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Control Section (control + section)
Selected AbstractsRaised water temperature lowers diversity of hyporheic aquatic hyphomycetesFRESHWATER BIOLOGY, Issue 2 2008FELIX BÄRLOCHER Summary 1. The hyporheic zone of a permanent first-order stream was divided into a treatment and a control section using a 1 m deep sheet-metal barrier. During a 4-month pre-treatment period, water temperatures in two transects of the two sections were not different. Upon heating, the water temperature in the treatment transect increased by an average of 4.3 °C over values in the control transect. 2. Eleven bimonthly core samples were taken from a treatment and a control transect, and recovered CPOM was classified as twigs, wood, grass, roots, cedar and deciduous leaves. 3. In both transects, twigs were the most common and deciduous leaves the least common substrates. The number of leaf fragments declined significantly in the heat-treated transect. 4. Diversity and frequencies of occurrence of aquatic hyphomycetes were highest on leaves and lowest on grass and wood. On leaves, their frequency of occurrence was higher in control than in treatment samples. 5. Preliminary results with amplified and cloned 18S DNA sequences revealed many fungal taxa with high affinities to Basidiomycota, particularly to Limnoperdon incarnatum. 6. By itself, higher water temperature due to global warming is likely to lower the availability of substrates for, and therefore the occurrence of, aquatic hyphomycetes. [source] Spatially varied flow in non-prismatic channels.IRRIGATION AND DRAINAGE, Issue 1 2002I: dynamic equation canal d'irrigation; modélisation; écoulement spatialement varié; équation de transfert; analyse numérique; expérimentation Abstract The bottom width of channels carrying spatially varied flow with increasing discharge is usually flared in the flow direction. This produces a non-prismatic section. This paper, based on the law of linear momentum conservation, presents a new form of the governing dynamic equation for flow in such circumstances. In addition to the computed water surface profile, the proposed equation affects the position of the control section and its flow depth as well. Copyright © 2002 John Wiley & Sons, Ltd. RÉSUMÉ La largeur du lit de cours d'eau, variée spatialement par l'augmentation du débit, influence la direction de l'écoulement. Cette procédure crée une coupe irréguliére de cours d'eau. Cet article présente une nouvelle forme de l'équation dynamique dans cette situation de l'écoulement. La méthodologie est basée sur la loi de conservation linéaire de momentum. L'équation proposée est capable de calculer le profil de niveau de l'eau. Elle affecte aussi sur la situation de coupe de contrôle et la profondeur de l'écoulement. Copyright © 2002 John Wiley & Sons, Ltd. [source] Spatially varied flow in non-prismatic channels.IRRIGATION AND DRAINAGE, Issue 1 2002II: numerical solution, experimental verification canal d'irrigation; modélisation; écoulement spatialement varié; équation de transfert; analyse numérique; expérimentation Abstract A new governing equation was proposed for the spatially varied flows with increasing discharge, which affects the position and the depth of the control section as well as the entire water surface profile within the channel. This paper presents the use of the Newton-Raphson method in the solution process. The results of the computational model were compared with experimental data and with the output of the traditional equation. It was indicated that because of incorporating the expansion factor of the non-prismatic channels, the proposed equation is able to represent the experimental data very well and hence is superior to the traditional equation for design purposes. Copyright © 2002 John Wiley & Sons, Ltd. RÉSUMÉ Une nouvelle éeuation a été purposée pour l'écoulement varié spatialement sous la condition de l'augmentation du débit. Cette équation considére la situation et la profondeue de coupe de contrôle et aussi calcule le profil de niveau de l'eau. La solution numérique utilise la méthode de Newton-Raphson. On a comparé les résultata obtenus par ce modéle avec les données expérimentales et la méthode traditionnelle. Cette comparison montre que grâce à l'incorporation du facteur d'expansion d'un cour d'eau irrégulier, la méthode proposée est capable de représenter trés bien les données expérimentales et peut être beaucoup plus efficace pour le motif de dessin par rapport à la méthode traditionnele Copyright © 2002 John Wiley & Sons, Ltd. [source] Animated instructional software for mechanics of materials: Implementation and assessmentCOMPUTER APPLICATIONS IN ENGINEERING EDUCATION, Issue 1 2006Timothy A. Philpot Abstract During the past 3 years, the Basic Engineering Department at the University of Missouri, Rolla has been developing a second-generation suite of instructional software called MecMovies for the Mechanics of Materials course. The MecMovies suite consists of over 110 animated example problems, drill-and-practice games, and interactive exercises. Students generally respond favorably to software of this type; however, much of the data that has been gathered to assess the effectiveness of similar software has been anecdotal. The method by which instructional software is incorporated into the engineering class is partly responsible for this lack of systematic evaluation. Often, software packages have been implemented in the classroom as supplemental material,recommended but not required. In the Fall 2003 semester, MecMovies was integrated thoroughly into the course assignments for one of the six UMR Mechanics of Materials sections. Four professors were involved in the study, and student performance in the experimental MecMovies section was compared to performance in the five control sections through a common final exam. At the end of the semester, students who used the MecMovies software also completed a survey questionnaire consisting of a number of subjective rating items. This paper presents a comparison of student performance in the experimental and control sections along with discussion of student qualitative ratings and comments. © 2006 Wiley Periodicals, Inc. Comput Appl Eng Educ 14: 31,43, 2006; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20065 [source] Density-dependent growth in hatchery-reared brown trout released into a natural streamJOURNAL OF FISH BIOLOGY, Issue 5 2004L. F. Sundström Hatchery-reared brown trout Salmo trutta stocked in a natural stream in addition to resident wild brown trout grew more slowly than those stocked with an experimentally reduced density of brown wild trout. In both cases, hatchery-reared brown trout grew more slowly than resident wild fish in control sections. Mortality and movements did not differ among the three categories of fish. The results showed that growth of stocked hatchery-reared brown trout parr was density-dependent, most likely as a consequence of increased competition. Thus, supplementary release of hatchery-reared fish did not necessarily increase biomass. [source] Mouse oocytes derived from fetal germ cells are competent to support the development of embryos by in vitro fertilizationMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 11 2008Wei Shen Figure 1B in the paper above appeared to be an enlargement of a portion of Figure 1A, while the legend indicated otherwise. This error had been made because the authors labeled the sections by date, but not by source, and because experimental and control sections were similar. The authors have now confirmed their overall results and have submitted new figures for Figure 1 and Figure 4A presented below. The original article to which this erratum refers, was published in Molecular Reproduction and Development 2006;73(10):1312,1317. Mol. Reprod. Dev. 75: 1688,1689, 2008. © 2008 Wiley-Liss, Inc. [source] | |||||||||||||