11 research outputs found
SIRANE modeling of oxides nitrogen (NOx) and ozone (O3) in the area of Agadir city, southwestern Morocco.
This work aimed to model the dispersion of the traffic emissions for the first time in the area of Agadir city (Morocco). The estimate of road emission (from vehicle counts) was performed with Circulâair software version 4.0 which is based on the European methodology Copert 4. While the dispersion modelling was performed using SIRANE model, an important tool which adopts the classic NOx photochemical process. The input data are pollutant emissions, background concentrations, meteorological parameters and building configuration data from QGIS software as well as a list of other factors such as latitude, albedo, etc.   Finally, the quality of the output results was validated by comparing observed measurements and modelled data
Glutamine Anabolism Plays a Critical Role in Pancreatic Cancer by Coupling Carbon and Nitrogen Metabolism
Glutamine is thought to play an important role in cancer cells by being deaminated via glutaminolysis to alpha-ketoglutarate (aKG) to fuel the tricarboxylic acid (TCA) cycle. Supporting this notion, aKG supplementation can restore growth/survival of glutamine-deprived cells. However, pancreatic cancers are often poorly vascularized and limited in glutamine supply, in alignment with recent concerns on the significance of glutaminolysis in pancreatic cancer. Here, we show that aKG-mediated rescue of glutamine-deprived pancreatic ductal carcinoma (PDAC) cells requires glutamate ammonia ligase (GLUL), the enzyme responsible for de novo glutamine synthesis. GLUL-deficient PDAC cells are capable of the TCA cycle but defective in aKG-coupled glutamine biosynthesis and subsequent nitrogen anabolic processes. Importantly, GLUL expression is elevated in pancreatic cancer patient samples and in mouse PDAC models. GLUL ablation suppresses the development of Kras(G12D)-driven murine PDAC. Therefore, GLUL-mediated glutamine biosynthesis couples the TCA cycle with nitrogen anabolism and plays a critical role in PDAC
POWER MOS FET MODELS FOR "SWITCHING" CIRCUITS
Un modÚle compact du transistor VDMOS de puissance, compatible avec le logiciel "SPICE2", est proposé En tant qu'applications, le transistor est "simulé" en régime de commutation sur des charges résistives et inductives et les résultats obtenus sont validés par des mesures expérimentales.A compact model of the Power VDMOS Transistor compatible with the circuit simulator "SPICE2" is described in this article. This model is applied to the simulation of switching circuit with resistive and inductive loads ; comparisons with experimental results are presented
Quantitative assessment of the saturation degree of model fine recycled concrete aggregates immersed in a filler or cement paste
\textcopyright 2018 We study water transfer between different model fine recycled concrete aggregates and fresh filler or cement paste in which they are immersed. Our aim is to introduce a spread based experimental protocol for studying the time evolution of water content in initially dry aggregates when mixed with such pastes. The procedure developed hereby is tested on three model Cement Paste Sands (CPS) prepared with different water-to-cement ratios leading to very different porosities and pore structures. The results show that water content in the CPS reaches a maximum no later than 6 min after first contact with limestone filler or cement paste then remains fairly constant afterwards. The saturation degree, i.e. ratio of the water content in the CPS to their water absorption, increases with the porosity of the CPS and remains less than one whatever the paste. The corresponding reduction of water absorption capacity in a cement paste should be taken into account during mix design of a recycled concrete
PSPICE model of the power LDMOS transistor for radio frequency applications in the 1.8 â 2.2 GHz Band
In this paper, we propose a model for the LDMOS transistor used for power
amplification in the frequencies band 1.8â2.2Â GHz dedicated to the mobile
telephony system Digital Cellular System (DCS). This model takes into account the
behaviour of each internal region of the power structure. A new representation of the
non-linear inter-electrode capacitances, drain-gate Cgd and drain-source Cds, is
proposed. The obtained model is implemented in the circuit simulator PSPICE, which
gives an overall evaluation of the transistor performances in the radio frequency
power amplification mode. This model is Maynly intended to the system designer. A
study of the power amplification in the SHF band at 2Â GHz is performed. A good
agreement between experimental and simulation results is found
The distribution of dinoflagellate cyst assemblages in recent sediments of the Oualidia Lagoon, Morocco, with a focus on toxic species
Harmful algal blooms (HABs) are becoming widely distributed and more frequent, threatening socioecosystems and human health. We determined species composition, abundance and spatial distribution of dinoflagellate cysts in the upper sediment of the Oualidia Lagoon located on the Atlantic coast of Morocco. Sediment samples were collected in 2017 at 51 stations, and environmental parameters were measured together with microphytoplankton abundance. Sediment characteristics including water percentage, organic matter content and grain size were determined. Fourteen dinoflagellate cyst morphotypes were identified, with Lingulodinium polyedrum (50%) and Gonyaulax spinifera (22%) dominating the assemblages. Total cyst densities ranged from 0 to 293 cysts gâ1 dry sediment. Cyst densities were positively correlated with water content and organic matter content and increased with decreasing sediment grain size. We revealed the presence of three neurotoxic dinoflagellate species: Alexandrium minutum, the Alexandrium tamarense species complex, and Gymnodinium catenatum. Numerous cysts had accumulated in the sediment, and, because they are likely responsible for the initiation of HABs in Oualidia Lagoon, they should be monitored
Glutamine Anabolism Plays a Critical Role in Pancreatic Cancer by Coupling Carbon and Nitrogen Metabolism
Glutamine is thought to play an important role in cancer cells by being deaminated via glutaminolysis to α-ketoglutarate (aKG) to fuel the tricarboxylic acid (TCA) cycle. Supporting this notion, aKG supplementation can restore growth/survival of glutamine-deprived cells. However, pancreatic cancers are often poorly vascularized and limited in glutamine supply, in alignment with recent concerns on the significance of glutaminolysis in pancreatic cancer. Here, we show that aKG-mediated rescue of glutamine-deprived pancreatic ductal carcinoma (PDAC) cells requires glutamate ammonia ligase (GLUL), the enzyme responsible for de novo glutamine synthesis. GLUL-deficient PDAC cells are capable of the TCA cycle but defective in aKG-coupled glutamine biosynthesis and subsequent nitrogen anabolic processes. Importantly, GLUL expression is elevated in pancreatic cancer patient samples and in mouse PDAC models. GLUL ablation suppresses the development of KrasG12D-driven murine PDAC. Therefore, GLUL-mediated glutamine biosynthesis couples the TCA cycle with nitrogen anabolism and plays a critical role in PDAC