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Sediment fill in the Middle America Trench inferred from gravity anomalies  [PDF]
Marina Manea,Vlad C. Manea,Vladimir Kostoglodov
Geofísica internacional , 2003,
Abstract: A sequence of free-air gravity anomaly profiles across the Middle America Trench are used to model the sediment fill of unconsolidated pelagic and hemipelagic sediment facies, and partially altered bedrock material. The shift of the free-air forearc low from the bathymetric minimum in the trench is used to estimate the amount of low-density sediment. The gravity effect of the fill is relatively small, suggesting that the dominant processes in the Middle America trench are sediment subduction and scraping of unconsolidated pelagic sediments from the top of the subducting oceanic plate. The sediment volume in the trench tends to increase southward from Jalisco to Oaxaca. In the Guatemala basin this tendency is less clear. There is some correlation between the amount of fresh sediment fill and the convergence rate at the trench, except for the profiles with an extensive terrigenous sediment contribution or the areas of subduction of prominent bathymetric features.
Indentation tectonics in the accretionary wedge of middle Manila Trench
LI Jiabiao,JIN Xianglong,RUAN Aiguo,WU Shimin,WU Ziyin & LIU Jianhua Key Lab of Submarine Geosciences,State Oceanic Administration,Hangzhou,China,College of Sciences,Zhejiang University,Hangzhou,China,South China Sea Institute of Oceanology,Chinese Academy of Sci- ences,Guangzhou,China,

科学通报(英文版) , 2004,
Abstract: Based on the multibeam morpho-tectonic analysis of the Manila Trench accretionary wedge and its indentation tectonics and the contrasting researches with other geological and geophysical data, three tectonic zones of the wedge are established, faulting features, tectonic distri- bution and stress mechanism for the indentation tectonics are analyzed, oblique subduction along Manila Trench with convergent stress of NW55° is presented, and the relation- ship of the ceasing of Eastern Subbasin spreading of South China Sea Basin to the formation of subduction zone of Ma- nila Trench is discussed. By the model analysis and regional research, it is found that the seamount subduction along Ma- nila Trench does not lead to the erosion of the accretionary wedge and the oblique subduction actually is a NWW- trending obduction of Luzon micro-plate that results from the NWW-trending displacement of the Philippine Sea plate.
Comparative Studies on the Primary and Middle School Teachers’ Employment Systems Between China and America  [cached]
Canadian Social Science , 2012, DOI: 10.3968/2718
Abstract: Teachers’ Employment System is an important personnel reform in Chinese schools which shows a positive impact on faculty team-building in primary schools and middle schools. Due to short-term reform and lack of historical experience in the primary and middle school teachers’ employment system in China, there are still many problems to solve in practice. This paper plans to fi nd out these problems to help future reform on faculty employment reform in China by fi nding out the problems existing in the teachers’ employment system in primary schools and secondary schools and comparing Chinese primary and middle school teachers’ employment systems with American primary and middle school teachers’ employment systems. Key words: China; America; Primary and middle school; Teachers’ employment system
Floristic composition and comparison of middle Eocene to late Eocene and Oligocene floras in North America  [PDF]
Devore M L,Pigg K B
Bulletin of Geosciences , 2010, DOI: 10.3140/bull.geosci.1135
Abstract: In comparison to the early and middle Eocene, the late Eocene and particularly the Oligocene floral record is sparse in North America. Changing tectonic, environmental and climatic conditions during these times resulted in the development of fewer depositional systems favorable for fossil preservation. Floras are known from the Southeast, the Pacific Northwest and the Rocky Mountains. Each area has a distinct geological history that shaped both the vegetation adjacent to sites of deposition as well as the depositional environments themselves. The floristic change from middle to late Eocene, and then to Oligocene reflects a changing paleoclimate from the thermal maximum to cooler and drier conditions in the late Paleogene. In the present paper, major middle, and then late Eocene and finally Oligocene floras of North America are summarized, with an emphasis on their regional geology, depositional setting, paleoclimate and significant floral elements. The North American occurrences of coryphoid palms (Sabal) and cycads are reviewed in relationship to their biogeographic history. Finally, we suggest several directions for future research that will further illuminate the floristic changes from middle, to late Eocene and Oligocene that occurred in North America.
Identifying important breast cancer control strategies in Asia, Latin America and the Middle East/North Africa
John FP Bridges, Benjamin O Anderson, Antonio C Buzaid, Abdul R Jazieh, Louis W Niessen, Barri M Blauvelt, David R Buchanan
BMC Health Services Research , 2011, DOI: 10.1186/1472-6963-11-227
Abstract: To identify and compare the need for breast cancer control strategies in Asia, Latin America and the Middle East/North Africa and to develop a common framework to guide the development of national breast cancer control strategies.Data were derived from open-ended, semi-structured interviews conducted in 2007 with 221 clinicians, policy makers, and patient advocates; stratified across Asia (n = 97), Latin America (n = 46), the Middle East/North Africa (ME/NA) (n = 39) and Australia and Canada (n = 39). Respondents were identified using purposive and snowballing sampling. Interpretation of the data utilized interpretive phenomenological analysis where transcripts and field notes were coded and analyzed and common themes were identified. Analysis of regional variation was conducted based on the frequency of discussion and the writing of the manuscript followed the RATS guidelines.Analysis revealed four major themes that form the foundation for developing national breast cancer control strategies: 1) building capacity; 2) developing evidence; 3) removing barriers; and 4) promoting advocacy - each specified across five sub-ordinate dimensions. The propensity to discuss most dimensions was similar across regions, but managing advocacy was discussed more frequently (p = 0.004) and organized advocacy was discussed less frequently (p < 0.001) in Australia and Canada.This unique research identified common themes for the development of breast cancer control strategies, grounded in the experience of local practitioners, policy makers and advocacy leaders across diverse regions. Future research should be aimed at gathering a wider array of experiences, including those of patients.Breast cancer ranks as the fifth cause of death from cancer overall, but it is still the most frequent cause of cancer death in women in both developing and developed regions [1]. As such, breast cancer control has become a global imperative, yet global inequities persist [2,3]. Many lesser developed co
Projecting Extreme Changes in Summer Rainfall in South America by the Middle of the 21st Century  [PDF]
Paula Andrea M. Fonseca, José Augusto P. Veiga, Francis Wagner S. Correia, Adriane L. Brito, M?nica R. Queiroz, André A. Lyra, Sin Chan Chou
Atmospheric and Climate Sciences (ACS) , 2014, DOI: 10.4236/acs.2014.44067

Extreme rainfall events can be considered a natural manifestation of the environment in which they are embedded and foreknowledge about their future behavior is very important, especially for decision makers. In this context, we aimed to explore the future behavior of extreme rainfall intensity through numerical simulations with the ETA model. The model was forced with a scenario of high greenhouse gas emissions for the middle of the 21st Century as described for A1B emission scenario. We detailed the main changes in accumulated rainfall produced by heavy events, very heavy events and rare events over a broad area of South America with a focus on the tropical sector. The methodology applied here is capable of separating extreme events and establishing the quantity of rainfall yielded by them. We have found that in the near future (2041-2050) rare events will tend to increase over the Amazon basin, followed by reductions in heavy and very heavy events. Conversely, heavy, very heavy and rare events are expected to decline over north-east Brazil. Furthermore, increases were found for heavy, very heavy and rare events over southern Brazil.

Minimal redefinition of the OSV ensemble  [PDF]
Shahrokh Parvizi,Alireza Tavanfar
Mathematics , 2005, DOI: 10.1063/1.2393149
Abstract: In the interesting conjecture, Z_{BH} = |Z_{top}|^2, proposed by Ooguri, Strominger and Vafa (OSV), the black hole ensemble is a mixed ensemble and the resulting degeneracy of states, as obtained from the ensemble inverse-Laplace integration, suffers from prefactors which do not respect the electric-magnetic duality. One idea to overcome this deficiency, as claimed recently, is imposing nontrivial measures for the ensemble sum. We address this problem and upon a redefinition of the OSV ensemble whose variables are as numerous as the electric potentials, show that for restoring the symmetry no non-Euclidean measure is needful. In detail, we rewrite the OSV free energy as a function of new variables which are combinations of the electric-potentials and the black hole charges. Subsequently the Legendre transformation which bridges between the entropy and the black hole free energy in terms of these variables, points to a generalized ensemble. In this context, we will consider all the cases of relevance: small and large black holes, with or without D_6-brane charge. For the case of vanishing D_6-brane charge, the new ensemble is pure canonical and the electric-magnetic duality is restored exactly, leading to proper results for the black hole degeneracy of states. For more general cases, the construction still works well as far as the violation of the duality by the corresponding OSV result is restricted to a prefactor. In a concrete example we shall show that for black holes with non-vanishing D_6-brane charge, there are cases where the duality violation goes beyond this restriction, thus imposing non-trivial measures is incapable of restoring the duality. This observation signals for a deeper modification in the OSV proposal.
A simulation study on a novel trench SJ IGBT
Trench SJ IGBT 的仿真研究

Wang Bo,Tan Jingfei,Zhang Wenliang,Chu Weili,Zhu Yangjun,

半导体学报 , 2012,
Abstract: An overall analysis of the trench superjunction insulated gate bipolar transistor (SJ IGBT) is presented and a detailed comparison between a trench SJ IGBT and a trench field stop IGBT is made by simulating with Sentaurus TCAD. More specifically, simulation results show that the trench SJ IGBT exhibits a breakdown voltage that is raised by 100 V while the on-state voltage is reduced by 0.2 V. At the same time, the turn-off loss is decreased by 50%. The effect of charge imbalance on the static and dynamic characteristics of the trench SJ IGBT is studied, and the trade-off between parameters and their sensitivity versus charge imbalance is discussed.
Field Redefinition Invariance and "Extra Terms"  [PDF]
K. M. Apfeldorf,C. R. Ordonez
Physics , 1994, DOI: 10.1016/0550-3213(96)00451-8
Abstract: We investigate the issue of coordinate redefinition invariance by carefully performing nonlinear transformations in the discretized quantum mechanical path integral. By resorting to hamiltonian path integral methods, we provide the first complete derivation of the extra terms (beyond the usual jacobian term) which arises in the action when a nonlinear transformation is made. We comment on possible connections with the renormalization group, by showing that these extra terms may emerge from a ``blocking" procedure. Finally, by performing field redefinitions before and after dimensional reduction of a two dimensional field theory, we derive an explicit form fo an extra term appearing in a field theory.
Systematic Review of Breast Cancer Biology in Developing Countries (Part 1): Africa, the Middle East, Eastern Europe, Mexico, the Caribbean and South America  [PDF]
Riyaz Bhikoo,Sanket Srinivasa,Tzu-Chieh Yu,David Moss,Andrew G Hill
Cancers , 2011, DOI: 10.3390/cancers3022358
Abstract: There has been no systematic appraisal of ethnicity-based variations in breast cancer (BC) biology amongst women from developing countries. A qualitative systematic review was conducted of breast cancer size, stage, grade, histological type, extra-mammary involvement, hormone receptor status as well as patient demographics. This review includes patients from Africa, the Middle East, Eastern Europe, Mexico, the Caribbean and South America. BC in these regions present at an earlier age with large aggressive tumours. Distant metastases are frequently present at the time of diagnosis. African women have a higher frequency of triple negative tumours. Over half of Middle Eastern women have lymph node involvement at the time of diagnosis. Despite experiencing a lower incidence compared to the Ashkenazi Jewish population, Palestinian women have poorer five-year survival outcomes. The majority of women from Mexico and South America have stage two or three disease whilst over sixty percent of women from Eastern Europe have either stage one or stage two disease. The biological characteristics of BC in the Caribbean cannot be fully assessed due to a paucity of data from the region. BC amongst the developing world is characterised by an early peak age of onset with aggressive biological characteristics. Strategies that improve breast cancer awareness, address amenable risk factors and improve early detection are essential.
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