bluuebunny/crossref_metadata_2025_split huggingface dataset:
Eicosanoids in insect immunity: Bacterial infection stimulates hemocytic phospholipase A2 activity in tobacco hornworms
Authors: Tunaz Hasan , Park Youngjin , Büyükgüzel Kemal , Bedick Jon C. , Nor Aliza A.R. , Stanley David W. 
Published: December 2002

AbstractIntracellular phospholipase A2 (PLA2) is responsible for releasing arachidonic acid from cellular phospholipids, and is thought to be the first step in eicosanoid biosynthesis. Intracellular PLA2s have been characterized in fat body and hemocytes from tobacco hornworms, Manduca sexta. Here we show that bacterial challenge stimulated increased PLA2 activity in isolated hemocyte preparations, relative to control hemocyte preparations that were challenged with water. The increased activity was detected as early as 15 s post‐challenge and lasted for at least 1 h. The increased activity depended on a minimum bacterial challenge dose, and was inhibited in reactions conducted in the presence of oleyoxyethylphosphorylcholine, a site‐specific PLA2 inhibitor. In independent experiments with serum prepared from whole hemolymph, we found no PLA2 activity was secreted into serum during the first 24 h following bacterial infection. We infer that a hemocytic intracellular PLA2 activity is increased immediately an infection is detected. The significance of this enzyme lies in its role in launching the biosynthesis of eicosanoids, which mediate cellular immune reactions to bacterial infection. Arch. Insect Biochem. Physiol. 52:1–6, 2003. © 2003 Wiley‐Liss, Inc.
Positive and negative modulation of Bombyx mori adenylate cyclase by 5‐phenyloxazoles: Identification of octopamine and tyramine receptor agonists
Authors: Khan Md. Anwar Arfien , Nakane Toshiya , Ohta Hiroto , Ozoe Yoshihisa 
Published: December 2002

AbstractNineteen 5‐phenyloxazoles (5POs) were examined for their ability to modulate adenylate cyclase by measuring cAMP produced in head membrane homogenates of fifth instar larvae of the silkworm Bombyx mori. Among the compounds tested, 5‐(4‐methoxyphenyl)oxazole (9) and the 2,6‐dichlorophenyl congener showed the highest activation of adenylate cyclase; both compounds produced approximately half the level of cAMP produced by the action of octopamine (OCT). The OCT receptor antagonists chlorpromazine, mianserin, and metoclopramide attenuated 9‐stimulated cAMP production. In contrast, 5‐(4‐hydroxyphenyl)oxazole (8) and the 4‐cyanophenyl congener attenuated both OCT‐stimulated and basal cAMP production. The tyramine (TYR) receptor antagonist yohimbine inhibited the negative effect of 8. These findings indicate that the 5PO class of compounds includes both positive and negative modulators of adenylate cyclase in the heads of B. mori larvae, and that 9 and 8 are OCT and TYR receptor agonists, respectively. These compounds might prove useful for a pharmacological dissection of biogenic amine receptors. Arch. Insect Biochem. Physiol. 52:7–16, 2003. © 2003 Wiley‐Liss, Inc.
Entomogenous fungus Nomuraea rileyi inhibits host insect molting by C22‐oxidizing inactivation of hemolymph ecdysteroids
Authors: Kiuchi Makoto , Yasui Hiroe , Hayasaka Shoji , Kamimura Manabu 
Published: December 2002

AbstractThe entomogenous fungus Nomuraea rileyi reportedly secretes a proteinaceous substance inhibiting larval molt and metamorphosis in the silkworm Bombyx mori. We studied the possibility that N. rileyi controls B. mori development by inactivating hemolymph molting hormone, ecdysteroids. Incubation of ecdysone (E) and 20‐hydroxyecdysone (20E) in fungal‐conditioned medium resulted in their rapid modification into products with longer retention times in reverse‐phase HPLC. Each modified product from E and 20E was purified by HPLC, and identified by NMR as 22‐dehydroecdysone and 22‐dehydro‐20‐hydroxyecdysone. Some other ecdysteroids with a hydroxyl group at position C22 were also modified. Injection of the fungal‐conditioned medium into Bombyx mori larvae in the mid‐4th instar inhibited larval molt but induced precocious pupal metamorphosis, and its injection into 5th instar larvae just after gut purge blocked pupal metamorphosis. In hemolymph of injected larvae, E and 20E disappeared and, in turn, 22‐dehydroecdysone and 22‐dehydro‐20‐hydroxyecdysone accumulated. These results indicate that N. rileyi secretes a specific enzyme that oxidizes the hydroxyl group at position C22 of hemolymph ecdysteroids and prevents molting in B. mori larvae. Arch. Insect Biochem. Physiol. 52:35–44, 2003. © 2003 Wiley‐Liss, Inc.
Monoclonal antibodies to elongation factor‐1α inhibit in vitro translation in lysates of Sf21 cells
Authors: Stuart M.K. , Chamberlain N.R. 
Published: December 2002

AbstractElongation factor‐1α (EF‐1α) is an enzyme that is essential for protein synthesis. Although EF‐1α offers an excellent target for the disruption of insect metabolism, agents known to interfere with EF‐1α activity are toxic to humans. In this article, we describe the development of monoclonal antibodies (MAbs) that can disrupt the activity of insect EF‐1α without cross‐reacting with the human enzyme. MAbs were generated to EF‐1α from Sf21 cells derived from the fall armyworm, Spodoptera frugiperda, by immunizing mice with EF‐1α eluted from SDS‐PAGE gels. The MAbs reacted with EF‐1α in eggs and first through fifth instars of the fall armyworm in immunoblots of SDS‐PAGE gels, but did not recognize EF‐1α in human carcinoma cells and normal tissues. MAbs with the ability to recognize EF‐1α in its native conformation, identified through immunoprecipitation experiments, were added to Sf21 cell lysates to determine whether the antibodies could inhibit incorporation of [35S]methionine into newly synthesized in vitro translation products. Of the four EF‐1α‐specific MAbs tested, three significantly inhibited protein synthesis when compared to the negative control antibody (P < 0.001, one‐way ANOVA; followed by Dunnett's test, P < 0.05). Arch. Insect Biochem. Physiol. 52:17–34, 2003. © 2003 Wiley‐Liss, Inc.
Hemolymph ecdysteroids do not affect vitellogenesis in the lubber grasshopper
Authors: Hatle John D. , Juliano Steven A. , Borst David W. 
Published: December 2002

AbstractThe role of hemolymph ecdysteroids in the reproduction of non‐dipteran insects is unclear. We examine the role(s) of hemolymph ecdysteroids during egg production in the lubber grasshopper, Romalea microptera. In all individuals, hemolymph ecdysteroids rose to a sharp peak with similar maxima and then fell to undetectable levels. The time from the adult molt to the maximum ecdysteroid titer (Emax titer) varied in response to food availability, whereas the time from Emax titer to oviposition was unrelated to food availability. Because both the timing of egg production and the timing of Emax responded similarly to environmental changes, ecdysteroids may be involved in egg production. We hypothesized that this role is the stimulation of vitellogenesis. Ovariectomized females had vitellogenin but no ecdysteroids, so ecdysteroids are not necessary for vitellogenin production. In addition, treatment of females with ecdysteroids altered neither Vg titers nor ovarian growth. Ovarian ecdysteriods increased at the same age in development as hemolymph ecdysteroids. In contrast to hemolymph ecdysteroids, ovarian ecdysteroids persisted until oviposition. Despite this, [3H]ecdysone injected into the hemolymph was detected later only at very low levels in the ovary, suggesting that hemolymph ecdysteroids are not sequestered by the ovary. In summary, our studies indicate that hemolymph ecdysteroids in adult females of the lubber grasshopper are associated with the timing of egg production, but they neither regulate vitellogenesis nor act as a source of ecdysteroids for the ovary. Arch. Insect Biochem. Physiol. 52:45–57, 2003. © 2003 Wiley‐Liss, Inc.
Environment for engineering design, analysis, and simulation for education using MATLAB via the World Wide Web. I. Environment description and development
Authors: Shiakolas P. S. , Chandra V. , Kebrle J. 
Published: December 2002

AbstractIn Part I of this paper, we present the development of tools for engineering design, analysis and simulation over the World Wide Web accessible via a web browser. The tools utilize the power and versatility provided by the software package MATLAB and the features of the web toolbox. This work aims at improving the understanding of engineering fundamentals through interactive real‐time simulation. The current environment consists of a number of modules for the interactive real‐time simulation of linear time invariant dynamic systems and for analysis and synthesis of planar mechanisms. The properly designed input interface facilitates the easy understanding of the required inputs from the user. The returned information to the user's web browser consists of ASCII (textual), graphical, and pictorial representations, and provides information of the input and solutions. In addition, where appropriate, the user has the option to view an animation of the system. This work demonstrates advantages of using this technology to aid in classroom instruction, ease of implementation for application in other domains, and provides valuable analysis tools to students and engineering professionals. Examples will be presented in Part II to demonstrate the developed tools. Users with access to the Internet can use the developed mechanism synthesis and analysis modules at http://zodhia.uta.edu/development. © 2002 Wiley Periodicals, Inc. Comput Appl Eng Educ 10: 99–108, 2002; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.10018
Environment for engineering design, analysis, and simulation for education using MATLAB via the World Wide Web. II. Representative examples—System simulation and planar mechanism synthesis and analysis
Authors: Shiakolas P. S. , Chandra V. , Kebrle J. , Wilhite D. 
Published: December 2002

AbstractIn Part II of this paper, we present representative examples that demonstrate the capabilities and features of the developed education environment that allows one to simulate in real time engineering systems utilizing the power of MATLAB through a web browser interface. The web‐based graphical user interface (GUI) provides the means for the user to input system parameters and the display of the analysis results. The examples presented demonstrate the required clarity of the developed GUI, and the nature and type of the results returned to the web browser of the user in real time. This environment has the capability to return to the user textual, graphical, pictorial, and animation related material. The user has the option to download analysis results in any of the generated forms to the client computer. This work demonstrates the ease of implementation and advantages of using this technology to aid in classroom instruction. Users with Internet can access the developed simulation modules at http://zodhia.uta.edu/development. © 2002 Wiley Periodicals, Inc. Comput Appl Eng Educ 10: 109–120, 2002; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.10019
Interactive Web‐based package for computer‐aided learning of structural behavior
Authors: Yuan X. F. , Teng J. G. 
Published: December 2002

AbstractThis paper presents an innovative Web‐based package named CALSB for computer‐aided learning of structural behavior. The package was designed to be widely accessible through the Internet, user‐friendly by the automation of many input functions and the extensive use of cursor movements, and dynamically interactive by linking all input and output data to a single graphical display on the screen. The package includes an analysis engine based on the matrix stiffness method, so the response of any two‐dimensional skeletal structure can be predicted and graphically displayed. The package thus provides a virtual laboratory environment in which the user can “build and test” two‐dimensional skeletal structures of unlimited choices to enhance his understanding of structural behavior. In addition, the package includes two other innovative features, structural games and paradoxes. The structural games in the package represent perhaps the first attempt at intentionally combining the learning of structural behavior with joy and excitement, while the structural paradoxes provide a stimulating environment conducive for the development of creative problem solving skills of the user. © 2002 Wiley Periodicals, Inc. Comput Appl Eng Educ 10: 121–136, 2002; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.10020
Web‐based Thermodynamics Tables Wizard
Authors: Ngo C. C. , Lai F. C. 
Published: December 2002

AbstractThis paper presents the Web‐based Thermodynamics Tables Wizard and how it can be used for online courses or web‐teaching to accommodate the need of students at different levels in looking up thermodynamics properties. It can be used as a stand‐alone study aid or an add‐on component for any online Thermodynamics course. The implementation of this Web‐based module has greatly enhanced the learning experience of students in the study of Thermodynamics. © 2002 Wiley Periodicals, Inc. Comput Appl Eng Educ 10: 137–143, 2002; Published online in Wiley InterScience ( www.interscience.wiley.com); DOI 10.1002/cae.10022
Use of process simulators for the unit operations education of undergraduate chemical engineers
Authors: Fernandes Fabiano A. N. 
Published: December 2002

AbstractComputer aided design has become extremely popular and its use in classroom can be very helpful, adding more analysis capabilities to all chemical engineering areas. Process simulators, such as Hysys and Aspen, are complex tools and students tend to have doubts when they start using them. This article presents Hyduc, an exercise/tutorial software, developed to introduce process simulators to undergraduate students and to provide unit operation courses with realistic exercises involving simulation of chemical processes. © 2002 Wiley Periodicals, Inc. Comput Appl Eng Educ 10: 155–160, 2002; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.10023
Digital simulation of wave motion
Authors: Riera Jaime , Giménez Marcos H. , Vidaurre Ana , Monsoriu Juan A. 
Published: December 2002

AbstractInformation and communication technologies have been shown to be very effective in the transmission of scientific knowledge. Nowadays, the development of software and hardware makes it possible to simulate processes as close to reality as we want. However, when we are trying to explain some complex physical processes, it is better to simplify the problem by means of simplified pictures of the total process. In the present work, we analyze the design of a simulation program of wave motion developed in our laboratory. The aim of the program is to help students to understand the basic concepts of the wave motion. For this reason, we have paid special attention to interactivity and graphic aspects. © 2002 Wiley Periodicals, Inc. Comput Appl Eng Educ 10: 161–166, 2002; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.10025
TriMeDeC tool for preparing visual teaching materials based on triangular networks
Authors: Krivograd Sebastian , Žalik Borut , Novak Franc 
Published: December 2002

AbstractTriangular meshes are frequently used to present different natural phenomena and free‐form shapes. They are generated by different mathematical, simulation, and design tools. Usually they contain a huge number of triangles, which represents a serious obstacle for storing, manipulation, and transmission via internet. However, triangular meshes can be simplified (decimated) yet still preserving the main features of the original mesh. In this paper, TriMeDeC tool for decimation, undecimation, and compression of triangular meshes is presented. The tool helps teachers and students to visualize triangular meshes and simplify them in an interactive way. Its salient feature is an effective data compression algorithm, which produces 2 to 3.5 times smaller output files than the popular WinZIP algorithm. TriMeDeC is very simple to use and can be easily employed by teachers and students. © 2002 Wiley Periodicals, Inc. Comput Appl Eng Educ 10: 144–154, 2002; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.10031
Non‐triviality and identification of a constrained Tucker3 analysis
Authors: ten Berge Jos M. F. , Smilde Age K. 
Published: December 2002

AbstractProperties of estimated parameters of models of chemical systems are important. This paper focuses on two properties of such estimated parameters: triviality and uniqueness. If a chemical system is analyzed using a Tucker3 model, then the resulting core can often be rotated to a simple structure containing zeros. This means that it is possible that a prespecified pattern of zero and non‐zero elements of the core, as used in e.g. constrained Tucker3 models, is not an active constraint; that is, the zeros can be obtained trivially for free. Once a non‐trivial pattern of zeros in the core is specified, the question arises whether this pattern is sufficient for obtaining unique loadings. Both issues are discussed in this paper and it is shown that the model used by Gurden et al. (J. Chemometrics 2001; 15: 101–121) does essentially involve a non‐trivial core and implies rotationally unique parameter estimates. Copyright © 2002 John Wiley & Sons, Ltd.
Application of equality constraints on variables during alternating least squares procedures
Authors: Van Benthem Mark H. , Keenan Michael R. , Haaland David M. 
Published: December 2002

AbstractWe describe several methods of applying equality constraints while performing procedures that employ alternating least squares. Among these are mathematically rigorous methods of applying equality constraints, as well as approximate methods, commonly used in chemometrics, that are not mathematically rigorous. The rigorous methods are extensions of the methods described in detail in Lawson and Hanson's landmark text on solving least squares problems, which exhibit well‐behaved least squares performance. The approximate methods tend to be easy to use and code, but they exhibit poor least squares behaviors and have properties that are not well understood. This paper explains the application of rigorous equality‐constrained least squares and demonstrates the dangers of employing non‐rigorous methods. We found that in some cases, upon initiating multivariate curve resolution with the exact basis vectors underlying synthetic data overlaid with noise, the approximate method actually results in an increase in the magnitude of residuals. This phenomenon indicates that the solutions for the approximate methods may actually diverge from the least squares solution. Copyright © 2002 John Wiley & Sons, Ltd.
A simple spatio‐temporal procedure for the prediction of air pollution levels
Authors: Mendes Jorge M. , Turkman Kamil F. 
Published: December 2002

AbstractIn this paper we study the spatio‐temporal behaviour of air pollutants measured daily over the city of Lisbon, Portugal. Our specific aim is to predict air pollutant levels in time and space over a fine grid of locations based on observations from a small number of monitoring sites. Our suggested prediction procedure is based on the simple and intuitive idea of first making predictions in time at the monitoring sites and then extending these predictions in space to locations other than the monitoring sites using kriging methods. Copyright © 2002 John Wiley & Sons, Ltd.
Gedanken zur Zukunft der Feststoffverfahrenstechnik
Authors: Feise H.J. 
Published: December 2002

AbstractDie chemische Industrie erlebt derzeit große Veränderungen. Für die Zukunft erwarten die im „Solids Processing Industrial Network“ beteiligten Experten, dass sich zwei verschiedene Arten von chemischen Anlagen entwickeln: einerseits die vielseitige, modularisierte Mehrzweckanlage und andererseits „World scale“‐Großanlagen. Gleichzeitig wird der bereits hohe Anteil von Feststoffen unter den Produkten der chemischen Industrie weiter steigen und neue Anforderungen stellen: Die Kleinmengenprodukte müssen individuell auf die Bedürfnisse des jeweiligen Kunden zugeschnitten werden, wodurch Product Design zu einer den Wettbewerb bestimmenden Technologie wird. Bei Großanlagen müssen neue Technologien entwickelt werden, welche die notwendigen, hohen Durchsätze bereitstellen und außerdem vom Labor‐ auf World scale‐Maßstab hochskaliert werden können. Einen erheblichen Anteil am künftigen Erfolg wird die Automatisierung haben, deren Einsatz zum Großteil von der Verfügbarkeit geeigneter Inline‐Messsysteme und der Entwicklung von Modellen zur Simulation des Prozesses und der dazugehörigen Partikeleigenschaften abhängen wird.
Ein wenig beachteter Aspekt der Chemiedidaktik: Die Person des Didaktikers
Authors: Martin‐Beyer Wolfgang 
Published: December 2002

AbstractDIE FALLENDEN STUDENTENZAHLEN in den Studiengängen der Chemie werden vielfach dem gymnasialen Chemieunterricht zur Last gelegt [1]. Dabei nehmen kritische Stimmen zum Mittelstufenunterricht [2] zu, in dem die Weichen für das Wahlverhalten in der Oberstufe und fürs Studium gestellt werden. Auch in CHEMKON häufen sich in der letzten Zeit Artikel, in denen neue Konzepte für den Chemieunterricht gefordert oder vorgeschlagen werden oder in denen gar eine gänzlich neue Herangehensweise gefordert wird. Dies wird flankiert von einer Vielzahl von regionalen Schülerwettbewerben und örtlichen Schülerlaboren.Vereinzelt beginnen auch Untersuchungen der Gründe des Unbehagens. Ein Aspekt scheint mir dabei entweder zu wenig oder zu selten bedacht oder ausgesprochen zu werden: die personale Komponente der Fachdidaktik, d.h. die Fachdidaktiker1 selbst. Ich möchte meine Ansichten begründen aus der Beobachtung a) von Zeitschriftenartikeln und b) von Fachvorträgen.
Chemie im Kontext auch für die Sekundarstufe I: Cola und Ketchup im Anfangsunterricht
Authors: Schmidt Silvia , Rebentisch Detlef , Parchmann Ilka 
Published: December 2002

AbstractCOLA UND KETCHUP, das klingt nach einem neuerlichen Aufwärmen der Forderung nach einer stärkeren Alltagsorientierung des Chemieunterrichts, vielleicht bei vielen verbunden mit der Sorge, die fachliche Tiefe fiele rein oberflächlichen Betrachtungen alltäglicher Phänomene zum Opfer oder die interne Systematik des Fachs würde verloren gehen. Wir stimmen Hans Rudolf Christen zu, wenn er feststellt, dass der gymnasiale Chemieunterricht nicht zur „Haushaltskunde”︁ werden darf [1]. Mit Cola und Ketchup kann aber auch an grundlegende Forderungen aus der Lehr‐Lern‐Forschung erinnert werden: Das Aufgreifen von Interessen und Fragen der Schülerinnen und Schüler sowie die Integration komplexer und alltagsnaher, authentischer Problemstellungen in den Unterricht stellt ein zentrales Element der Ansätze zum situierten oder problemorientierten Lernen dar [2, 3]. Welche Fragen ergeben sich diesbezüglich rund um Cola oder Ketchup, die auch zur Erarbeitung grundlegender und anschlussfähiger chemischer Kenntnisse führen können? (Wie) Werden damit Ziele im Sinne einer erfolgreichen Kompetenzentwicklung oder dem Aufbau einer „Scientific Literacy”︁ [4] realisiert? (Wie) Können neue Impulse oder andere konzeptionelle Ansätze tatsächlich zu einer (nachhaltigen) Veränderung von Unterricht führen? Diese Fragen sollen im nachfolgenden Beitrag auf der Basis konzeptioneller Überlegungen und unterrichtspraktischer Erfahrungen erörtert werden; ferner wird ein Projekt zur Weiterentwicklung von Unterricht vorgestellt, in dessen Rahmen die hier beschriebenen Arbeiten einzuordnen sind.