Development of a transformation system for sorghum (Sorghum bicolor L.)

Sorghum (Sorghum bicolor (L.) Moench) is the world’s fifth major cereal crop and holds importance as a construction material, food and fodder source. More recently, the potential of this plant as a biofuel source has been noted. Despite its agronomic importance, the use of sorghum production is being constrained by both biotic and abiotic factors. These challenges could be addressed by the use of genetic engineering strategies to complement conventional breeding techniques. However, sorghum is one of the most recalcitrant crops for genetic modification with the lack of an efficient tissue culture system being amongst the chief reasons. Therefore, the aim of this study was to develop an efficient tissue culture system for establishing regenerable embryogenic cell lines, micropropagation and acclimatisation for Sorghum bicolor and use this to optimise parameters for genetic transformation via Agrobacterium-mediated transformation and microprojectile bombardment. Using five different sorghum cultivars, SA281, 296B, SC49, Wray and Rio, numerous parameters were investigated in an attempt to establish an efficient and reproducible tissue culture and transformation system. Using immature embryos (IEs) as explants, regenerable embryogenic cell lines (ECLs) could only be established from cultivars SA281 and 296B. Large amounts of phenolics were produced from IEs of cultivars, SC49, Wary and Rio, and these compounds severely hindered callus formation and development. Cultivar SA281 also produced phenolics during regeneration. Attempts to suppress the production of these compounds in cultivars SA281 and SC49 using activated charcoal, PVP, ascorbic acid, citric acid and liquid filter paper bridge methods were either ineffective or had a detrimental effect on embryogenic callus formation, development and regeneration. Immature embryos sourced during summer were found to be far more responsive in vitro than those sourced during winter. In an attempt to overcome this problem, IEs were sourced from sorghum grown under summer conditions in either a temperature controlled glasshouse or a growth chamber. However, the performance of these explants was still inferior to that of natural summer-sourced explants. Leaf whorls, mature embryos, shoot tips and leaf primordia were found to be unsuitable as explants for establishing ECLs in sorghum cultivars SA281 and 296B. Using the florets of immature inflorescences (IFs) as explants, however, ECLs were established and regenerated for these cultivars, as well as for cultivar Tx430, using callus induction media, SCIM, and regeneration media, VWRM. The best in vitro responses, from the largest possible sized IFs, were obtained using plants at the FL-2 stage (where the last fully opened leaf was two leaves away from the flag leaf). Immature inflorescences could be stored at 25oC for up to three days without affecting their in vitro responses. Compared to IEs, the IFs were more robust in tissue culture and showed responses which were season and growth condition independent. A micropropagation protocol for sorghum was developed in this study. The optimum plant growth regulator (PGR) combination for the micropropagation of in vitro regenerated plantlets was found to be 1.0 mg/L BAP in combination with 0.5 mg/L NAA. With this protocol, cultivars 296B and SA281 produced an average of 57 and 13 off-shoots per plantlet, respectively. The plantlets were successfully acclimatised and developed into phenotypically normal plants that set seeds. A simplified acclimatisation protocol for in vitro regenerated plantlets was also developed. This protocol involved deflasking in vitro plantlets with at least 2 fully-opened healthy leaves and at least 3 roots longer than 1.5 cm, washing the media from the roots with running tap water, planting in 100 mm pots and placing in plastic trays covered with a clear plastic bag in a plant growth chamber. After seven days, the corners of the plastic cover were opened and the bags were completely removed after 10 days. All plantlets were successfully acclimatised regardless of whether 1:1 perlite:potting mix, potting mix, UC mix or vermiculite were used as potting substrates. Parameters were optimised for Agrobacterium-mediated transformation (AMT) of cultivars SA281, 296B and Tx430. The optimal conditions were the use of Agrobacterium strain LBA4404 at an inoculum density of 0.5 OD600nm, heat shock at 43oC for 3 min, use of the surfactant Pluronic F-68 (0.02% w/v) in the inoculation media with a pH of 5.2 and a 3 day co-cultivation period in dark at 22oC. Using these parameters, high frequencies of transient GFP expression was observed in IEs precultured on callus initiation media for 1-7 days as well as in four weeks old IE- and IF-derived callus. Cultivar SA281 appeared very sensitive to Agrobacterium since all tissue turned necrotic within two weeks post-exposure. For cultivar 296B, GFP expression was observed up to 20 days post co-cultivation but no stably transformed plants were regenerated. Using cultivar Tx430, GFP was expressed for up to 50 days post co-cultivation. Although no stably transformed plants of this cultivar were regenerated, this was most likely due to the use of unsuitable regeneration media. Parameters were optimised for transformation by particle bombardment (PB) of cultivars SA281, 296B and Tx430. The optimal conditions were use of 3-7 days old IEs and 4 weeks old IF callus, 4 hour pre- and post-bombardment osmoticum treatment, use of 0.6 µm gold microparticles, helium pressure of 1500 kPa and target distance of 15 cm. Using these parameters for PB, transient GFP expression was observed for up to 14, 30 and 50 days for cultivars SA281, 296B and Tx430, respectively. Further, the use of PB resulted in less tissue necrosis compared to AMT for the respective cultivars. Despite the presence of transient GFP expression, no stably transformed plants were regenerated. The establishment of regenerable ECLs and the optimization of AMT and PB parameters in this study provides a platform for future efforts to develop an efficient transformation protocol for sorghum. The development of GM sorghum will be an important step towards improving its agronomic properties as well as its exploitation for biofuel production.

Sensing and control for a small-size helicopter

This paper details the progress to date, toward developing a small autonomous helicopter. We describe system architecture, avionics, visual state estimation, custom IMU design, aircraft modelling, as well as various linear and neuro/fuzzy control algorithms. Experimental results are presented for state estimation using fused stereo vision and IMU data, heading control, and attitude control. FAM attitude and velocity controllers have been shown to be effective in simulation.

La norme du corps hybride : Une éthique de la reconstruction et de l'amélioration du corps humain en chirurgie

Aujourd'hui, techniques et technologies interagissent avec le corps humain et donnent aux personnes la possibilité de reconstruire leur corps, mais aussi de l'améliorer et de l'augmenter. L'hybridation est un processus technologique visant à compenser les défaillances humaines. L'augmentation de la puissance d'être est exaltée (santé, sexualité, performance, jeunesse), pourtant son accès n'est pas pour tous. Ce livre propose de démêler les différentes représentations du corps hybride et les projets qui les sous-tendent.

Performance analysis of a slotted-ALOHA protocol on a capture channel with fading

We consider the slotted ALOHA protocol on a channel with a capture effect. There are M , i packets are transmitted, then the probability of a successful reception of a packet is q(i). This model contains the CDMA protocols as special cases. We obtain sufficient rate conditions, which are close to necessary for stability of the system, when the arrival streams are stationary ergodic. Under the same rate conditions, for general regenerative arrival streams, we obtain the rates of convergence to stationarity, finiteness of stationary moments and various functional limit theorems. Our arrival streams contain all the traffic models suggested in the recent literature, including the ones which display long range dependence. We also obtain bounds on the stationary moments of waiting times which can be tight under realistic conditions. Finally, we obtain several results on the transient performance of the system, e.g., first time to overflow and the limits of the overflow process. We also extend the above results to the case of a capture channel exhibiting Markov modulated fading. Most of our results and proofs will be shown to hold also for the slotted ALOHA protocol without capture.

Profiling of late Tertiary-early Quaternary surface in the lower reaches of Narmada valley using microtremors

In this paper, we propose the first approximation for thickness of Quaternary sediment and late Quaternary early Tertiary topography for the part of lower reaches of Narmada valley in a systematic way using the shallow seismic method, that records both horizontal and vertical components of the microtremor (ambient noise) caused by natural processes. The measurements of microtremors were carried out at 31 sites spaced at a grid interval of 5 km s using Lennartz seismometer (5 s period) and City shark-II data acquisition system. The signals recorded were analysed for horizontal to the vertical (H/V) spectral ratio using GEOPSY software. For the present study, we concentrate on frequency range between 0.2 Hz and 10 Hz. The thickness of unconsolidated sediments at various sites is calculated based on non-linear regression equations proposed by Ibs-von Seht and Wohlenberg (1999) and Parolai et al. (2002). The estimated thickness is used to plot digital elevation model and cross profiles correlating with geomorphology and geology of the study area. (C) 2011 Elsevier Ltd. All rights reserved.

High resolution facies record on late Holocene flood plain sediments from lower reaches of Narmada Valley, Western India

A high resolution quantitative granulometric record for site Uchediya 21A degrees 43'2.22aEuro(3) N, 73A degrees 6'26.22aEuro(3) E; 10 m a. s. l.] gives understanding towards accretion history of the late Holocene flood plain in the lower reaches of Narmada River. Two sediment facies (sandy and muddy) and seven subfacies (sandy subfacies: St(MS+FS+CS), SmFS+MS, Sl(FS+VFS), and St(MS + CS); muddy subfacies: FmSILT+VFS+FS, FmSILT+VFS (O) and FmSILT+VFS (T)) are identified based on cluster analysis supplemented with sedimentary structures observed in field and other laboratory data. Changes in hydrodynamics are further deduced based on various sedimentological parameters and their ratios leading to arrive at a depositional model.

Study of ground state phases for spin-1/2 Falicov-Kimball model on a triangular lattice

The spin dependent Falicov-Kimball model (FKM) is studied on a triangular lattice using numerical diagonalization technique and Monte-Carlo simulation algorithm. Magnetic properties have been explored for different values of parameters: on-site Coulomb correlation U, exchange interaction J and filling of electrons. We have found that the ground state configurations exhibit long range Neel order, ferromagnetism or a mixture of both as J is varied. The magnetic moments of itinerant (d) and localized U) electrons are also studied. For the one-fourth filling case we found no magnetic moment from d- and f-electrons for U less than a critical value. `.2014 Elsevier Ltd. All rights reserved.

Effect of Super-exchange Interaction on Ground state Magnetic Properties of Spin-dependent Falicov-Kimball Model on a Triangular Lattice

Ground state magnetic properties are studied by incorporating the super-exchange interaction (J(se)) in the spin-dependent Falicov-Kimball model (FKM) between localized (f-) electrons on a triangular lattice for half filled case. Numerical diagonalization and Monte-Carlo simulation are used to study the ground state magnetic properties. We have found that the magnetic moment of (d-) and (f-) electrons strongly depend on the value of Hund's exchange (J), super-exchange interaction (J(se)) and also depends on the number of (d-) electrons (N-d). The ground state changes from antiferromagnetic (AFM) to ferromagnetic (FM) state as we decrease (N-d). Also the density of d electrons at each site depends on the value of J and J(se).

The role of intra- and inter-site exchange correlations in the extended Falicov-Kimball model on a triangular lattice

Ground state magnetic properties of the spin-dependent Falicov-Kimball model (FKM) are studied by incorporating the intrasite exchange correlation J (between itinerant d- and localized f-electrons) and intersite (superexchange) correlation J (between localized f-electrons) on a triangular lattice for two different fillings. Numerical diagonalization and Monte-Carlo techniques are used to determine the ground state magnetic properties. Transitions from antiferromagnetic to ferromagnetic and again to re-entrant antiferromagnetic phase is observed in a wide range of parameter space. The magnetic moments of d- and f-electrons are observed to depend strongly on the value off, J and also on the total number of d-electrons (N-d). (C) 2015 Elsevier Ltd. All rights reserved.

Congresso, imprensa e opinião pública : o caso da CPMI dos Sanguessugas

Avalia como a opinião pública é influenciada pela cobertura dos jornais sobre as atividades do Congresso Nacional a partir de um caso específico: a Comissão Parlamentar Mista de Inquérito que investigou a chamada máfia dos sanguessugas. Apresenta um histórico da cobertura que a imprensa escrita vem dispensando ao Legislativo nos últimos cinquenta anos. Aborda a evolução dos veículos de divulgação da Câmara dos Deputados e do Senado Federal até os dias de hoje. Analisa o papel das CPIs como instrumentos de fiscalização do legislativo e como recurso para dar visibilidade à atividade parlamentar junto à mídia e a opinião pública.

A Comissão de Legislação Participativa da Câmara dos Deputados e a flexibilização da iniciativa popular

Analisa as atividades desenvolvidas pela Comissão de Legislação Participativa da Câmara dos Deputados, no período de 2001 a 2004. Avalia o papel da Comissão na ampliação e flexibilização do instrumento de iniciativa popular e na capacidade de transformar a participação política da sociedade civil em leis.

Diário da Constituinte [gravação de vídeo] : [programa n. 116A]

A Assembleia Nacional Constituinte (ANC) realiza debate sobre a política econômica atual, preocupada em fazer uma Constituição voltada para a realidade . O primeiro encontro ocorreu com Walter Barelli, Diretor do Departamento Intersindical de Estudos Estatísticos Sócio-Econômicos - DIEESE, que apresentou estudos realizados sobre o Plano Bresser. Plínio Arruda Sampaio (PT-SP) afirma que, devido a subserviência da política econômica ao capital estrangeiro, o desemprego aumentou. Bresser Pereira, Ministro da Fazenda, fez um balanço da situação econômica do país e debateu o assunto durante seis horas, apresentando dados a respeito do seu plano. Dalton Canabrava (PMDB-MG) acha que o Plano Bresser é bem fundamentado. Cristina Tavares (PMDB-PE) defende o parlamentarismo para evitar a permanência no poder de ministros com tais teses. Carlos Sant'Anna (PMDB-BA) opina que a situação econômica é dramática. Luiz Inácio Lula da Silva (PT-SP) diz que existe uma distância entre o Executivo e o Legislativo. Delfim Netto (PDS-SP) gostou da exposição e diz que devemos saudar a volta da racionalidade na política econômica. César Maia (PDT-RJ) acredita que as medidas irão alongar e aprofundar a recessão. Gastoni Righi (PTB-SP) defende o debate para encontrar as melhores soluções dentro da futura Carta. Bresser Pereira diz que o plano de congelamento está dando certo.

Diário da Constituinte [gravação de vídeo] : [programa n. 122A]

Termina o prazo para apresentação de emendas ao anteprojeto da Constituição. Foram apresentadas 5.607 emendas. Geraldo Campos (PMDB-DF) defende duas emendas sobre o direito de greve e benefício aos servidores públicos. Amaury Muller (PDT-RS) acredita que o conceito de empresa nacional precisa ser refeito. Carlos Sant'Anna (PMDB-BA) destaca o sistema de governo, ao qual pretende dar um caráter mais presidencialista, mas com regras parlamentaristas bem nítidas. Bernardo Cabral (PMDB-AM) diz que 80% das emendas apresentadas são de mérito e serão indeferidas, pois nesta fase o conteúdo do anteprojeto não pode ser alterado. Explicação sobre as próximas fases da tramitação do anteprojeto da Assembleia Nacional Constituinte (ANC). Grupos colhem assinaturas para emendas populares.

Diário da Constituinte [gravação de vídeo] : [programa n. 120A]

O anteprojeto de Constituição, com 501 artigos, apresentado por Bernardo Cabral, Relator da Comissão de Sistematização, não está agradando todos os constituintes. Orlando Pacheco (PFL-SC) diz que o texto é prolixo e pouco objetivo. Dalton Canabrava (PMDB-MG) imaginava um enxugamento e diz que o texto da Constituição está muito grande. Bernardo Cabral (PMDB-AM) defende-se afirmando que o texto é a compatibilização dos artigos aprovados nas comissões temáticas. Mário Covas (PMDB-SP) explica que a Comissão de Sistematização destacou as ideias e os conceitos das subcomissões e as reuniu em um único projeto. O Líder do Governo Carlos Sant'Anna (PMDB-BA) acredita que, se o texto for aprovado, o país ficará ingovernável. Adolfo Oliveira (PL-RJ) esclarece que as emendas de mérito só serão aceitas em relação ao anteprojeto da 8ª Comissão, por não ter finalizado os trabalhos. Quanto ao restante do texto, ele afirma que só serão admitidas emendas de compatibilização ou de adequação. Afonso Arinos (PFL-RJ), Presidente da Comissão de Sistematização, declara que sua decisão pessoal será sempre no sentido de observância das regras do Regimento da Assembleia Nacional Constituinte, mas por uma questão de inclinação natural para as decisões liberais, ele submeterá sua interpretação ao Plenário da Comissão. Marcelo Cordeiro (PMDB-BA), 1º Secretário da Assembleia Nancional Constituinte (ANC), conclui que a Casa conseguiu reunir os principais problemas brasileiros e que agora é necessário insistir no processo de uma grande negociação nacional para uma Constituinte que seja a expressão dos interesses e da vontade da nação. Octávio Elísio (PMDB-MG) quer a negociação, sem aceitar a interferência de ninguém que queira impor sobre a Constituinte determinados princípios e problemas. Sigmaringa Seixas (PMDB-DF) relata a existência de setores que querem apresentar um anteprojeto alternativo, elaborado possivelmente em "gabinetes palacianos", o que seria um absurdo, uma traição. Adolfo Oliveira (PL-RJ) relata que o anteprojeto é responsabilidade dos constituintes e que o presidente José Sarney pode confiar no patriotismo e na dedicação destes constituintes.