory effects of BV and melittin on inflammatory gene expression were measured by Western blotting, and the generation of prostaglandin E2 (PGE2) and nitric oxide (NO) and the intracellular calcium level were assayed. NF‐κB DNA binding and transcriptional activity were determined by gel mobility shift assay or by luciferase assay. Direct binding of BV and melittin to the p50 subunit of NF‐κB was determined with a surface plasmon resonance analyzer.

Results

BV (0.8 and 1.6 μg/kg) reduced the effects of carrageenan‐ and adjuvant‐induced arthritis. This reducing effect was consistent with the inhibitory effects of BV (0.5, 1, and 5 μg/ml) and melittin (5 and 10 μg/ml) on lipopolysaccharide (LPS; 1 μg/ml)–induced expression of cyclooxygenase 2, cytosolic phospholipase A2, inducible NO synthase, generation of PGE2 and NO, and the intracellular calcium level. BV and melittin prevented LPS‐induced transcriptional and DNA binding activity of NF‐κB via the inhibition of IκB release and p50 translocation. BV (affinity [Kd] = 4.6 × 10−6M) and melittin (Kd = 1.2 × 10−8M) bound directly to p50.

Conclusion

Target inactivation of NF‐κB by directly binding to the p50 subunit is an important mechanism of the antiarthritic effects of BV.
Cardiovascular risk factors in women with and without rheumatoid arthritis
Authors: Solomon Daniel H. , Curhan Gary C. , Rimm Eric B. , Cannuscio Carolyn C. , Karlson Elizabeth W.
Published: November 2004

Objective

The risk of cardiovascular disease (CVD) is increased in patients with rheumatoid arthritis (RA). The objective of this study was to examine the distribution of known CVD risk factors and biomarkers of CVD in women with and without RA.

Methods

This study included two components: an examination of clinical CVD risk factors among women participating in the Nurses' Health Study, a prospective longitudinal cohort, and an analysis of CVD biomarkers among a subgroup of women from this cohort who provided a blood specimen in 1989 (biospecimen cohort). Data regarding clinical risk factors for CVD were collected in 1990 by mailed questionnaire. The diagnosis of RA was confirmed through a structured medical record abstraction. We compared clinical risk factors for CVD and biomarkers of CVD between women with and without RA, adjusting for age, body mass index (BMI), smoking status, and menopause status.

Results

Women with RA (n = 287) were significantly more likely than women without RA (n = 87,019) to report no alcohol use (48.2% versus 39.4%) and past cigarette smoking (47.8% versus 38.0%). No significant differences between these groups were observed for current smoker status, BMI, regular aspirin use, diabetes, hypertension, physical activity, and family history of early myocardial infarction. In the biospecimen cohort (69 RA cases and 491 controls), the levels of several inflammatory biomarkers linked to CVD were significantly elevated in women with RA, including CRP, fibrinogen, sICAM‐1, sTNFRI, sTNFRII, and osteoprotegerin. Levels of total cholesterol, low‐density lipoprotein, triglycerides, apolipoprotein B, and Lp(a) were similar between groups. Levels of homocysteine were similar, but vitamin B12 was significantly higher among women with RA than among the controls.

Conclusion

In women participating in the Nurses' Health Study, most traditional CVD risk factors were similar between those who had RA and those who did not. However, as expected, biomarkers of inflammation associated with CVD were generally elevated in women with RA.
First reported pediatric case of systemic lupus erythematosus associated with prolactinoma
Authors: Reuman Peter D.
Published: November 2004

There is much interest in the possibility that prolactin influences disease activity in systemic lupus erythematosus (SLE). We present the first reported pediatric case of prolactinoma associated with SLE, in a 13‐year‐old white female. The diagnosis of SLE was based on the presence of arthritis, antinuclear antibodies, and double‐stranded DNA, and a chest radiograph showing pleural fluid. The diagnosis of pituitary prolactinoma was based on the histologic features and the presence of amenorrhea, galactorrhea, and an elevated serum prolactin level. Neurosurgical resection and medical therapy with bromocriptine mesylate were independently associated with decreased prolactin levels, loss of arthritis, and reduced levels of inflammatory mediators.
Schadensanalysen an Stahlbeton‐ und Spannbetonbrücken unter Einsatz eines Fuzzy‐Expertensystems
Authors: Lücken Theda
Published: November 2004

Es wird eine Vorgehensweise zur Analyse und Bewertung von Schäden an Stahlbeton‐ und Spannbetonbrücken vorgestellt. Sie umfaßt die Teilschritte Auswertung von Untersuchungsergebnissen, Schadensdiagnose, Schadensentwicklungsprognosen und Schadensbewertung. Besonderer Wert wird dabei auf die Berücksichtigung von Unschärfen in sprachlichen Ausdrücken, Entscheidungsvorgängen und unvollständigen Informationen gelegt, die mit Hilfe der Fuzzy‐Logik erfaßt werden. Die abgeleitete Vorgehensweise wird durch ein Fuzzy‐Expertensystem abgebildet. Es dient als Hilfsmittel für praktische Schadensanalysen.
Neue Mischbauweise mit Interner Vorspannung ohne Verbund: Pilotprojekt Mühlenbergbrücke
Authors: Haveresch Karlheinz
Published: November 2004

Spannbetonbrücken mit Externer Vorspannung haben eine besonders hohe Qualität. Sie sind deshalb für den Bauherrn sehr attraktiv. Die Anwendbarkeit dieser Bauweise kann aber bei sehr schlanken oder gekrümmten Brückenüberbauten eingeschränkt sein. Der folgende Beitrag stellt eine neue Variante der Mischbauweise vor, die die Einsatzmöglichkeiten der Externen Vorspannung wesentlich erweitern kann. Sie kann darüber hinaus auch erhebliche wirtschaftliche und bauverfahrenstechnische Vorteile gegenüber den bisher gültigen Bauweisen haben. Am Beispiel des Pilotprojektes Mühlenbergbrücke werden statisch‐konstruktive Eigenschaften der neuen Mischbauweise dargestellt.
Rückbau und Neubau der Kepplerbrücke in Rottenburg am Neckar
Authors: Braun Hansjörg , Hofmann Isabell
Published: November 2004

Die aus den Nachkriegsjahren stammende alte Kepplerbrücke in Rottenburg am Neckar wies gravierende Schäden auf. Eine Sanierung erwies sich als unwirtschaftlich und bereichsweise wegen Unzugänglichkeit sogar nicht möglich. Aus Überlegungen zu städtebaulichen Aspekten, Hochwasserschutz, Bauzeit, Bauablauf und Unterhaltungsfreundlichkeit entschied sich der Stadtrat für eine bewußt schlanke und elegante Stahlverbundbrücke, die farblich gestaltet werden konnte. Der Neubau besteht aus zwei luftdicht verschweißten, im Werk vorgefertigten, gevouteten Stahlkästen mit obenliegender, schlaff bewehrter Betonfahrbahnplatte.
Efficient water removal in lipase‐catalyzed esterifications using a low‐boiling‐point azeotrope
Authors: Yan Youchun , Bornscheuer Uwe T. , Schmid Rolf D.
Published: November 2004

High conversions in lipase‐catalyzed syntheses of esters from free acyl donors and an alcohol requires efficient removal of water preferentially at temperatures compatible to enzyme activity. Using a lipase B from Candida antarctica (CAL‐B)‐mediated synthesis of sugar fatty‐acid esters, we show that a mixture of ethyl methylketone (EMK) and hexane (best ratio: 4:1, vo/vo) allows efficient removal of water generated during esterification. Azeotropic distillation of the solvent mixture (composition: 26% EMK, 55% hexane, 19% water) takes place at 59°C, which closely matches the optimum temperature reported for CAL‐B. Water is then removed from the azeotrope by membrane vapor permeation. In case of glucose stearate, 93% yield was achieved after 48 h using an equimolar ratio of glucose and stearic acid. CAL‐B could be reused for seven reaction cycles, with 86% residual activity after 14 d total reaction time at 59°C. A decrease in fatty‐acid chain length as well as increasing temperatures (75°C) resulted in lower conversions. In addition, immobilization of CAL‐B on a magnetic polypropylene carrier (EP 100) facilitated separation of the biocatalyst. © 2002 Wiley Periodicals, Inc. Biotechnol Bioeng 78: 31–34, 2002; DOI 10.1002/bit.10084
Validation of a model for process development and scale‐up of packed‐bed solid‐state bioreactors
Authors: Weber Frans J. , Oostra Jaap , Tramper Johannes , Rinzema Arjen
Published: November 2004

We have validated our previously described model for scale‐up of packed‐bed solid‐state fermenters (Weber et al., 1999) with experiments in an adiabatic 15‐dm3 packed‐bed reactor, using the fungi Coniothyrium minitans and Aspergillus oryzae. Effects of temperature on respiration, growth, and sporulation of the biocontrol fungus C. minitans on hemp impregnated with a liquid medium were determined in independent experiments, and the first two effects were translated into a kinetic model, which was incorporated in the material and energy balances of the packed‐bed model. Predicted temperatures corresponded well with experimental results. As predicted, large amounts of water were lost due to evaporative cooling. With hemp as support no shrinkage was observed, and temperatures could be adequately controlled, both with C. minitans and A. oryzae. In experiments with grains, strong shrinkage of the grains was expected and observed. Nevertheless, cultivation of C. minitans on oats succeeded because this fungus did not form a tight hyphal network between the grains. However, cultivation of A. oryzae failed because shrinkage combined with the strong hyphal network formed by this fungus resulted in channeling, local overheating of the bed, and very inhomogeneous growth of the fungus. For cultivation of C. minitans on oats and for cultivation of A. oryzae on wheat and hemp, no kinetic models were available. Nevertheless, the enthalpy and water balances gave accurate temperature predictions when online measurements of oxygen consumption were used as input. The current model can be improved by incorporation of (1) gas‐solids water and heat transfer kinetics to account for deviations from equilibrium observed with fast‐growing fungi such as A. oryzae, and (2) the dynamic response of the fungus to changes in temperature, which were neglected in the isothermal kinetic experiments. © 2002 John Wiley & Sons, Inc. Biotechnol Bioeng 77: 381–393, 2002; DOI 10.1002/bit.10087
Chemometric evaluation of on‐line high‐pressure liquid chromatography in mammalian cell cultures: Analysis of amino acids and glucose
Authors: Larson Tina M. , Gawlitzek Martin , Evans Heather , Albers Urs , Cacia Jerry
Published: November 2004

An on‐line high‐pressure liquid chromatography (HPLC) system capable of measuring amino acids and carbohydrates was used to study metabolism in mammalian cell culture systems. The HPLC method utilized anion‐exchange chromatography followed by integrated pulsed amperometric detection. The method is capable of measuring 19 amino acids plus glucose with a complete method time of 65 min. In actual cell cultures, the method was shown to be useful for monitoring 17 amino acids plus glucose. The two amino acids that were not accurately monitored were arginine and lysine, possibly due to their elution near the void volume of the column. The HPLC system was used to study variability in metabolism across different cell culture processes, as well as the effect of glucose and glutamine limitation on a single cell culture process. Chemometric analysis was used to draw statistically meaningful conclusions from the highly correlated, multivariate data set that resulted from these experiments. Using chemometrics, variation between processes was linked to differences in uptake rates of seven amino acids. Similarly, lactate concentration, cell density, and aspartate uptake rate were linked to glucose and glutamine limitation. The effect of nutrient limitation on glutamate, alanine, and ammonium was also considered. © 2002 John Wiley & Sons, Inc. Biotechnol Bioeng 77: 553–563, 2002; DOI 10.1002/bit.10116
Numerical simulation for electrochemical cultivation of iron oxidizing bacteria
Authors: Matsumoto Norio , Yoshinaga Hisao , Ohmura Naoya , Ando Akikazu , Saiki Hiroshi
Published: November 2004

A numerical simulation model was constructed for electrochemical cultivation of iron oxidizing bacterium, Thiobacillus ferrooxidans, based on Monod's dual limitation equation. In this model, two limiting factors were examined, low supply of Fe(II) ion and dissolved oxygen, from empirical viewpoints. The simulation model was constructed taking into consideration the energy balance based on the amount of the electronic flow from the electrode to bacteria via an iron ion, and then to oxygen. The model consisted of a logarithmic bacterial growth phase during the first three days, followed by a plateau and growth limitation thereafter. The predicted results were in agreement with the actual growth under electrochemical cultivation. It was predicted the growth limiting factor would be changed from insufficient supply of Fe(II) ions to that of oxygen by decreasing the value of oxygen transfer constant K, which correlated with the aeration rate. The optimum aeration rate was determined for the ideal electrochemical cultivation. The algorithm described here can be used in any electrochemical cultivation by modifying the parameters for each system. © 2002 Wiley Periodicals, Inc. Biotechnol Bioeng 78: 17–23, 2002; DOI 10.1002/bit.10173
Quantitative analyses of anaerobic wastewater treatment processes: Identifiability and parameter estimation
Authors: Noykova Nelly , Müller Thorsten G. , Gyllenberg Mats , Timmer Jens
Published: November 2004

We investigated the problem of identifying the parameters of a nonlinear fifth order model describing the population dynamics of two main bacterial groups in an anaerobic wastewater treatment process. In addition to addressing problems concerning structural and practical identifiability, we also analyzed how mathematical descriptions of bacterial population dynamics can model real data. Using three data sets recorded under different experimental conditions, we estimated important biochemical parameters and demonstrated that our model could describe the data successfully. Parameters, which are simultaneously determined using information from all three experiments, have more reliable estimates. We conclude that, after appropriate estimation, this model can be used for optimization and the control of continuous processes. © 2002 Wiley Periodicals, Inc. Biotechnol Bioeng 78: 89–103, 2002; DOI 10.1002/bit.10179
Enhancement of shikonin production in single‐ and two‐phase suspension cultures of Lithospermum erythrorhizon cells using low‐energy ultrasound
Authors: Lin Lidong , Wu Jianyong
Published: November 2004

This work demonstrates the use of low‐energy ultrasound (US) to enhance secondary metabolite production in plant cell cultures. Suspension culture of Lithospermum erythrorhizon cells was exposed to low‐power US (power density ≤113.9 mW/cm3) for short periods (1–8 min). The US exposure significantly stimulated the shikonin biosynthesis of the cells, and at certain US doses, increased the volumetric shikonin yield by about 60%–70%. Meanwhile, the shikonin excreted from the cells was increased from 20% to 65%–70%, due partially to an increase in the cell membrane permeability by sonication. With combined use of US treatment and in situ product extraction by an organic solvent, or the two‐phase culture, the volumetric shikonin yield was increased more than two‐ to threefold. Increasing in the number of US exposures during the culture process usually resulted in negative effects on shikonin yield but slight stimulation of shikonin excretion. US at relatively high energy levels caused slight cell growth depression (maximum 9% decrease in dry cell weight). Two key enzymes for the secondary metabolite biosynthesis of cells, phenylalanine ammonia lyase and p‐hydroxybenzoic acid geranyltransferase, were found to be stimulated by the US. The US stimulation of secondary metabolite biosynthesis was attributed to the metabolic activity of cells activated by US, and more specifically, the defense responses of plant cells to the mechanical stress of US irradiation. © 2002 Wiley Periodicals, Inc. Biotechnol Bioeng 78: 81–88, 2002; DOI 10.1002/bit.10180
Screening for improved cell performance: Selection of subclones with altered production kinetics or improved stability by cell sorting
Authors: Böhm Ernst , Voglauer Regina , Steinfellner Willi , Kunert Renate , Borth Nicole , Katinger Hermann
Published: November 2004

One of the major problems in the biotechnology industry is the selection of cell lines well suited for production of biopharmaceutical proteins. Usually, the most important selection criterion is the cell specific production rate. Nevertheless, a good producer cell line should have a number of additional advantageous properties, which allow the cell line to perform well in the type of bioreactor chosen for the process. However, the time and work required to select for high production rates as well as the lack of methods to specifically select for other cellular properties, usually prevents researchers from including such criteria into their screening program.

With the Single Cell Secretion Assay it is possible to measure the specific production rates of individual cells by catching secreted product in an artificial matrix applied to the cell surface. Flow cytometric cell sorting then allows selection of rare cells with high production rates, which occur at frequencies as low as 10−6. By combining this method with culture conditions that bring out a desired cellular property, we were able to isolate subclones with similar production rates, but improved performance from a recombinant Chinese hamster ovary cell line producing a human monoclonal antibody. The two desired cellular properties screened for were a non‐growth associated production kinetic and improved stability in the absence of selective pressure. © 2004 Wiley Periodicals, Inc.
Enzymatic resolution for the preparation of enantiomerically enriched D‐β‐heterocyclic alanine derivatives using Escherichia coli aromatic L‐amino acid transaminase
Authors: Cho Byung‐Kwan , Park Hyung‐Yeon , Seo Joo‐Hyun , Kinnera Koteshwar , Lee Bon‐Su , Kim Byung‐Gee
Published: November 2004

An enzymatic resolution was carried out for the preparation of enriched β‐heterocyclic D‐alanine derivatives using Escherichia coli aromatic L‐amino acid transaminase. The excess of pyrazole, imidazole, or 1,2,4‐triazole reacted with methyl‐2‐acetamidoacrylate in acetonitrile in the presence of potassium carbonate at 60°C, directly leading to make the potassium salt of the corresponding N‐acetyl‐β‐heterocyclic alanine derivatives. After the acidic deprotection of the N‐acetyl group, 10 mM of racemic pyrazolylalanine, triazolylalanine, and imidazolylalanine were resolved to D‐pyrazolylalanine, D‐triazolylalanine, and D‐imidazolylalanine with 46% (85% ee), 42% (72% ee), and 48% (95% ee) conversion yield in 18 h, respectively, using E. coli aromatic L‐amino acid transaminase (EC 2.6.1.5). Although the three β‐heterocyclic L‐alanine derivatives have similar molecular structures, they showed different reaction rates and enantioselectivities. The relative reactivities of the transaminase toward the β‐heterocyclic L‐alanine derivatives could be explained by the relationship between the substrate binding energy (E, kcal/mol) to the enzyme active site and the distance (δ, Å) from the nitrogen of α‐amino group of the substrates to the C4′ carbon of PLP‐Lys258 Schiff base. As the ratio of the substrate binding energy (E) to the distance (δ) becomes indicative value of kcat/KM of the enzyme to the substrate, the relative reactivities of the β‐heterocyclic L‐alanine derivatives were successfully correlated with E/δ, and the relationship was confirmed by our experiments. © 2004 Wiley Periodicals, Inc.
The effect of environmental innovations on employment changes: an econometric analysis
Authors: Rennings Klaus , Ziegler Andreas , Zwick Thomas
Published: November 2004

This paper examines the determinants of employment changes due to an environmental innovation of an establishment. The data stem from telephone surveys in five European countries. 1594 interviews have been realized with environmentally innovative establishments representing the European industry and service sector. Based on results of discrete choice models, we show that if the most important environmental innovation is a product or service innovation it has a significantly positive effect on the probability of an increase in employment compared with the probability of no noticeable change. In contrast, if the most important environmental innovation is an end‐of‐pipe innovation it has a significantly positive influence on employment decrease. Methodologically, we consider the multinomial logit model and several multinomial probit models. We find that the estimates of the parameters of the explanatory variables are very similar in the different approaches. Copyright © 2004 John Wiley & Sons, Ltd and ERP Environment.
Integrating Input from Multiple Signals: The VirA/VirG Two‐Component System of Agrobacterium tumefaciens
Authors: Mukhopadhyay Aindrila , Gao Rong , Lynn David G.
Published: November 2004

Bacteria, fungi, and plants exploit histidine sensor kinase/response regulators to mobilize complex responses to inputs as diverse as environmental stimuli and hormonal regulation. More than 50 such two‐component systems are found in many organisms, yet the mechanisms of signal perception, phosphotransfer regulation, and even the nature of the activating signals remain poorly defined. Here we resolve each phosphate transfer event in vivo for the Agrobacterium tumefaciens virulence two‐component system VirA/VirG. The input signals for this system are known, and the complex autocatalytic regulation of the signaling components has been removed. Two separate and independent phosphotransfer events are resolved, an initial ATP→sensorHis∼PO4→receiver∼PO4, that may be activated by xenognostic sugar/low pH, and a subsequent ATP→His∼PO4→VirG∼PO4 that requires xenognostic phenol activation. The identification of these separate pathways places biochemical limits on the regulated steps in this two‐component signal transduction module and further extends the model of how a single sensor is able to integrate multiple input stimuli.
A New Family of Synthetic Diterpenes that Regulates Cytokine Synthesis by Inhibiting IκBα Phosphorylation
Authors: Chao Ta‐Hsiang , Lam Thanh , Vong Binh G. , Través Paqui G. , Hortelano Sonsoles , Chowdhury Chinmay , Bahjat F. Rena , Lloyd G. Kenneth , Moldawer Lyle L. , Boscá Lisardo , Palladino Michael A. , Theodorakis Emmanuel A.
Published: November 2004

The synthesis and the biological evaluation of a new family diterpenes are presented. The synthetic studies were inspired by the structural framework of acanthoic acid (1) and yielded a family of compounds that were evaluated as anti‐inflammatory agents. Among them, compounds 2, 10, 12, and 16 exhibited a very low nonspecific cytotoxicity and inhibited the synthesis of TNF‐α with greater than 65 % efficacy at low micromolar concentrations. Cytokine‐specificity studies revealed that these compounds also inhibited the synthesis of the proinflammatory cytokines IL‐1β and IL‐6, while inhibition of IL‐1ra and IL‐8 synthesis was marginal and only occurred at high concentrations. Further studies, through EMSA and Western blot analyses, indicated that these compounds decreased the extent of phosphorylation of IκBα; this suggests that they exert their anti‐inflammatory profile by inhibiting NF‐κB‐mediated cytokine synthesis. These findings imply that these diterpenes represent promising leads for the development of novel anti‐inflammatory agents.
Liquid Oxygenation Improvement by Interaction of Bubbles and Vibration Fields
Authors: Grinis L. , Kholmer V. , Korin E.
Published: November 2004

Gas bubble motion characteristics and bubble size are important factors in various technological processes involving the interaction between liquid and gaseous systems. The present work studies the effect of vibration fields on the characteristics of bubble motion and bubble size. Bubble retention time in the liquid (rise velocity) and bubble mean diameter were chosen as main parameters effecting the oxygen mass transfer rate. A device for mechanical vibration of the aerated liquid was used. The influence of the device design parameters on the chosen bubble parameters is studied experimentally and discussed in this work. The results obtained show the possibility of controlling bubble retention time and bubble size by employing vibration fields. Thus, by applying rather simple techniques, one can considerably improve the process of liquid oxygenation.
Determination of Drying Characteristics and Effective Diffusivity for Sugar Cubes
Authors: Akosman C.
Published: November 2004

In this study, the drying characteristics of sugar cubes have been investigated. Drying experiments with sugar cubes were conducted in a laboratory‐type tray dryer at temperatures ranging from 45 to 95 °C and different air velocities (0.43, 0.56, and 0.7 m/s). Drying rates increased with the increase in temperature and air velocity. At high temperatures, the moisture content of the solid reached equilibrium moisture value in short time periods. Experimental data were analyzed by using the analytical solution of the unsteady‐state diffusion equation to determine the effective diffusivity in sugar cubes.
Comprehensive Characterization of a Sooting Laminar Methane‐Diffusion Flame Using Different Laser Techniques
Authors: Seeger T. , Egermann J. , Dankers S. , Beyrau F. , Leipertz A.
Published: November 2004

The potential of a combination of optical diagnostic tools is demonstrated for the characterization of a sooting laminar methane diffusion flame. Time‐resolved laser‐induced incandescence, Rotational CARS spectroscopy, spontaneous Raman scattering, and the laser‐induced fluorescence technique have been applied to measure the soot primary particle size and volume concentrations and the concentration of species in the surrounding gas.
A New Comprehensive Model and Simulation Package for Fluidized Bed Spray Granulation Processes
Authors: Ihlow M. , Drechsler J. , Peglow M. , Henneberg M. , Mörl L.
Published: November 2004

The model introduced in this paper makes it possible to calculate the expected product and bed material particle size distribution, as well as the dynamic behavior of process state variables. It was integrated in the developed software package FBSim and it could be shown that even a complex process like the fluidized bed spray granulation can be simulated in its dynamic behavior, if existing models are extended and coupled. The implemented model achieves a coupled solution of the population balance and heat and mass transfer equations.
Rational Catalyst Design of Methanol Synthesis Catalysts
Authors: Kurtz M. , Bauer N. , Wilmer H. , Hinrichsen O. , Muhler M.
Published: November 2004

The Cu/ZnO/Al2O3 catalyst prepared by the co‐precipitation method is employed in industrial large‐scale methanol synthesis. Although intensive research has already been carried out on this catalyst system, several attempts are still being made to improve it. The knowledge‐based approach provides the basis for a rational improvement of the well‐established catalyst systems for methanol synthesis.
Decision pathway modeling
Authors: Myles Anthony J. , Brown Steven D.
Published: November 2004

Pattern recognition is playing an increasingly important role in chemical and biochemical data analysis. Many of these pattern recognition applications call for the discrimination of more than two classes of objects. Decision pathway modeling is proposed as a novel pattern recognition technique for multigroup classification. Decision pathway modeling decomposes the multigroup classification problem into simpler binary discrimination tasks, which are then reassembled into a single hierarchical architecture. To minimize effects of error propagation through the hierarchical architecture, dynamic pathway selection is proposed to adaptively direct the classification of new samples. Decision pathway modeling is compared against generalized multigroup and coupled binary discriminant techniques in terms of classification accuracy. The benefit of decision pathway modeling is shown to arise from the hierarchical decomposition and by the dynamic selection of classification pathways. Copyright © 2004 John Wiley & Sons, Ltd.
Active learning support vector machines for optimal sample selection in classification
Authors: Zomer Simeone , Del Nogal Sánchez Miguel , Brereton Richard G. , Pérez Pavón José L.
Published: November 2004

Labelling samples is a procedure that may result in significant delays particularly when dealing with larger datasets and/or when labelling implies prolonged analysis. In such cases a strategy that allows the construction of a reliable classifier on the basis of a minimal sized training set by labelling a minor fraction of samples can be of advantage. Support vector machines (SVMs) are ideal for such an approach because the classifier relies on only a small subset of samples, namely the support vectors, while being independent from the remaining ones that typically form the majority of the dataset. This paper describes a procedure where a SVM classifier is constructed with support vectors systematically retrieved from the pool of unlabelled samples. The procedure is termed ‘active’ because the algorithm interacts with the samples prior to their labelling rather than waiting passively for the input. The learning behaviour on simulated datasets is analysed and a practical application for the detection of hydrocarbons in soils using mass spectrometry is described. Results on simulations show that the active learning SVM performs optimally on datasets where the classes display an intermediate level of separation. On the real case study the classifier correctly assesses the membership of all samples in the original dataset by requiring for labelling around 14% of the data. Its subsequent application on a second dataset of analogous nature also provides perfect classification without further labelling, giving the same outcome as most classical techniques based on the entirely labelled original dataset. Copyright © 2004 John Wiley & Sons, Ltd.
‘Just teach us the skills please, we'll do the rest’: empowering ten‐year‐olds as active researchers
Authors: Kellett Mary , Forrest (aged ten) Ruth , Dent (aged ten) Naomi , Ward (aged ten) Simon
Published: November 2004

This paper discusses the outcomes of an initiative to empower ten‐year‐olds as active researchers. It debates some of the barriers that are commonly cited with regard to children of this age taking ownership of their own research agendas—power relations, competence, knowledge and skills—and challenges the status quo. It describes a study in which a group of ten‐year‐olds participated in a taught programme aimed at equipping them with the knowledge and skills to design their own research. This empowering process resulted in the children undertaking research projects of their own choosing, designed, carried out and reported entirely from their perspective. Reports from two of those projects are presented as part of this paper.
Reaktivsorption von L‐Phenylalanin durch kationentauscherimprägnierte Polymere (Gleichgewichte)
Authors: Kostova A. , Bart H.‐J.
Published: November 2004

No abstracts.
Hydrierung und Carbonylierung mit durch Ionenstrahlverfahren hergestellten mono‐ und bimetallischen Schalenkatalysatoren
Authors: Wolff S. , Wolf G. K. , Hagen J.
Published: November 2004

No abstracts.
Beeinflussung der Porenstruktur von Adsorbentien durch Abscheidung von Kohlenstoff und die Auswirkungen auf Adsorptionskapazität und ‐geschwindigkeit
Authors: Lange R. , Heschel W. , Wirling J.
Published: November 2004

No abstracts.
CFD‐Simulation der chemischen Absorption im Strahlwäscher
Authors: Loos T. , Mollekopf N.
Published: November 2004

No abstracts.
Demineralisierung von Braunkohle in Kombination mit der mechanisch/thermischen Entwässerung
Authors: Wild T. , Bergins C. , Strauß K.
Published: November 2004

No abstracts.
Theoretische und experimentelle Untersuchungen der Mischvorgänge in T‐förmigen Mikroreaktoren – Teil 2: Experimentelle Untersuchung des Strömungsmischens
Authors: Schlüter M. , Hoffmann M. , Räbiger N.
Published: November 2004

No abstracts.
Untersuchung des externen Stofftransports in einem Mikrostrukturreaktor durch Druckvariation
Authors: Kölbl A. , Pfeifer P. , Kraut M. , Schubert K. , Emig G. , Liauw M. A. , Fichtner M.
Published: November 2004

No abstracts.