1,446 research outputs found
Longitudinal Study of the Attitudes and Behaviors of Environmental Education Program Participants.
The goal of this longitudinal study was to measure the attitudes and behaviors of participants of the Marsh Maneuvers program over the course of the last 25 years. The goal of the Marsh Maneuvers program is to educate students into becoming environmentally literate adults. Environmental literacy is considered herein to be people possessing knowledge about and positive attitudes and behaviors towards the environment. Although students learn basic science and environmental knowledge in the classroom, true environmental literacy is believed to require more hands-on understanding of the material. To evaluate the effectiveness of the program, the following three objectives were completed. Lesson plans for the Marsh Maneuvers camp were developed in order to identify specific concepts being taught. The short-term knowledge retention of the Marsh Maneuvers participants was analyzed using pre-and posttests. Finally, the long-term impact of the Marsh Maneuvers program over the past 25 years was determined using a survey. When analyzing the short-term retention results, there was a 36% average increase in knowledge between pre and posttests, which was significant. Nontraditional education programs are designed to overcome barriers that can be presented in a traditional classroom setting (gender, age, GPA). All participants, regardless of gender, age, or GPA, saw an increase in knowledge during the program. The long-term survey results showed that Marsh Maneuvers participants had slightly more positive attitudes and behaviors. The Marsh Maneuvers participants demonstrated environmental knowledge similar to the control group with only one question being statistically significant between the two groups. Marsh Maneuvers is an effective informal education program to increase environmental literacy for 4-H members in Louisiana based on short and long term study results
Independent association of resting energy expenditure with blood pressure: confirmation in populations of the African diaspora
Obesity is a major risk factor for hypertension, however, the physiologic mechanisms linking increased adiposity to elevations in blood pressure are not well described. An increase in resting energy expenditure (REE) is an obligatory consequence of obesity. Previous survey research has demonstrated that REE is an independent predictor of blood pressure, and eliminates the co-linear association of body mass index. This observation has received little attention and there have been no attempts to provide a causal explanation
Évaluation de quelques sources d’erreur dans un inventaire semi-automatisé de l’utilisation agricole du sol : étude de cas à Sainte-Foy
Un inventaire de l'occupation du sol pour chaque terrain agricole peut être produit par le croisement (automatisé) entre une image satellitaire classifiée et une image des terrains, provenant du cadastre numérisé. Trois sources d'erreur sont examinées. L'erreur planimétrique, créée par la « rasteurisation » des polygones-terrain, Terreur dans les proportions des classes d'occupation du sol due à la résolution spatiale, et l'erreur de la classification elle-même. Les résultats démontrent que chacune de ces erreurs varie en fonction des terrains, donnant des inventaires de qualité inégale. Il est difficile de le corréler avec les dimensions des terrains, et de fixer ainsi des dimensions minimales nécessaires au succès de l'inventaire agricole dans un milieu péri-urbain.An inventory of the land cover per individual agricultural plot can be produced by the cross-tabulation of a classified satellite image and an image of plots provided by the digitized land survey of the region. Three sources of error are examined. The planimetric error, created by the rasterization of the ground polygons, the proportional error in the land cover classes due to the spatial resolution and lastly, the classification error itself. The results show that each of these errors varies in relation to the land parcels which produces inventories of unequal quality. It is difficult to correlate them with the plot dimensions, and thus to set the minimal dimensions required to insure the success of the agricultural inventory in a suburban area
Recommended from our members
Gut microbial features can predict host phenotype response to protein deficiency.
Malnutrition remains a major health problem in low- and middle-income countries. During low protein intake, <0.67 g/kg/day, there is a loss of nitrogen (N2 ) balance, due to the unavailability of amino acid for metabolism and unbalanced protein catabolism results. However, there are individuals, who consume the same low protein intake, and preserve N2 balance for unknown reasons. A novel factor, the gut microbiota, may account for these N2 balance differences. To investigate this, we correlated gut microbial profiles with the growth of four murine strains (C57Bl6/J, CD-1, FVB, and NIH-Swiss) on protein deficient (PD) diet. Results show that a PD diet exerts a strain-dependent impact on growth and N2 balance as determined through analysis of urinary urea, ammonia and creatinine excretion. Bacterial alpha diversity was significantly (P < 0.05, FDR) lower across all strains on a PD diet compared to normal chow (NC). Multi-group analyses of the composition of microbiomes (ANCOM) revealed significantly differential microbial signatures between the four strains independent of diet. However, mice on a PD diet demonstrated differential enrichment of bacterial genera including, Allobaculum (C57Bl6/J), Parabacteroides (CD-1), Turicibacter (FVB), and Mucispirillum (NIH-Swiss) relative to NC. For instance, selective comparison of the CD-1 (gained weight) and C57Bl6/J (did not gain weight) strains on PD diet also demonstrated significant pathway enrichment of dihydroorodate dehydrogenase, rRNA methyltransferases, and RNA splicing ligase in the CD-1 strains compared to C57Bl6/J strains; which might account in their ability to retain growth despite a protein deficient diet. Taken together, these results suggest a potential relationship between the specific gut microbiota, N2 balance and animal response to malnutrition
Phylogenetic analysis of bacterial and archaeal arsC gene sequences suggests an ancient, common origin for arsenate reductase
BACKGROUND: The ars gene system provides arsenic resistance for a variety of microorganisms and can be chromosomal or plasmid-borne. The arsC gene, which codes for an arsenate reductase is essential for arsenate resistance and transforms arsenate into arsenite, which is extruded from the cell. A survey of GenBank shows that arsC appears to be phylogenetically widespread both in organisms with known arsenic resistance and those organisms that have been sequenced as part of whole genome projects. RESULTS: Phylogenetic analysis of aligned arsC sequences shows broad similarities to the established 16S rRNA phylogeny, with separation of bacterial, archaeal, and subsequently eukaryotic arsC genes. However, inconsistencies between arsC and 16S rRNA are apparent for some taxa. Cyanobacteria and some of the γ-Proteobacteria appear to possess arsC genes that are similar to those of Low GC Gram-positive Bacteria, and other isolated taxa possess arsC genes that would not be expected based on known evolutionary relationships. There is no clear separation of plasmid-borne and chromosomal arsC genes, although a number of the Enterobacteriales (γ-Proteobacteria) possess similar plasmid-encoded arsC sequences. CONCLUSION: The overall phylogeny of the arsenate reductases suggests a single, early origin of the arsC gene and subsequent sequence divergence to give the distinct arsC classes that exist today. Discrepancies between 16S rRNA and arsC phylogenies support the role of horizontal gene transfer (HGT) in the evolution of arsenate reductases, with a number of instances of HGT early in bacterial arsC evolution. Plasmid-borne arsC genes are not monophyletic suggesting multiple cases of chromosomal-plasmid exchange and subsequent HGT. Overall, arsC phylogeny is complex and is likely the result of a number of evolutionary mechanisms
Asynchronous Course Delivery: Instructor and Student Views
Accompanying the projected growth in computers, bandwidth improvements will make Internet use a more satisfying experience, leading to increased usage. It follows that faculty in higher education will explore strategies that increase student achievement and satisfaction in asynchronous teaching and learning. Use of the Internet for course and program delivery will increase. The potential of the Web as both a set of tools and a medium for course delivery offers limitless possibilities for creating innovative course design that can be more effective than some classroom experiences (Hafner & Oblinger, 1998). There is evidence that building an online community begins with establishing good online program administration. Central to this is the infrastructure to support online delivery coupled with the faculty who create, deliver, and manage the courses. The debate continues among educators as to the effectiveness of asynchronous teaching and learning in higher education. Some argue it provides a new context for teaching and learning, chiefly because it removes the constraints of time and physical presence
Nontrivial temporal scaling in a Galilean stick-slip dynamics
We examine the stick-slip fluctuating response of a rough massive
non-rotating cylinder moving on a rough inclined groove which is submitted to
weak external perturbations and which is maintained well below the angle of
repose. The experiments presented here, which are reminiscent of the Galileo's
works with rolling objects on inclines, have brought in the last years
important new insights into the friction between surfaces in relative motion
and are of relevance for earthquakes, differing from classical block-spring
models by the mechanism of energy input in the system. Robust nontrivial
temporal scaling laws appearing in the dynamics of this system are reported,
and it is shown that the time-support where dissipation occurs approaches a
statistical fractal set with a fixed value of dimension. The distribution of
periods of inactivity in the intermittent motion of the cylinder is also
studied and found to be closely related to the lacunarity of a random version
of the classic triadic Cantor set on the line.Comment: 7 pages including 6 figure
Maximizing An Ethylene Plant's Turbomachinery Reliability.
LecturePg. 85-90The ethylene plant in DuPont's major petrochemical complex
in Orange, Texas was designed and built in the late 1960s,
using the latest proven technology of that period. From plant
startup in 1967 to 1981, there were eighteen ethylene plant shutdowns
caused by problems associated with the large compressors
and turbines. After two very long outages which occurred
in 1980 and 1981, an extensive turbomachinery upgrading program
was undertaken to improve utility.
This presentation sets forth reasons for the reliability problems
experienced through 1981 and illustrates the program undertaken
to increase equipment utility. This program has allowed
the ethylene plant to run from 1981 to 1989 with only one
turbomachinery related shutdown
Ischemic preconditioning attenuates portal venous plasma concentrations of purines following warm liver ischemia in man
Background/Aims: Degradation of adenine nucleotides to adenosine has been suggested to play a critical role in ischemic preconditioning (IPC). Thus, we questioned in patients undergoing partial hepatectomy whether (i) IPC will increase plasma purine catabolites and whether (ii) formation of purines in response to vascular clamping (Pringle maneuver) can be attenuated by prior IPC. Methods: 75 patients were randomly assigned to three groups: group I underwent hepatectomy without vascular clamping; group II was subjected to the Pringle maneuver during resection, and group III was preconditioned (10 min ischemia and 10 min reperfusion) prior to the Pringle maneuver for resection. Central, portal venous and arterial plasma concentrations of adenosine, inosine, hypoxanthine and xanthine were determined by high-performance liquid chromatography. Results: Duration of the Pringle maneuver did not differ between patients with or without IPC. Surgery without vascular clamping had only a minor effect on plasma purine transiently increased. After the Pringle maneuver alone, purine plasma concentrations were most increased. This strong rise in plasma purines caused by the Pringle maneuver, however, was significantly attenuated by IPC. When portal venous minus arterial concentration difference was calculated for inosine or hypoxanthine, the respective differences became positive in patients subjected to the Pringle maneuver and were completely prevented by preconditioning. Conclusion: These data demonstrate that (i) IPC increases formation of adenosine, and that (ii) the unwanted degradation of adenine nucleotides to purines caused by the Pringle maneuver can be attenuated by IPC. Because IPC also induces a decrease of portal venous minus arterial purine plasma concentration differences, IPC might possibly decrease disturbances in the energy metabolism in the intestine as well. Copyright (C) 2005 S. Karger AG, Basel
- …