855 research outputs found
Ciencia y arte en la ilustración científica
"Ciencia y Arte en la Ilustración Científica" es una publicación que narra la forma en que "las colecciones modernas de historia natural se desarrollaron en los gabinetes o armarios de curiosidades del Renacimiento en Europa. Las colecciones en los primeros gabinetes fueron recolectadas con la intención de buscar orden en el caos de la naturaleza. Durante el Renacimiento, Europa estaba sufriendo cambios inimaginables, y los sistemas existentes de clasificación y de orden no fueron adecuados para entender el mundo. Por ejemplo, a mediados del siglo XVI, muchas especies de plantas y animales desconocidas llegaron a Europa con las expediciones al Nuevo Mundo...
Army Professionalism, the Military Ethic, and Officership in the 21st Century
The authors address what they—and many others—perceived to be a decline in military professionalism in the Army officer corps. The authors first describe the ethical, technical, and political components of military professionalism and then address the causes for the decline. They conclude by proposing a set of principles which, if adhered to, will reinvigorate the vision of the officer corps and motivate the corps to selfless service.https://press.armywarcollege.edu/monographs/1145/thumbnail.jp
Comparison of Pittsburgh compound B and florbetapir in cross-sectional and longitudinal studies
Longevity of Genotype-Specific Immune Responses to Plasmodium falciparum Merozoite Surface Protein 1 in Kenyan Children from Regions of Different Malaria Transmission Intensity
Naturally acquired immunity to Plasmodium falciparum presents a changing landscape as malaria control programs and vaccine initiatives are implemented. Determining which immunologic indicators remain surrogates of past infection, as opposed to mediators of protection, led us to compare stability of immune responses across regions with divergent malaria transmission intensities. A repeat cross-sectional study of Kenyan children from a malaria-holoendemic area and an epidemic-prone area was used to examine longitudinal antibody and interferon-gamma (IFN-gamma) responses to the 3D7 and FVO variants of merozoite surface protein 1 (MSP1). Antibodies to MSP1 were common in both study populations and did not significantly wane over a 21-month time period. IFN-gamma responses were less frequent and rapidly disappeared in children after a prolonged period of no malaria transmission. Antibody and IFN-gamma responses rarely correlated with each other; however, MSP1-specific IFN-gamma response correlated with lack of concurrent P. falciparum parasitemia of the same genotype, though only statistically significantly in the malaria-holoendemic region (odds ratio = 0.31, 95% confidence interval = 0.12-0.84). This study affirms that antimalarial antibodies are informative for evaluation of history of malaria exposure within individuals, whereas cell-mediated immunity, though short lived under natural exposure conditions, might provide an assessment of recent infection and protection from parasitemia
Analysis of small-diameter wood supply in northern Arizona - Final report
Forest management to restore fire-adapted ponderosa pine ecosystems is a central priority of the Southwestern Region of the USDA Forest Service. Appropriately-scaled businesses are apt to play a key role in achieving this goal by harvesting, processing and selling wood products, thereby reducing treatment costs and providing economic opportunities. The manner in which treatments occur across northern Arizona, with its multiple jurisdictions and land management areas, is of vital concern to a diversity of stakeholder groups. To identify a level of forest thinning treatments and potential wood supply from restoration byproducts, a 20-member working group representing environmental non-governmental organizations (NGOs), private forest industries, local government, the Ecological Restoration Institute at Northern Arizona University (NAU), and state and federal land and resource management agencies was assembled. A series of seven workshops supported by Forest Ecosystem Restoration Analysis (ForestERA; NAU) staff were designed to consolidate geographic data and other spatial information and to synthesize potential treatment scenarios for a 2.4 million acre analysis area south of the Grand Canyon and across the Mogollon Plateau. A total of 94% of the analysis area is on National Forest lands. ForestERA developed up-to-date remote sensing-based forest structure data layers to inform the development of treatment scenarios, and to estimate wood volume in three tree diameter classes of 16" diameter at breast height (dbh, 4.5' above base). For the purposes of this report, the group selected a 16" dbh threshold due to its common use within the analysis landscape as a break point differentiating "small" and "large" diameter trees in the ponderosa pine forest type. The focus of this study was on small-diameter trees, although wood supply estimates include some trees >16" dbh where their removal was required to meet desired post-treatment conditions.4 There was no concurrence within the group that trees over 16" dbh should be cut and removed from areas outside community protection management areas (CPMAs)..
Tissue Destruction Resulting from the Interaction of Cytotoxic T Cells and Their Targets a
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73703/1/j.1749-6632.1988.tb36330.x.pd
Survival Outcomes of Patients Treated with Hypofractionated Stereotactic Body Radiation Therapy for Parotid Gland Tumors: a Retrospective Analysis
Background: to review a single-institution experience with the management of parotid malignancies treated by fractionated stereotactic body radiosurgery (SBRT). Findings: Between 2003 and 2011, 13 patients diagnosed with parotid malignancies were treated with adjuvant or definitive SBRT to a median dose of 33 Gy (range 25–40 Gy). There were 11 male and two female patients with a median age of 80. Ten patients declined conventional radiation treatment and three patients had received prior unrelated radiation therapy to neighboring structures with unavailable radiation records. Six patients were treated with definitive intent while seven patients were treated adjuvantly for adverse surgical or pathologic features. Five patients had clinical or pathologic evidence of lymph node disease. Conclusion: at a median follow-up of 14 months only one patient failed locally, and four failed distantly. The actuarial 2-year overall survival, progression-free survival, and local-regional control rates were 46, 84, and 47%, respectively. Statistical analysis revealed surgery as a positive predictor of overall survival while presence of gross disease was a negatively correlated factor (p < 0.05)
Spitzer Observations of the HII Region NGC 2467: An Analysis of Triggered Star Formation
We present new Spitzer Space Telescope observations of the region NGC 2467,
and use these observations to determine how the environment of an HII region
affects the process of star formation. Our observations comprise IRAC (3.6,
4.5, 5.8, and 8.0 um) and MIPS (24 um) maps of the region, covering
approximately 400 square arcminutes. The images show a region of ionized gas
pushing out into the surrounding molecular cloud, powered by an O6V star and
two clusters of massive stars in the region. We have identified as candidate
Young Stellar Objects (YSOs) 45 sources in NGC 2467 with infrared excesses in
at least two mid-infrared colors. We have constructed color-color diagrams of
these sources and have quantified their spatial distribution within the region.
We find that the YSOs are not randomly distributed in NGC 2467; rather, over
75% of the sources are distributed at the edge of the HII region, along
ionization fronts driven by the nearby massive stars. The high fraction of YSOs
in NGC 2467 that are found in proximity to gas that has been compressed by
ionization fronts supports the hypothesis that a significant fraction of the
star formation in NGC 2467 is triggered by the massive stars and the expansion
of the HII region. At the current rate of star formation, we estimate at least
25-50% of the total population of YSOs formed by this process.Comment: Accepted to the Astrophysical Journal, set to appear in Volume 701;
18 pages, 13 figures, 4 tables. This version reflects a few major changes
made in the accepted version, including new figure
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