527 research outputs found

    PAPNUM (version 3.0) a finite element modeling and preprocessing system

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    "The purpose of this study is to develop the automated modeling of NASTRAN [2] Rod and Bar elements in the finite element modeling program PAPNUM, which includes the defini­ tion of the geometry and structural properties of all rod and bar elements in the finite element model. The necessary NASTRAN Bulk Data cards are automatically generated. The acronym NASTRAN is formed from NAsa STRuctural ANalysis, and the program has its origins in the research councils of NASA. The acronym PAPNUM is formed from Pre- And Post-processing of NASTRAN at the University of Missouri. PAPNUM version 2.0 [8] was written at the University of Missouri-Columbia, and allows the user to interactively build a finite element model using plate elements at a com­ puter terminal for subsequent NASTRAN processing without requiring the user to know the details of data coding for NASTRAN. PAPNUM allows the user to define the geometry, structural properties, constraints and loads of the finite element model. For user verification a three-dimensional graphics package allows the user to manipulate the view of the model. PAPNUM currently supports the following types of NASTRAN rigid formats: 1. Static Analysis 2. Normal Mode Analysis 3. Elastic Stability (Buckling) Analysis."--Page 2.Includes bibliographical references

    NASA newsletters for the Weber Student Shuttle Involvement Project

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    Biweekly reports generated for the Weber Student Shuttle Involvement Project (SSIP) are discussed. The reports document the evolution of science, hardware, and logistics for this Shuttle project aboard the eleventh flight of the Space Transportation System (STS-41B), launched from Kennedy Space Center on February 3, 1984, and returned to KSC 8 days later. The reports were intended to keep all members of the team aware of progress in the project and to avoid redundancy and misunderstanding. Since the Weber SSIP was NASA's first orbital rat project, documentation of all actions was essential to assure the success of this complex project. Eleven reports were generated: October 3, 17 and 31; November 14 and 28; and December 12 and 17, 1983; and January 3, 16, and 23; and May 1, 1984. A subject index of the reports is included. The final report of the project is included as an appendix

    Fieldwork between folders: fragments, traces, and the ruins of colonial archives

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    Prädation von Unkrautsamen durch samenfressende Carabiden unter dem Einfluss karnivorer Carabiden

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    Die Samenprädation an Unkrautsamen wird von biotischen Faktoren reguliert und von abiotischen Faktoren beeinflusst. Kenntnisse über diese Effekte sind notwendig, um die Samenprädation zur Unkrautkontrolle gezielt einsetzen zu können. Hier wurde die Fragestellung bearbeitet, ob karnivore Carabiden die Samenprädation negativ beeinflussen. Zusätzlich wurde der Einfluss der Witterung auf die Prädation untersucht. Dazu wurde in Nordostdeutschland über 23 Tage ein Feldversuch (Blockanlage mit vier Prüfgliedern und drei Wiederholungen) in konventionellem Winterweizen angelegt. In 1 m² großen Rahmen wurden Carabidenarten mit granivorer (Pseudoophonus rufipes, Harpulus affinis) Ernährungsweise ausgesetzt. In einer weiteren Versuchsvariante wurden zusätzlich karnivore Carabiden (Pterostichus melanarius, Poecilus cupreus) hinzugesetzt. Weitere Versuchsvarianten waren die natürliche Carabidenzusammensetzung und leer gefangene Rahmen. Die Samenprädation wurde täglich mit Hilfe von Samenkarten ermittelt, die mit Samen von Poa annua und Stellaria media bestückt waren. Temperatur, relative Luftfeuchte und täglicher Niederschlag wurden als Kovariablen erfasst. Die Samenprädation lag in der Variante mit granivoren Carabiden bei 54,3 (P. annua) bzw. 14,3 (S. media) Samen pro Rahmen und Tag. In Rahmen, in denen zu den granivoren Carabiden zusätzlich karnivore Carabiden gesetzt worden waren, war die Prädation von P. annua mit 46,6 Samen pro Rahmen und Tag signifikant niedriger (gepaarter Wilcoxon-Test, p = 0.04), bei S. media mit 14,4 ähnlich hoch. In Rahmen mit natürlicher Art- und Dichtezusammensetzung der Carabidengemeinschaft fehlten mit 9,1 Samen von P. annua und 7,2 Samen von S. media pro Rahmen und Tag signifikant mehr Samen als in den leer gefangenen Rahmen (gepaarter Wilcoxon-Test, p ≤ 0.002). Für den Samenfraß in den mit Käfern besetzten Rahmen wurde die minimale Nachttemperatur als einzige signifikante erklärende Wettervariable gefunden. Die Arbeiten tragen dazu bei, ein besseres Bild von den Bestimmungsfaktoren der Samenprädation im Feld zu erhalten.Stichwörter: Biologische Unkrautbekämpfung, Harpalus affininis, Laufkäfer, Pseudoophonus rufipes, Samenfraß, WirbelloseWeed seed predation by granivorous carabids as influenced by carnivorous carabidsAbstractWeed seed predation is influenced for both biological and abiotic factors. Knowledge about these factors is necessary to optimize seed predation as a biological weed control measure. Here, we asked whether carnivorous carabid beetles can affect the seed predation. Additionally, the effect of weather on seed predation rate was investigated. For this purpose, 12, 1m² enclosures were installed in a field (block design with four treatments and three replications) in northeastern Germany over a period of 23 days. Treatments in the enclosures were 1) without carabids, 2) with a natural density and species composition of carabids, 3) with granivorous carabid beetles (Pseudoophonus rufipes, Harpulus affinis), and 4) as 3) but additionally with carnivorous carabids (Pterostichus melanarius, Poecilus cupreus) Seed predation rate was determined daily using seed cards with Poa annua and Stellaria media seeds. Temperature, relative air humidity and daily precipitation were measured as covariables. In the treatment with granivorous carabids seed predation rate was 54.3 (P. annua) resp. 14.3 (S. media) seeds per enclosure and day. In the treatment with granivorous and carnivorous carabids, seed predation rate was significantly lower for P. annua (46.6 seeds per enclosure and day, paired Wilcoxon-Test, p = 0.04) and equally high for S. media (14.4 seeds per enclosure and day). In enclosures containing non-manipulated carabid densities 9.1 seeds of P. annua and 7.2 seeds of S. media were lost per enclosure and per day, which is significantly higher than from enclosures that were void of carabids. The minimum night temperature was the only weather variable that significantly influenced seed predation rate. This work contributes to a better understanding of the factors influencing seed predation rates in the field.Keywords: Biological weed control, ground beetle, Harpalus affininis, invertebrates, Pseudoophonus rufipes, seed consumptio

    Detailing renal hemodynamics and oxygenation in rats by a combined near-infrared spectroscopy and invasive probe approach

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    We hypothesize that combining quantitative near-infrared spectroscopy (NIRS) with established invasive techniques will enable advanced insights into renal hemodynamics and oxygenation in small animal models. We developed a NIRS technique to monitor absolute values of oxygenated and deoxygenated hemoglobin and of oxygen saturation of hemoglobin within the renal cortex of rats. This NIRS technique was combined with invasive methods to simultaneously record renal tissue oxygen tension and perfusion. The results of test procedures including occlusions of the aorta or the renal vein, hyperoxia, hypoxia, and hypercapnia demonstrated that the combined approach, by providing different but complementary information, enables a more comprehensive characterization of renal hemodynamics and oxygenation

    Comprehension as social and intellectual practice: Rebuilding curriculum in low socioeconomic and cultural minority schools

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    This article reframes the concept of comprehension as a social and intellectual practice. It reviews current approaches to reading instruction for linguistically and culturally diverse and low socioeconomic students, noting an emphasis on comprehension as autonomous skills. The Four Resources model (Freebody & Luke, 1990) is used to make the case for the integration of comprehension instruction with an emphasis on student cultural and community knowledge, and substantive intellectual and sociocultural content in elementary school curricula. Illustrations are drawn from research underway on the teaching of literacy in primary schools in low SES communities

    What Does Weight Have to Do with It? Parent Perceptions of Weight and Pain in a Pediatric Chronic Pain Population

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    Tailored pain management strategies are urgently needed for youth with co-occurring chronic pain and obesity; however, prior to developing such strategies, we need to understand parent perspectives on weight in the context of pediatric chronic pain. Participants in this study included 233 parents of patients presenting to a multidisciplinary pediatric chronic pain clinic. Parents completed a brief survey prior to their child\u27s initial appointment; questions addressed parents\u27 perceptions of their child\u27s weight, and their perceptions of multiple aspects of the relationship between their child\u27s weight and chronic pain. The majority (64%) of parents of youth with obesity accurately rated their child\u27s weight; this group of parents was also more concerned (p \u3c 0.05) about their child\u27s weight than parents of youth with a healthy weight. However, the majority of parents of youth with obesity did not think their child\u27s weight contributed to his/her pain, or that weight was relevant to their child\u27s pain or pain treatment. Overall, only half of all parents saw discussions of weight, nutrition, and physical activity as important to treating their child\u27s pain. Results support the need for addressing parents\u27 perceptions of their child\u27s weight status, and educating parents about the relationship between excessive weight and chronic pain

    Multi-model projections of future evaporation in a sub-tropical lake

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    Lake evaporation plays an important role in the water budget of lakes. Predicting lake evaporation responses to climate change is thus of paramount importance for the planning of mitigation and adaption strategies. However, most studies that have simulated climate change impacts on lake evaporation have typically utilised a single mechanistic model. Whilst such studies have merit, projected changes in lake evaporation from any single lake model can be considered uncertain. To better understand evaporation responses to climate change, a multi-model approach (i.e., where a range of projections are considered), is desirable. In this study, we present such multi-model analysis, where five lake models forced by four different climate model projections are used to simulate historic and future change (1901–2099) in lake evaporation. Our investigation, which focuses on sub-tropical Lake Kinneret (Israel), suggested considerable differences in simulated evaporation rates among the models, with the annual average evaporation rates varying between 1232 mm year−1 and 2608 mm year−1 during the historic period (1901–2005). We explored these differences by comparing the models with reference evaporation rates estimated using in-situ data (2000–2005) and a bulk aerodynamic algorithm. We found that the model ensemble generally captured the intra-annual variability in reference evaporation rates, and compared well at seasonal timescales (RMSEc = 0.19, R = 0.92). Using the model ensemble, we then projected future change in evaporation rates under three different Representative Concentration Pathway (RCP) scenarios: RCP 2.6, 6.0 and 8.5. Our projections indicated that, by the end of the 21st century (2070–2099), annual average evaporation rates would increase in Lake Kinneret by 9–22 % under RCPs 2.6–8.5. When compared with projected regional declines in precipitation, our projections suggested that the water balance of Lake Kinneret could experience a deficit of 14–40 % this century. We anticipate this substantial projected deficit combined with a considerable growth in population expected for this region could have considerable negative impacts on water availability and would consequently increase regional water stress
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