98 research outputs found
Germinable Soil Seed Bank of \u3ci\u3eBothriochloa macra\u3c/i\u3e Dominated Pasture in South-Eastern Australia
In native pastures, soil seed banks play an important role in conserving the genetic material in a plant population, influencing community structure and providing protection against adverse climatic conditions. One important native grass is Bothrichloa macra (Steud.) S.T.Blake (Red grass, Red-leg grass). This grass is a C4 indigenous perennial grass that is commonly found in native pastures in the high rainfall zone of south-eastern Australia.
At Tarrawingee, NE Victoria, (36°25´S, 146°31´E) and Wymah, southern NSW, (35°58´S, 147°11´E), Australia, two sites that had Bothriochloa macra as the dominant native grass were sampled. Three hundred cores (50 mm diameter and 50 mm depth) were collected from each site and bulked in May 2005. The soil samples were spread evenly over seed raising flats and maintained in a glasshouse, under natural light and modified day/night temperatures. The samples were kept moist for periods of between 35 and 70 d. During each census, germinants were identified to the following functional groups (B. macra, broadleaf, grass and legume) and removed. At the end of each cycle remaining seedlings were counted and water withheld. The dry soil samples were then thoroughly mixed and re-watered to initiate another cohort of germination. This cycle was repeated five times over a nine-month period.
These counts showed that B. macra only represented a very low proportion of the soil seed bank (1.1 to 3.4% of total germinants), with the soil seed bank dominated by annual species. Fifty-eight different species germinated from the soil seed bank, with 83% of all seeds germinating in the first two cycles. The soil seed bank of these B. macra pastures possessed characteristics typical of most soil seed banks, including poor correlation with the standing vegetation, domination by one or two species and low representation of perennial species
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Risk Assessment Using The Homeland-Defense Operational Planning System (HOPS)
The Homeland-Defense Operational Planning System (HOPS), is a new operational planning tool leveraging Lawrence Livermore National Laboratory's expertise in weapons systems and in sparse information analysis to support the defense of the U.S. homeland. HOPS provides planners with a basis to make decisions to protect against acts of terrorism, focusing on the defense of facilities critical to U.S. infrastructure. Criticality of facilities, structures, and systems is evaluated on a composite matrix of specific projected casualty, economic, and sociopolitical impact bins. Based on these criteria, significant unidentified vulnerabilities are identified and secured. To provide insight into potential successes by malevolent actors, HOPS analysts strive to base their efforts mainly on unclassified open-source data. However, more cooperation is needed between HOPS analysts and facility representatives to provide an advantage to those whose task is to defend these facilities. Evaluated facilities include: refineries, major ports, nuclear power plants and other nuclear licensees, dams, government installations, convention centers, sports stadiums, tourist venues, and public and freight transportation systems. A generalized summary of analyses of U.S. infrastructure facilities will be presented
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Use of the Homeland-Defense Operational Planning System (HOPS) for Emergency Management
The Homeland-Defense Operational Planning System (HOPS), is a new operational planning tool leveraging Lawrence Livermore National Laboratory's expertise in weapons systems and in sparse information analysis to support the defense of the U.S. homeland. HOPS provides planners with a basis to make decisions to protect against acts of terrorism, focusing on the defense of facilities critical to U.S. infrastructure. Criticality of facilities, structures, and systems is evaluated on a composite matrix of specific projected casualty, economic, and sociopolitical impact bins. Based on these criteria, significant unidentified vulnerabilities are identified and secured. To provide insight into potential successes by malevolent actors, HOPS analysts strive to base their efforts mainly on unclassified open-source data. However, more cooperation is needed between HOPS analysts and facility representatives to provide an advantage to those whose task is to defend these facilities. Evaluated facilities include: refineries, major ports, nuclear power plants and other nuclear licensees, dams, government installations, convention centers, sports stadiums, tourist venues, and public and freight transportation systems. A generalized summary of analyses of U.S. infrastructure facilities will be presented
China and the WTO dispute settlement system:from passive observer to active participant?
Since China’s accession to the World Trade Organisation (WTO) in December 2001, it has participated in a relatively small number of cases brought to the WTO Dispute Settlement Body (DSB), contrary to the many wild predictions made prior to entry. In the first few years post-accession, China seemed content to act as a passive observer, participating mainly as a third party. However, since 2006, there appears to have been a shift in attitude with China now taking a more combative stance, particularly in the past few years. This article will examine China’s participation in the WTO DSB from 2002 to date to explore whether China’s approach really has shifted from that of passive observer to that of an active participant, possible reasons to explain this transformation and what the implications of such a shift may be for other WTO Contracting Parties
Partial Genetic Turnover in Neandertals: Continuity in the East and Population Replacement in the West
Remarkably little is known about the population-level processes leading up to the extinction of the neandertal. To examine this, we use mitochondrial DNA sequences from 13 neandertal individuals, including a novel sequence from northern Spain, to examine neandertal demographic history. Our analyses indicate that recent western European neandertals (48 kyr) European neandertals. Using control region sequences, Bayesian demographic simulations provide higher support for a model of population fragmentation followed by separate demographic trajectories in subpopulations over a null model of a single stable population. The most parsimonious explanation for these results is that of a population turnover in western Europe during early Marine Isotope Stage 3, predating the arrival of anatomically modern humans in the region
Involvement in teaching improves learning in medical students: a randomized cross-over study
<p>Abstract</p> <p>Background</p> <p>Peer-assisted learning has many purported benefits including preparing students as educators, improving communication skills and reducing faculty teaching burden. But comparatively little is known about the effects of teaching on learning outcomes of peer educators in medical education.</p> <p>Methods</p> <p>One hundred and thirty-five first year medical students were randomly allocated to 11 small groups for the Gastroenterology/Hematology Course at the University of Calgary. For each of 22 sessions, two students were randomly selected from each group to be peer educators. Students were surveyed to estimate time spent preparing as peer educator versus group member. Students completed an end-of-course 94 question multiple choice exam. A paired t-test was used to compare performance on clinical presentations for which students were peer educators to those for which they were not.</p> <p>Results</p> <p>Preparation time increased from a mean (SD) of 36 (33) minutes baseline to 99 (60) minutes when peer educators (Cohen's <it>d </it>= 1.3; p < 0.001). The mean score (SD) for clinical presentations in which students were peer educators was 80.7% (11.8) compared to77.6% (6.9) for those which they were not (<it>d </it>= 0.33; <it>p </it>< 0.01).</p> <p>Conclusion</p> <p>Our results suggest that involvement in teaching small group sessions improves medical students' knowledge acquisition and retention.</p
Insights on the Evolution of Mycoparasitism from the Genome of Clonostachys rosea
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Global Panopticism: States, Corporations, and the Governance Effects of Monitoring Regimes
The Divine Comedy of Dante Alighieri Volume 3: Paradiso
One of the greatest living Italian-to-English translators, Durling has at last completed his rendition of the third and final volume of Dante's masterful literary epic, The Divine Comedy. As with the two preceding volumes, Durling's precise and powerful translation of Paradiso appears alongside the original Italian text recounting Dante's journey through heaven with the beautiful Beatrice. The end of each canto contains thorough yet succinct notes by Durling and Ronald Martinez that acquaint the reader with Dante's medieval world and his reference points. Thus the volume will appeal to the general reader as well as lovers and students of Italian literature, language, and history. While English-language translations of the Commedia abound, the accuracy and lyrical verve of Durling's translations have earned him a place as one of the all time greats. With the completion of the set, the grandeur of his accomplishment will soon be widely known.Intro -- Contents -- Abbreviations -- Introduction -- PARADISO -- CANTO 1 -- Notes to Canto 1 [RLM] -- CANTO 2 -- Notes to Canto 2 [RMD] -- CANTO 3 -- Notes to Canto 3 [RLM] -- CANTO 4 -- Notes to Canto 4 [RMD] -- CANTO 5 -- Notes to Canto 5 [RLM] -- CANTO 6 -- Notes to Canto 6 [RMD] -- CANTO 7 -- Notes to Canto 7 [RLM] -- CANTO 8 -- Notes to Canto 8 [RMD] -- CANTO 9 -- Notes to Canto 9 [RLM] -- CANTO 10 -- Notes to Canto 10 [RMD] -- CANTO 11 -- Notes to Canto 11 [RLM] -- CANTO 12 -- Notes to Canto 12 [RLM] -- CANTO 13 -- Notes to Canto 13 [RMD] -- CANTO 14 -- Notes to Canto 14 [RMD] -- CANTO 15 -- Notes to Canto 15 [RLM] -- CANTO 16 -- Notes to Canto 16 [RLM] -- CANTO 17 -- Notes to Canto 17 [RMD] -- CANTO 18 -- Notes to Canto 18 [RMD] -- CANTO 19 -- Notes to Canto 19 [RLM] -- CANTO 20 -- Notes to Canto 20 [RLM] -- CANTO 21 -- Notes to Canto 21 [RMD] -- CANTO 22 -- Notes to Canto 22 [RMD] -- CANTO 23 -- Notes to Canto 23 [RLM] -- CANTO 24 -- Notes to Canto 24 [RMD] -- CANTO 25 -- Notes to Canto 25 [RMD] -- CANTO 26 -- Notes to Canto 26 [RLM] -- CANTO 27 -- Notes to Canto 27 [RLM] -- CANTO 28 -- Notes to Canto 28 [RMD] -- CANTO 29 -- Notes to Canto 29 [RMD] -- CANTO 30 -- Notes to Canto 30 [RLM] -- CANTO 31 -- Notes to Canto 31 [RLM] -- CANTO 32 -- Notes to Canto 32 [RLM] -- CANTO 33 -- Notes to Canto 33 [RMD] -- THE NICENE CREED -- "O QUI PERPETUA MUNDUM RATIONE GUBERNAS," -- Notes to "O qui perpetua" [RMD] -- ADDITIONAL NOTES -- 1. The Figure of Beatrice (After Canto 2) -- 2. The Paradiso and the Monarchia (After Canto 6) -- 3. The Primacy of the Intellect, the Sun, and the Circling Theologians (After Canto 14) -- 4. Dante and the Liturgy (After Canto 15) -- 5. The Religious Orders in the Paradiso (After Canto 23) -- 6. The Threshold Cantos in the Comedy (After Canto 30) -- 7. The Fate of Phaethon in the Comedy (After Canto 30)8. Circle-Cross-Eagle-Scales: Images in the Paradiso -- 9. The Final Image -- 10. The Neoplatonic Background -- 11. Dante and Neoplatonism -- 12. Dante's Astrology -- 13. The Heavens and the Sciences: Convivio 2 -- 14. The Paradiso as Alpha and Omega of the Comedy -- Textual Variants -- Bibliography -- Index of Italian, Latin, and Other Foreign Words Discussed in the Notes -- Index of Passages Cited in the Notes -- Index of Proper Names Discussed in the Notes -- Index of Proper Names in the Text and TranslationOne of the greatest living Italian-to-English translators, Durling has at last completed his rendition of the third and final volume of Dante's masterful literary epic, The Divine Comedy. As with the two preceding volumes, Durling's precise and powerful translation of Paradiso appears alongside the original Italian text recounting Dante's journey through heaven with the beautiful Beatrice. The end of each canto contains thorough yet succinct notes by Durling and Ronald Martinez that acquaint the reader with Dante's medieval world and his reference points. Thus the volume will appeal to the general reader as well as lovers and students of Italian literature, language, and history. While English-language translations of the Commedia abound, the accuracy and lyrical verve of Durling's translations have earned him a place as one of the all time greats. With the completion of the set, the grandeur of his accomplishment will soon be widely known.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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