Numerical framework for transcritical real-fluid reacting flow simulations using the flamelet progress variable approach

An extension to the classical FPV model is developed for transcritical real-fluid combustion simulations in the context of finite volume, fully compressible, explicit solvers. A double-flux model is developed for transcritical flows to eliminate the spurious pressure oscillations. A hybrid scheme with entropy-stable flux correction is formulated to robustly represent large density ratios. The thermodynamics for ideal-gas values is modeled by a linearized specific heat ratio model. Parameters needed for the cubic EoS are pre-tabulated for the evaluation of departure functions and a quadratic expression is used to recover the attraction parameter. The novelty of the proposed approach lies in the ability to account for pressure and temperature variations from the baseline table. Cryogenic LOX/GH2 mixing and reacting cases are performed to demonstrate the capability of the proposed approach in multidimensional simulations. The proposed combustion model and numerical schemes are directly applicable for LES simulations of real applications under transcritical conditions.Comment: 55th AIAA Aerospace Sciences Meeting, Dallas, T

Taxa de corte sustentável para manejo das florestas tropicais.

Existe uma grande lacuna dos planos de manejo de florestas tropicais com relação à intensidade de extração e às taxas de corte, usualmente sendo definidas de forma arbitrária. Este trabalho visa definir intensidades de corte diferenciadas para grupos de espécies arbóreas comerciais, com diferentes ritmos de crescimento, por unidade de produção, no estado do Amazonas. Utilizou-se o incremento periódico anual percentual em volume, de 26 espécies arbóreas, obtido de parcelas permanentes. O incremento periódico anual, percentual em volume, para efeito diferenciador, considerou 1% como diferença limite. Foram identificadas três intensidades de corte, para as classes comerciais: 24,4% (grupo I), 35,4% (grupo II) e 42,4% (grupo III). Considerando a exploração total sustentável por hectare, para as 26 espécies, seria de 11,5 m³ha-1 com intensidade de corte de 37%. O procedimento de cálculo é simples e pode ser utilizado pelos órgãos fiscalizadores, certificadores ou legisladores como balizador do ciclo de corte e taxa de corte

Taxa de corte sustentável para manejo das florestas tropicais.

Existe uma grande lacuna dos planos de manejo de florestas tropicais com relação à intensidade de extração e às taxas de corte, usualmente sendo definidas de forma arbitrária. Este trabalho visa definir intensidades de corte diferenciadas para grupos de espécies arbóreas comerciais, com diferentes ritmos de crescimento, por unidade de produção, no estado do Amazonas. Utilizou-se o incremento periódico anual percentual em volume, de 26 espécies arbóreas, obtido de parcelas permanentes. O incremento periódico anual, percentual em volume, para efeito diferenciador, considerou 1% como diferença limite. Foram identificadas três intensidades de corte, para as classes comerciais: 24,4% (grupo I), 35,4% (grupo II) e 42,4% (grupo III). Considerando a exploração total sustentável por hectare, para as 26 espécies, seria de 11,5 m³ha-1 com intensidade de corte de 37%. O procedimento de cálculo é simples e pode ser utilizado pelos órgãos fiscalizadores, certificadores ou legisladores como balizador do ciclo de corte e taxa de corte

Remote nuclear screening system for hostile environments

A remote measurement system has been constructed for in situ gamma and beta isotopic characterization of highly radioactive nuclear material in hostile environments. A small collimated, planar CdZnTe detector is used for gamma-ray spectroscopy. Spectral resolution of 2% full width at half maximum at 662 kiloelectronvolts has been obtained remotely using rise time compensation and limited pulse shape discrimination, Isotopc measurement of high-energy beta emitters was accomplished with a ruggedized, deeply depleted, surface barrier silicon dictator. The primary function of the remote nuclear screening system is to provide fast qualitative and quantitative isotopic assessment of high-level radioactive material

Party-group relations in new southern European democracies in the crisis era

UID/CPO/04627/2013 PTDC/IVC-CPO/1864/2014publishersversionpublishe

Depleted 15N in hydrolysable-N of arctic soils and its implication for mycorrhizal fungi–plant interaction

Author Posting. © The Author(s), 2009. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in Biogeochemistry 97 (2009): 183-194, doi:10.1007/s10533-009-9365-1.Uptake of nitrogen (N) via root-mycorrhizal associations accounts for a significant portion of total N supply to many vascular plants. Using stable isotope ratios (δ15N) and the mass balance among N pools of plants, fungal tissues, and soils, a number of efforts have been made in recent years to quantify the flux of N from mycorrhizal fungi to host plants. Current estimates of this flux for arctic tundra ecosystems rely on the untested assumption that the δ15N of labile organic N taken up by the fungi is approximately the same as the δ15N of bulk soil. We report here hydrolysable amino acids are more depleted in 15N relative to hydrolysable ammonium and amino sugars in arctic tundra soils near Toolik Lake, Alaska, USA. We demonstrate, using a case study, that recognizing the depletion in 15N for hydrolysable amino acids (δ15N = -5.6 ‰ on average) would alter recent estimates of N flux between mycorrhizal fungi and host plants in an arctic tundra ecosystem.This study was funded by NSF-DEB-0423385and NSF-DEB 0444592. Additional support was provided by Arctic Long Term Ecological Research program, funded by National Science Foundation, Division of Environmental Biology

Long-term efficacy, tolerability and overall survival in patients with platinum-sensitive, recurrent high-grade serous ovarian cancer treated with maintenance olaparib capsules following response to chemotherapy

BACKGROUND: In Study 19, maintenance monotherapy with olaparib significantly prolonged progression-free survival vs placebo in patients with platinum-sensitive, recurrent high-grade serous ovarian cancer. METHODS: Study 19 was a randomised, placebo-controlled, Phase II trial enrolling 265 patients who had received at least two platinum-based chemotherapy regimens and were in complete or partial response to their most recent regimen. Patients were randomised to olaparib (capsules; 400 mg bid) or placebo. We present long-term safety and final mature overall survival (OS; 79% maturity) data, from the last data cut-off (9 May 2016). RESULTS: Thirty-two patients (24%) received maintenance olaparib for over 2 years; 15 (11%) did so for over 6 years. No new tolerability signals were identified with long-term treatment and adverse events were generally low grade. The incidence of discontinuations due to adverse events was low (6%). An apparent OS advantage was observed with olaparib vs placebo (hazard ratio 0.73, 95% confidence interval 0.55‒0.95, P = 0.02138) irrespective of BRCA1/2 mutation status, although the predefined threshold for statistical significance was not met. CONCLUSIONS: Study 19 showed a favourable final OS result irrespective of BRCA1/2 mutation status and unprecedented long-term benefit with maintenance olaparib for a subset of platinum-sensitive, recurrent ovarian cancer patients

AID-Targeting and Hypermutation of Non-Immunoglobulin Genes Does Not Correlate with Proximity to Immunoglobulin Genes in Germinal Center B Cells

Upon activation, B cells divide, form a germinal center, and express the activation induced deaminase (AID), an enzyme that triggers somatic hypermutation of the variable regions of immunoglobulin (Ig) loci. Recent evidence indicates that at least 25% of expressed genes in germinal center B cells are mutated or deaminated by AID. One of the most deaminated genes, c-Myc, frequently appears as a translocation partner with the Ig heavy chain gene (Igh) in mouse plasmacytomas and human Burkitt's lymphomas. This indicates that the two genes or their double-strand break ends come into close proximity at a biologically relevant frequency. However, the proximity of c-Myc and Igh has never been measured in germinal center B cells, where many such translocations are thought to occur. We hypothesized that in germinal center B cells, not only is c-Myc near Igh, but other mutating non-Ig genes are deaminated by AID because they are near Ig genes, the primary targets of AID. We tested this “collateral damage” model using 3D-fluorescence in situ hybridization (3D-FISH) to measure the distance from non-Ig genes to Ig genes in germinal center B cells. We also made mice transgenic for human MYC and measured expression and mutation of the transgenes. We found that there is no correlation between proximity to Ig genes and levels of AID targeting or gene mutation, and that c-Myc was not closer to Igh than were other non-Ig genes. In addition, the human MYC transgenes did not accumulate mutations and were not deaminated by AID. We conclude that proximity to Ig loci is unlikely to be a major determinant of AID targeting or mutation of non-Ig genes, and that the MYC transgenes are either missing important regulatory elements that allow mutation or are unable to mutate because their new nuclear position is not conducive to AID deamination