bluuebunny/crossref_metadata_2025_split huggingface dataset:
Verstärkung der Melan‐Brücke über die Sieg bei St. Augustin
Authors: Goralski Claus , Eggemann Holger 
Published: December 2007

AbstractDie Brücke über die Sieg bei Menden/St. Augustin (Bonn) wurde 1929 nach Bauweise Melan gebaut. Der Bogen der Hauptöffnung ist oberhalb der Fahrbahn gespannt, die mittels Betonhängern an diesen angebunden ist. Nach diesem Prinzip wurden nur wenige Melan‐Bögen ausgeführt, ein weiterer z. B. in Arnau über die Elbe. Im Jahre 2006 sollte die Brücke nach DIN‐Fachbericht beurteilt und eingestuft werden. Der Aufsatz beschreibt den Bau und die Geschichte der Brücke sowie die Verstärkungsmaßnahme im Jahre 2007, welche aufgrund einer Überbeanspruchung der Hänger erforderlich wurde. Nur durch deren sofortige Verstärkung der überbeanspruchten Hänger konnte die Nutzung der Brücke durch den öffentlichen Nahverkehr und einen begrenzten Schwerverkehr sichergestellt werden. Zurzeit wird im Rahmen einer Wirtschaftlichkeitsstudie untersucht, ob durch weitere Verstärkungsmaßnahmen die Einschränkungen im Schwerverkehr aufgehoben werden können. Im Juni 2007 wurde die Brücke in die Denkmallisten der Städte St. Augustin und Troisdorf eingetragen. Herr Dr.‐Ing. Rüdiger Beutel, der federführend an Nachrechnung und Verstärkung der Brücke beteiligt war, verstarb völlig unerwartet im Juni 2007. Ihm ist dieser Beitrag gewidmet.
P450cam biocatalysis in surfactant‐stabilized two‐phase emulsions
Authors: Ryan Jessica D. , Clark Douglas S. 
Published: December 2007

AbstractCytochrome P450 monooxygenases (P450s) are powerful biocatalysts that have the ability to oxidize a broad range of substrates, often at non‐reactive carbon centers. However, incorporation of P450s into synthetic schemes has so far been limited to a few whole‐cell transformations. P450 substrates are often hydrophobic and have low water solubility, limiting the amount of product that can be produced. To help overcome this limitation, we have examined P450cam activity in two‐phase hexane/water emulsions with and without the anionic surfactant, bis(2‐ethylhexyl) sulfosuccinate sodium salt (AOT). Hydroxylation of camphor to hydroxycamphor by the three‐ component P450cam system was chosen as the model reaction, and regeneration of NADH was accomplished with yeast alcohol dehydrogenase (YADH). P450cam was activated in the surfactant‐free emulsions, and addition of AOT improved the activity even further, at least over the range of camphor concentrations for which initial rates were readily measurable in all media. The largest observed rate enhancement was 4.5‐fold. Nearly 50‐times more product was formed in the surfactant‐stabilized emulsions than was achieved in aqueous buffer, with total turnover numbers reaching 28,900 for P450cam and 11,800 for YADH. In the absence of surfactant, the two‐phase reaction appeared to be mass‐transfer limited, while inclusion of AOT alleviated transport limitations and/or afforded a larger interfacial area for P450 activation. The oxidation of hydroxycamphor to 2,5‐diketocamphane was also observed, owing to the large concentration of hydroxycamphor relative to camphor in the aqueous phase of the two‐phase emulsion. This competing reaction was accompanied by the uncoupled oxidation of NADH (i.e., NADH oxidation without formation of 2,5‐diketocamphane), which reduced the availability of NADH for camphor oxidation and further limited the yield of hydroxycamphor in the two‐phase emulsions. These results indicate that a surfactant‐stabilized two‐phase emulsion is a promising reaction medium for practical P450 biocatalysis, although its effectiveness for a given P450/substrate combination can depend on several factors, including competitive or sequential reactions, product inhibition, and NAD(P)H uncoupling. Biotechnol. Bioeng. 2008;99: 1311–1319. © 2007 Wiley Periodicals, Inc.
Characterization of the Peroxidase Activity of CYP119, a Thermostable P450 From Sulfolobus acidocaldarius
Authors: Rabe Kersten S. , Kiko Kathrin , Niemeyer Christof M. 
Published: December 2007

AbstractWe report the cloning, expression, and purification of CYP119, a thermostable enzyme previously thought to derive from Sulfolobus solfataricus. Sequence analysis suggested that, in contrast to the conclusions of earlier studies, the enzyme stems from the closely related Sulfolobus acidocaldarius, and we were indeed able to clone the gene from the genomic DNA of this organism. For the first time, we report here on the peroxidase activity of this enzyme and the optimization of the associated reaction parameters. The optimized reaction conditions were then applied to the biocatalytic epoxidation of styrene. The values obtained for kcat (78.2±20.6 min−1) and KM (9.2±4.3 mM) indicated an approximately 100‐fold increased catalytic activity over previously reported results.
Heterologous Expression And Genetic Engineering of the Phenalinolactone Biosynthetic Gene Cluster by Using Red/ET Recombineering
Authors: Binz Tina M. , Wenzel Silke C. , Schnell Hans‐Jörg , Bechthold Andreas , Müller Rolf 
Published: December 2007

AbstractThe heterologous expression of natural product biosynthetic pathways is of increasing interest in biotechnology and drug discovery. This approach enables the production of complex metabolites in more amenable host organisms and provides the basis for the generation of novel analogues through genetic engineering. Here we describe a straightforward strategy for the heterologous expression of the highly complex phenalinolactone biosynthetic pathway, which was recently cloned from Streptomyces sp. Tü6071. The biosynthetic gene cluster comprises at least 11 transcriptional units that harbor 35 genes, which together catalyze the assembly of structurally unique tricyclic terpene glycosides with antibacterial activity. By using Red/ET recombineering, the phenalinolactone pathway was reconstituted from two cosmids and heterologously expressed in several Streptomyces strains. The established expression system now provides a convenient platform for functional investigations of the biosynthetic genes and the generation of novel analogues, by genetic engineering of the pathway in Escherichia coli. Deletion of a modifying gene from the expression construct resulted in a novel, unglycosylated phenalinolactone derivative; this demonstrates the promise of this methodology.
Robust partial least squares regression: Part I, algorithmic developments
Authors: Kruger Uwe , Zhou Yan , Wang Xun , Rooney David , Thompson Jillian 
Published: December 2007

AbstractThe work summarized in this paper presents the first part of a three‐paper series on robust partial least squares (RPLS) regression. Motivated by recent research activities in this area, this part provides a detailed algorithmic analysis of associated techniques, showing that existing work (i) may not represent a true robust formulation of partial least squares (PLS), (ii) may lead to convergence problems or (iii) may be insensitive to a certain type of outlier. On the basis of this analysis, Part I introduces a new conceptual RPLS algorithm that overcomes the deficiencies of existing work. The second part of this work details this new RPLS technique, compares its peformance with existing RPLS methods and provides an analysis on the computational efficiency and sensitivity of these algorithms. Whilst the first two parts of this work discuss algorithmic developments of RPLS, the final part concentrates on practical issues of RPLS implementations. This third part is devoted to practitioners of chemistry and chemical engineering covering a wide range of applications involving a calibration experiment, the analysis of recorded data from an industrial debutanizer process and data from a number of Raman spectroscopy experiments. Copyright © 2007 John Wiley & Sons, Ltd.
Robust partial least squares regression: Part II, new algorithm and benchmark studies
Authors: Kruger Uwe , Zhou Yan , Wang Xun , Rooney David , Thompson Jillian 
Published: December 2007

AbstractThis paper presents the second part of the work on robust partial least squares (RPLS) regression and develops a new RPLS algorithm based on the concept laid out in Part I. The paper also contrasts the new algorithm with existing work using two simulation examples. This comparison highlights (i) the impact of the flaws in existing RPLS work and (ii) the compromised sensitivity resulting from introducing simplifications to the determination of the Stahel–Donoho estimator (SDE). The paper finally presents an evaluation of the computational complexity of RPLS algorithms and examines the impact of the signal‐to‐noise ratio (SNR) upon the sensitivity of detecting outliers. The third part of this work will examine practical aspects of RPLS applications based on the analysis of experimental data. Copyright © 2007 John Wiley & Sons, Ltd.
Reduction of Lipophilicity at the Lipophilic Domain of RXR Agonists Enables Production of Subtype Preference: RXRα‐Preferential Agonist Possessing a Sulfonamide Moiety
Authors: Takamatsu Kayo , Takano Atsushi , Yakushiji Nobumasa , Morishita Ken‐ichi , Matsuura Nobuyasu , Makishima Makoto , Ali Hamed Ismail , Akaho Eiichi , Tai Akihiro , Sasaki Kenji , Kakuta Hiroki 
Published: December 2007

AbstractRetinoid X receptor agonists (RXR agonists, rexinoids) are interesting candidates for the treatment of cancers such as tamoxifen‐resistant breast cancer and taxol‐resistant lung cancer. However, well‐known RXR agonists possess a strong lipophilic character. In addition, although RXR has three subtypes, no subtype‐selective RXR agonists are known. Thus we aimed to produce less‐lipophilic and subtype‐selective RXR agonists. By designing sulfonamide‐type RXR agonists, 4‐[N‐methanesulfonyl‐N‐(5,5,8,8‐tetramethyl‐5,6,7,8‐tetrahydro‐2‐naphthyl)amino]benzoic acid (8 a) was found to prefer RXRα over RXRβ and RXRγ, although the potency is less than the potencies of well‐known RXR pan‐agonists. Moreover, our results suggest that the reduction of lipophilicity at the hydrophobic interaction region of RXR agonists enables production of RXR subtype preference. Our finding will be useful for the creation of more potent and less‐lipophilic subtype‐selective RXR agonists aimed at the reduction of undesirable side effects.
Cost analysis of the National Breast and Cervical Cancer Early Detection Program
Authors: Ekwueme Donatus U. , Gardner James G. , Subramanian Sujha , Tangka Florence K. , Bapat Bela , Richardson Lisa C. 
Published: December 2007

AbstractBACKGROUND.The National Breast and Cervical Cancer Early Detection Program (NBCCEDP) was established by the U.S. Congress in 1990. In recent years, there has been an emphasis on ascertaining the NBCCEDP's costs of delivering screening and diagnostic services to medically underserved, low‐income women. The objective of this report was to address 3 economic questions: What is the cost per woman served in the program, what is the cost per woman served by program component, and what is the cost per cancer detected through the program?METHODS.The authors developed a questionnaire to systematically collect activity‐based costs on screening for breast and cervical cancer from 9 participating programs. The questionnaire was developed based on well established methods of collecting cost data for program evaluation. Data were collected from July 2003 through June 2004.RESULTS.With in‐kind contributions, the cost of screening services to women in 9 programs was estimated at $555 per woman served. Without in‐kind contributions, this cost was $519. Among the program components, screening and coalitions/partnerships accounted for the highest and lowest cost per woman served, respectively. The median cost of screening a woman for breast cancer was $94, and the cost per breast cancer detected was $10,566. For cervical cancer, these costs were $56 and $13,340, respectively.CONCLUSIONS.Costs per woman served, screened, and cancers detected are needed for programs to accurately determine the resources required to reach and screen eligible women. With limited program resources, these cost estimates can provide useful information to assist programs in planning and implementing cost‐effective activities that could maximize the allocation of program resources. Cancer 2008. Published 2007 by the American Cancer Society
Biotic complexity of population dynamics
Authors: Sabelli Hector , Kovacevic Lazar 
Published: December 2007

AbstractChanges in population size of animal species (lynx, muskrat, beaver, salmon, and fox), show diversification, episodic patterns in recurrence plots, novelty, nonrandom complexity, and asymmetric statistical distribution. These features of creativity characterize bios, a nonstationary pattern generated by bipolar feedback and multi‐agent predator–prey simulations, absent in chaotic attractors. Population series show partial‐autocorrelation, and the time series of the differences between consecutive terms also showed nonrandom patterns, differentiating bios from noise. As biotic patterns are found in quantum, cosmological, meteorological, biological, and economic processes, we propose that bipolar feedback is a generic process that contributes to the evolutionary generation of complexity at multiple levels of organization. © 2007 Wiley Periodicals, Inc. Complexity, 2008.
Evolutionary learning of small networks
Authors: Filk Thomas , von Müller Albrecht 
Published: December 2007

AbstractResults are presented of a simulation that mimics an evolutionary learning process for small networks. Special features of these networks include a high recurrency, a transition function which decreases for large input activities, and the absence of tunable weights attached to the lines—the line is either there (weight 1) or absent (weight 0). It is remarkable that these simple systems already exhibit a complex learning behavior and a phenomenon of punctuated equilibrium in the evolutionary process. These findings should be of interest for both, the general understanding of evolutionary dynamics and, more specifically, the understanding of the role of recurrence in combination with nonmonotic response patterns for learning processes. © 2007 Wiley Periodicals, Inc. Complexity, 2008
TLR7 stimulation augments T effector‐mediated rejection of skin expressing neo‐self antigen in keratinocytes
Authors: Zhong Jie , Hadis Usriansyah , De Kluyver Rachel , Leggatt Graham R. , Fernando Germain J. P. , Frazer Ian H. 
Published: December 2007

AbstractImmunotherapy generally fails to induce tumour regression in spontaneously arising tumours. Failure is attributed to both tumour‐related factors and an ineffective immune response. As a model of tumour immunotherapy, without the confounding effects of potential tumour‐determined mechanisms of immune evasion, we studied the requirements for rejection of skin grafts expressing a neo‐self antigen in somatic cells and not in antigen‐presenting cells. When antigen expression was restricted to somatic cells, both CD4+ and CD8+ effector cells were required for graft rejection. Although freshly placed grafts were spontaneously rejected, healed grafts established under the cover of T cell depletion were not rejected even after T cell numbers recovered to a level where freshly placed grafts on the same animal were rejected, suggesting that healed skin grafts expressing a neo‐self antigen only in somatic cells could not be rejected by primed recipients with functional effector T cells. Local TLR7 ligation induced inflammatory responses and rejection of healed grafts exposed to the TLR agonist but did not induce rejection of untreated healed grafts on the same animal. Thus, local pro‐inflammatory signalling via TLR7 can promote effector T cell function against skin cells displaying their nominal antigen.
Functional inhibition related to structure of a highly potent insulin‐specific CD8 T cell clone using altered peptide ligands
Authors: Petrich de Marquesini Liliana G. , Moustakas Antonis K. , Thomas Ian J. , Wen Li , Papadopoulos George K. , Wong F. Susan 
Published: December 2007

AbstractInsulin‐reactive CD8 T cells are amongst the earliest islet‐infiltrating CD8 T cells in NOD mice. Cloned insulin B15–23‐reactive cells (designated G9C8), restricted by H‐2Kd, are highly diabetogenic. We used altered peptide ligands (APL) substituted at TCR contact sites, positions (p)6 and 8, to investigate G9C8 T cell function and correlated this with structure. Cytotoxicity and IFN‐γ production assays revealed that p6G and p8R could not be replaced by any naturally occurring amino acid without abrogating recognition and functional response by the G9C8 clone. When tested for antagonist activity with APL differing from the native peptide at either of these positions, the peptide variants, G6H and R8L showed the capacity to reduce the agonist response to the native peptide. The antagonist activity in cytotoxicity and IFN‐γ production assays can be correlated with conformational changes induced by different structures of the MHC‐peptide complexes, shown by molecular modeling. We conclude that p6 and p8 of the insulin B15–23 peptide are very important for TCR stimulation of this clone and no substitutions are tolerated at these positions in the peptide. This is important in considering the therapeutic use of peptides as APL that encompass both CD4 and CD8 epitopes of insulin.
Fine‐tuning CD4+ central memory T cell heterogeneity by strength of stimulation
Authors: Kalia Vandana , Sarkar Surojit , Ahmed Rafi 
Published: December 2007

AbstractThe memory T cell pool serves as a relatively long‐lived heterogeneous repository of antigen‐experienced T cells that "remember" previous encounters with antigen. While heterogeneity in the memory T cell pool is now well established, signals regulating the generation of this memory T cell heterogeneity are not fully understood. Two articles in this issue of the European Journal of Immunology highlight the importance of the strength of antigenic stimulation in regulating the generation of phenotypically and functionally distinct CD4+ T cell memory subsets. New insights are also provided into key molecular players that likely mediate differences in homeostatic and secondary expansion between the memory subsets.See accompanying articles: http://dx.doi.org/10.1002/eji200737611 and http://dx.doi.org/10.1002/eji200737852
Cover Picture: Expression of PI(4,5)P2‐binding proteins lowers the PI(4,5)P2 level and inhibits FcγRIIA‐mediated cell spreading and phagocytosis – Eur. J. Immunol. 1/2008
Authors: Szymańska Ewelina , Sobota Andrzej , Czuryło Edward , Kwiatkowska Katarzyna 
Published: December 2007

AbstractThe cover picture is a composite of images from Szymańska et al. (pp. 260–272) showing colocalisation of PIP5‐kinase Iα, but not PIP5‐kinase Iγ, with actin filaments and PI(4,5)P2 in filopodia and lamellipodia during FcγRIIA‐driven cell spreading (“frustrated phagocytosis”). Szymańska et al. show that expression of PI(4,5)P2‐binding domains in FcγRIIA‐treated cells decreases the high PI(4,5)P2 levels induced by FcγRIIA and also inhibits cell spreading and phagocytosis. This is a point worth bearing in mind as probes binding to PI(4,5)P2 are often used as tracers of PI(4,5)P2 location in cells – the tracers may ultimately alter the location of the molecules they are tracing! The authors suggest that the PI(4,5)P2‐binding domains compete with PIP5‐kinase Iα for PI(4,5)P2 binding, thereby reducing the association of PIP5‐kinase Iα with the plasma membrane, ultimately reducing PI(4,5)P2 generation.
Dinoflagellate cyst stratigraphy and palaeoenvironment of the marginal marine Middle and Upper Miocene of the eastern Campine area, northern Belgium (southern North Sea Basin)
Authors: Louwye Stephen , Laga Pieter 
Published: December 2007

AbstractA stratigraphical and palaeoenvironmental analysis with organic‐walled palynomorphs of the Bolderberg and Diest formations provides new insights in the depositional history during Miocene times at the southern border of the North Sea Basin. The Neogene transgression invaded Belgium from a north–northwestern direction and fully marine sediments were deposited in the northern part of Belgium. The age and the palaeoenvironment of the deposits at the very border of the southern North Sea Basin remained till a few decades ago incomplete. The recovered dinoflagellate cysts, acritarchs and green algae from the Bolderberg Formation in the Wijshagen Borehole indicate a marginal marine depositional environment during late Burdigalian and Langhian times in the eastern Campine area, in contrast to the deeper marine conditions prevailing to the north–northwest. The relative dating of the Bolderberg Formation confirms that maximum flooding occurred during Langhian to early Serravallian times. Deposition apparently took place during the Middle Miocene Climatic Optimum, and ended when the climatic deterioration set in at around 14 Ma. A hiatus spanning ca. 2 Ma separates the Middle Miocene Bolderberg Formation from the Upper Miocene Diest Formation in the eastern Campine area at the border of the North Sea Basin. Copyright © 2007 John Wiley & Sons, Ltd.
Quality of life in oral carcinoma: A 5‐year prospective study
Authors: Nordgren Mats , Hammerlid Eva , Bjordal Kristin , Ahlner‐Elmqvist Marianne , Boysen Morten , Jannert Magnus 
Published: December 2007

AbstractBackground.We conducted this prospective longitudinal multicenter study to evaluate the health‐related quality of life (HRQL) of patients with oral carcinoma at diagnosis, and after 1 and 5 years in relation to tumour location and treatment modality.Methods.One hundred twenty‐two patients (mean age, 61; 62% males) with oral carcinoma were evaluated with standardized HRQL questionnaires, the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core30 (EORTC QLQ‐C30) and the EORTC Head and Neck Cancer Module (EORTC QLQ‐H&N35).Results.Problems with teeth, dry mouth, and sticky saliva got worse between diagnosis and 5 years after diagnosis. Problems with dry mouth remained a problem between 1 and 5 years after diagnosis, except for the patients treated with surgery only. This group had fewer problems over time compared with patients receiving other treatment regimes. Survivors reported better HRQL than the nonsurvivors at diagnosis and at the 1‐year follow‐up. HRQL at diagnosis was associated with survival.Conclusions.HRQL at diagnosis for patients with oral carcinoma seems to be an important factor for the prognosis of both HRQL over time and survival. Treatment of oral carcinoma often results in long‐term side effects such as dry mouth, problems with teeth, and sticky saliva. © 2007 Wiley Periodicals, Inc. Head Neck, 2008
Semi‐structural models of advertising competition
Authors: Pinkse Joris , Slade Margaret 
Published: December 2007

AbstractWe propose a semi‐structural discrete‐choice model that can be used to estimate static or dynamic decision rules. It is particularly useful in strategic contexts when games involve a rich set of choices, when private information is correlated, and when one wants to uncover the effect of historic behavior (on, for example, prices, sales, and profits). We apply our discrete‐choice estimator to study decision rules for a dynamic game of price and advertising competition, and we evaluate the long‐run consequences of those rules. Copyright © 2007 John Wiley & Sons, Ltd.