Embryogenic suspensions of adult cork oak: the first step towards mass propagation.

Abstract Protocols have been established to clone adult cork oak trees by somatic embryogenesis using semisolid medium. However, for economically viable mass propagation, embryogenic cultures in liquid medium need to be developed. In this study, suspension cultures were initiated from embryo clusters obtained by secondary embryogenesis on a gelled medium lacking plant growth regulators. After 6 days of culture, these embryo clusters generated high cell density suspensions that also contained small organized structures (embryos and embryogenic clumps). As the culture duration increased, tissue necrosis and fewer embryogenic structures were observed and the establishment of suspension cultures failed. An alternative method was found adequate for initiation of embryogenic suspensions: embryo clusters from gelled medium were briefly shaken in liquid medium and detached cells and embryogenic masses of 41?800 lm were used as inoculum. Maintenance of embryogenic suspensions was achieved using a low-density inoculum (43 mg l-1) by subculturing four embryogenic clumps of 0.8?1.2 mm per 70 ml of medium. Proliferation ability was maintained for almost 1 year through ten consecutive subcultures. The initiation and maintenance protocols first developed for a single genotype were effective when tested on 11 cork oak genotypes.

Electrophoretic Deposition of Transparent ZnO Thin Films from Highly Stabilized Colloidal Suspensions

The parameters that control the stability of ZnO-nanoparticles suspensions and their deposition by electrophoretic deposition were studied, so as to organize the assembly and compaction of nanoparticles. The addition of cationic polyelectrolyte - Polyethylenimine (PEI) - with different molecular weights was investigated, in order to study their effectiveness and the influence of the molecular weight of the organic chain on suspensions dispersion. It was found that PEI with the highest molecular weight provided better dispersion conditions. Cathodic EPD was performed under previously optimized suspensions conditions and over electropolished stainless steel substrates. Experimental results showed that the EPD process in these conditions allows obtaining dense transparent ZnO thin films. Deposition times and intensities were optimized by analyzing the resulting thin films characteristics. Finally, the deposits were characterized by FE-SEM, AFM, and different spectroscopic techniques.

Photoacoustic effect measurement in aqueous suspensions of gold nanorods caused by low-frequency and low-power near-infrared pulsing laser irradiation

When aqueous suspensions of gold nanorods are irradiated with a pulsing laser (808 nm), pressure waves appear even at low frequencies (pulse repetition rate of 25 kHz). We found that the pressure wave amplitude depends on the dynamics of the phenomenon. For fixed concentration and average laser current intensity, the amplitude of the pressure waves shows a trend of increasing with the pulse slope and the pulse maximum amplitude.We postulate that the detected ultrasonic pressure waves are a sort of shock waves that would be generated at the beginning of each pulse, because the pressure wave amplitude would be the result of the positive interference of all the individual shock waves.

Assessment of the influence of the elastic properties of rail vehicle suspensions on safety, ride quality and track fatigue

A sensitivity analysis has been performed to assess the influence of the elastic properties of railway vehicle suspensions on the vehicle dynamic behaviour. To do this, 144 dynamic simulations were performed modifying, one at a time, the stiffness and damping coefficients, of the primary and secondary suspensions. Three values were assigned to each parameter, corresponding to the percentiles 10, 50 and 90 of a data set stored in a database of railway vehicles.After processing the results of these simulations, the analyzed parameters were sorted by increasing influence. It was also found which of these parameters could be estimated with a lesser degree of accuracy in future simulations without appreciably affecting the simulation results. In general terms, it was concluded that the highest influences were found for the longitudinal stiffness and the lateral stiffness of the primary suspension, and the lowest influences for the vertical stiffness and the vertical damping of the primary suspension, with the parameters of the secondary suspension showing intermediate influences between them.

Oxidative Burst and Hypoosmotic Stress in Tobacco Cell Suspensions

Oxidative burst constitutes an early response in plant defense reactions toward pathogens, but active oxygen production may also be induced by other stimuli. The oxidative response of suspension-cultured tobacco (Nicotiana tabacum cv Xanthi) cells to hypoosmotic and mechanical stresses was characterized. The oxidase involved in the hypoosmotic stress response showed similarities by its NADPH dependence and its inhibition by iodonium diphenyl with the neutrophil NADPH oxidase. Activation of the oxidative response by hypoosmotic stress needed protein phosphorylation and anion effluxes, as well as opening of Ca2+ channels. Inhibition of the oxidative response impaired Cl− efflux, K+ efflux, and extracellular alkalinization, suggesting that the oxidative burst may play a role in ionic flux regulation. Active oxygen species also induced the cross-linking of a cell wall protein, homologous to a soybean (Glycine max L.) extensin, that may act as part of cell volume and turgor regulation through modification of the physical properties of the cell wall.

Drivers license suspensions for failure to appear in court.

National Highway Traffic Safety Administration, Washington, D.C.

Report by the Governor of Iowa of pardons, suspensions and commutations and remission of fine.

Description based on: 1965-1967.

Life thoughts, gathered from the extemporaneous discourses of Henry Ward Beecher /

Preface signed: Edna Dean Proctor.

Destabilization-aggregation of dilute colloidal suspensions by polyelectrolytes.

Vita.

The form of process, before the Lords of Council and Session, observed in advocations, ordinary actions, suspensions : shewing also, the manner of making protestations for remedy in law, and how summons thereon was brought before the Parliament of Scotland : and the way how, since the union, such process is laid before the House of Peers : with the form of process before the Lords of Session, as commissioners appointed by Parliament, for plantation of kirks, valuation and sale of tythes : to all which is prefix'd the present state of the College of Justice, giving an account of the members thereof, and of the order observed by the Lords of Session in judging causes : with the fees and prices of writs paid to the several offices and members of the session : written for the use of students in Spotiswood's College of Law /

Mode of access: Internet.

The American orator's own book : a manual of extemporaneous eloquence including a course of discipline for the faculties of discrimination, arrangement and oral discussion and also practical exercises in reading, recitations and declamatory debate : intended for the use of colleges, schools, students of oratory, and all public speakers.

Mode of access: Internet.

Hints on extemporaneous preaching.

Mode of access: Internet.

Hints on extemporaneous preaching /

Mode of access: Internet.

Hints on extemporaneous preaching /

Mode of access: Internet.

Hints on extemporaneous preaching /

Includes bibliographical references.