CFD applications: The Lockheed perspective

The Numerical Aerodynamic Simulator (NAS) epitomizes the coming of age of supercomputing and opens exciting horizons in the world of numerical simulation. An overview of supercomputing at Lockheed Corporation in the area of Computational Fluid Dynamics (CFD) is presented. This overview will focus on developments and applications of CFD as an aircraft design tool and will attempt to present an assessment, withing this context, of the state-of-the-art in CFD methodology

Transonics and fighter aircraft: Challenges and opportunities for CFD

The application of computational fluid dynamics (CFD) to fighter aircraft design and development is discussed. Methodology requirements for the aerodynamic design of fighter aircraft are briefly reviewed. The state-of-the-art of computational methods for transonic flows in the light of these requirements is assessed and the techniques found most adequate for the subject application are identified. Highlights from some proof-of-feasibility Euler and Navier-Stokes computations about a complete fighter aircraft configuration are presented. Finally, critical issues and opportunities for design application of CFD are discussed

Vector meson quasinormal modes in a finite-temperature AdS/QCD model

We study the spectrum of vector mesons in a finite temperature plasma. The plasma is holographically described by a black hole AdS/QCD model. We compute the boundary retarded Green's function using AdS/CFT prescriptions. The corresponding thermal spectral functions show quasiparticle peaks at low temperatures. Then we calculate the quasinormal modes of vector mesons in the soft-wall black hole geometry and analyse their temperature and momentum dependences.Comment: 27 pages, 9 figure

Molecules and mechanisms involved in the generation and migration of cortical interneurons

The GABA (γ-aminobutyric acid)-containing interneurons of the neocortex are largely derived from the ganglionic eminences in the subpallium. Numerous studies have previously defined the migratory paths travelled by these neurons from their origins to their destinations in the cortex. We review here results of studies that have identified many of the genes expressed in the subpallium that are involved in the specification of the subtypes of cortical interneurons, and the numerous transcription factors, motogenic factors and guidance molecules that are involved in their migration

The constant-velocity highly collimated outflows of the planetary nebula He 2-90

We present high-dispersion echelle spectroscopic observations and a narrow-band [N II] image of the remarkable jet-like features of He 2-90. They are detected in the echelle spectra in the H-alpha and [N II] lines but not in other nebular lines. The [N II]/H-alpha ratio is uniformly high, ~1. The observed kinematics reveals bipolar collimated outflows in the jet-like features and shows that the southeast (northwest) component expands towards (away from) the observer at a remarkably constant line-of-sight velocity, 26.0+-0.5 km/s. The observed expansion velocity and the opening angle of the jet-like features are used to estimate an inclination angle of ~5 degrees with respect to the sky plane and a space expansion velocity of ~290 km/s. The spectrum of the bright central nebula reveals a profusion of Fe lines and extended wings of the H-alpha line, similar to those seen in symbiotic stars and some young planetary nebulae that are presumed to host a mass-exchanging binary system. If this is the case for He 2-90, the constant velocity and direction of the jets require a very stable dynamic system against precession and warping.Comment: 8 pages (emulate ApJ), 5 figure, 1 tabl

Radiales time series: 25 years building monitoring and analytical capacities in the Iberian shelf

The RADIALES program has been monitoring shelf waters in Spain for the last 25 years. This is the oldest field program for multidisciplinary marine research addressing long term variability issues at ecosystem level. Core observations include ship-based hydrographic, biogeochemical and plankton observations at monthly frequency in several oceanographic sections along the Iberian shelf. These observations are complemented with buoy and satellite observations and all these data are used to validate hydrographic and ecological models of plankton at local and regional scales. From the first series initiated in the northwestern shelf other programs extended the observations to the Mediterranean and off shelf waters using the same approach. The success of RADIALES extends beyond pure scientific knowledge, as the expertise gathered with the program has been applied to solve multiple environmental issues, from fisheries and pollution to global change. The program is also instrumental for educational purposes, allowing the specialization of students and technicians. Thanks to a basal funding provided by the Instituto Español de Oceanografía, the program currently obtains more than 60% of its annual budget from competitive calls, as it offers an unique platform for coastal research. Among the results of this program are 400 publications, including peer-review papers, 24 Thesis and 54 scientific reports. The RADIALES data are freely distributed to national and international users as a contribution to the development of cost-effective ocean research and marine servicesIEO (RADIALES

Evaluation of inbred lines, commercial materials, and two maize populations for aluminum tolerance

Avaliação da tolerância a Al (4,5 mg/l) de 39 linhagens, 98 materiais comerciais, 167 progênies de uma população IAC-Maya e de 466 progênies de uma população IAC-Taiuba de milho (Zea mays L), usando-se a técnica de solução nutritiva. Foram utilizados os seguintes índices: ICR (índice de crescimento da radícula), determinado através da multiplicação dos índices CRR  (comprimento relativo da radícula) e CRRSML (comprimento relativo da raiz secundária mais longa), e CLR (comprimento líquido da radícula) calculado pela diferença entre os valores de CR (comprimento da radícula) obtidos no inicio e fim do período de crescimento das plantas em presença de alumínio. Os índices CRR e CRRSML foram 4erivados da relação obtida entre os valores obtidos na presença e ausência de Al. As linhagens e as progênies da população IAC-Maya foram avaliadas através do ICR, enquanto os demais o foram pelo índice CLR. Os materiais controles foram IAC HS1227 (tolerante a Al) e IAC HS7777 (sensível a Al). O método de solução nutritiva foi eficiente na diferenciação da tolerância a Al dentre os materiais testados, evidenciando a ocorrência de ampla variabilidade genética para essa característica. As seguintes linhagens e materiais comerciais apresentaram tolerância ao Al (4,5 mg/l): Porto Rico 70.D.2, Ip 48-5-3, Ip 365-4-1, IA 2992-3-1-2-3, Viç 3-2-3-30-V-6,490,519, 532, 535-2 e 820 (linhagens) e AG 82, AG 260, AGROMEM 1022, ASGROW 1255, DINA 03 5, DINA 47, IAC Hmd 7974,SS 1243 e UNICAMP 720 (materiais comerciais).The evaluation of 39 inbred lines, 98 commercial materials, 167 progenies from, an IAC-Maya population, and 466 progenies from an IAC-Taiuba population of maize (Zea mays L.) for Al tolerance in nutrient solutions was carried out. The following root characteristics were use: CRI (growth radicle index), determined by multiplying RRL (relative radicle length) and RLLSR (relative length of the longest secondary root), and NRL (net radicle length) estimated by the difference between the measurements of RL (radicle length) obtained at the beginning and at the end of the growth period in Al-stressed nutrient solutions. Both indices RRL and RLLSR were determined by dividing the values obtained in solutions with and no added Al. The characteristic GRI was used to evaluate the inbred lines and the IAC-Maya populations, while NRL was used for the commercial materials. The control materials were IAC HS 1227 (Al tolerant) and IAC HS 7777 (Al susceptible). The nutrient solution technique was efficient to differentiate Al tolerance among the maize genotypes tested. A wide genetic variability was found regarding the Al tolerance trait among the maize genotypes tested. The following maize inbred lines and commercial materials were tolerant to Al (4,5 mg/l): Porto Rico 70.D.2, Ip 48-5-3, Ip 365-4-1, IA 2992-3-1-2-3, Viç 3-2-3-30-V-6, 490, 519, 532, 535-2, and 820 (inbred lines) and AG 82, AO 260, AGROMEM 1022, ASGROW 1255, DINA 03S, DINA 47, IAC Hmd 7974, SS 1243, and UNICAMP 720 (commercial materials)

Bis(hydrosulfido)-bridged dinuclear rhodium(I) complexes as a platform for the synthesis of trinuclear sulfido aggregates with the core [MRh2(μ3-S2)] (M = Rh, Ir, Pd, Pt, Ru)

The reaction of [Rh(μ-SH)(CO)(PPh3)]2 or [Rh(μ-SH){P(OPh)3}2]2 with [Cp*MCl2]2 (M = Rh, Ir) in the presence of NEt3 afforded the Rh3 and IrRh2 sulfido-bridged compounds [Cp*M(μ3-S)2Rh2(CO)2(PPh3)2] (M = Rh, 1; Ir, 2) and [Cp*Rh(μ3-S)2Rh2{P(OPh)3}4] (3). The reaction with [MCl2(cod)] (M = Pd, Pt), cis-[PtCl2(PPh3)2] or [(η6-C6H6)RuCl2]2 under the same experimental conditions gave [(cod)M(μ3-S)2Rh2{P(OPh)3}4] (M = Pd, 6; Pt, 7), [(cod)M(μ3-S)2Rh2(CO)2(PPh3)2] (M = Pd, 8; Pt, 9), [(PPh3)2Pt(μ3-S)2Rh2(CO)2(PPh3)2] (10) and [(η6-C6H6)Ru(μ3-S)2Rh2(CO)2(PPh3)2] (12), with PdRh2, PtRh2 and RuRh2 trimetallic cores. The aggregates derived from [Rh(μ-SH)(CO)(PPh3)]2 were isolated as a mixture of trans and cis isomers in which the trans isomer predominates. The reaction of [Rh(μ-SH){P(OPh)3}2]2 with 2 equiv. of n-BuLi at 253 K followed by addition of [Cp*IrCl2]2 gave [Cp*Ir(μ3-S)2Rh2{P(OPh)3}4] (4) and [Cp*2ClIr2(μ3-S)2Rh{P(OPh)3}2] (5) in a 3:2 ratio. The RuRh2 compound [(η6-C6H6)Ru(μ3-S)2Rh2{P(OPh)3}4] (11) was prepared similarly from [Rh(μ-SH){P(OPh)3}2]2 and [(η6-C6H6)RuCl2]2 using n-BuLi as a deprotonating agent. The molecular structures of compounds 3, 6, 7, 9 and 11 have been determined by X-ray analysis. The trinuclear complexes exhibit an asymmetric triangular metal core with two triply bridging sulfido ligands resulting in a distorted trigonal-bipyramidal M3(μ3-S)2 heterometallic metal–sulfur core.Financial support from the Ministerio de Ciencia e Innovación (MICINN/FEDER) of Spain (Project CTQ2010-15221), the Diputación General de Aragón (E07), and CONSOLIDER INGENIO-2010, Projects MULTICAT (CSD2009-00050) and Factoría de Cristalización (CSD2006-0015) is gratefully acknowledged.Peer Reviewe

UV-R mitigation strategies in encapsulated embryos of the intertidal gastropod Acanthina monodon: A way to compensate for lack of parental care

Intracapsular embryonic development in the intertidal zone exposes embryos to various stress sources characteristic of this environment, including UV-R. They require defensive mechanisms to mitigate its adverse effects. The presence of total carotenoids (TC), and mycosporine-like amino acids (MAAs) was studied in adults, in encapsulated embryos, and in the egg capsule walls of the intertidal gastropod Acanthina monodon. Oxygen consumption rates (OCR) were determined in encapsulated and excapsulated embryos exposed to photosynthetically active radiation (PAR) and PAR + UV-A + UV-B to understand if the capsule wall is a protective structure for encapsulated embryos. The results showed the presence of TC in adult pedal and gonad tissues, and in all encapsulated stages. MAAs were not detected. The physical structure of the capsule wall retained most wavelengths, being particularly efficient in the UV-B range. Excapsulated embryos exposed to PAR + UV-A + UV-B radiation increased its OCR compared to encapsulated embryos, indicating the protective character of the capsule wall.Fil: Cubillos, Victor M.. Universidad Austral de Chile; ChileFil: Salas Yanquin, Luis P.. Universidad Austral de Chile; ChileFil: Buchner Miranda, Joseline. Universidad Austral de Chile; ChileFil: Ramirez, Felipe. Universidad Austral de Chile; ChileFil: Zabala, Maria Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; ArgentinaFil: Averbuj, Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; ArgentinaFil: Marquez, Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; Argentina. Universidad Nacional de la Patagonia. Facultad de Ciencias Naturales. Sede Puerto Madryn; ArgentinaFil: Jaramillo, Hans. Universidad Austral de Chile; ChileFil: Chaparro, Oscar R.. Universidad Austral de Chile; Chil