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Acacia hybrid (A. mangium × A. auriculiformis) clones are planted on a large scale in Vietnam and it is desirable to expand the genetic base beyond the 10 commercial clones that comprise most of the plantation estate. Two approaches for developing elite clones from new Acacia hybrid genotypes derived from open-pollinated pure-species seedlots were compared. Method 1 involved identifying candidates in the nursery on the basis of seedling morphology followed by field trials of about 5000 putative hybrid seedlings. At 2 years, the best 3% of seedling candidates were reselected, captured and propagated for clonal screening trials. Method 2 captured and then clonally tested all putative hybrid genotypes identified on their morphology in pure-species field progeny trials at age 2 years. Method 1 was found to be much more effective at identifying promising new clones. Eighty-one of 196 candidate clones from this method had stem diameters at 2-3 years greater than or equal to the mean of commercial clone controls included in the clone trials. Method 2 yielded only 13 similarly promising new clones from 262 candidates. Maternal parents of both species yielded promising new clones. Overall timelines and a strategy are proposed and discussed for developing new elite Acacia hybrid clones, superior not only in growth but also in disease tolerance, wind-firmness and other important traits.Acacia hybrid (A. mangium × A. auriculiformis) clones are planted on a large scale in Vietnam and it is desirable to expand the genetic base beyond the 10 commercial clones that comprise most of the plantation estate. Two approaches for developing elite clones from new Acacia hybrid genotypes derived from open-pollinated pure-species seedlots were compared. Method 1 involved identifying candidates in the nursery on the basis of seedling morphology followed by field trials of about 5000 putative hybrid seedlings. At 2 years, the best 3% of seedling candidates were reselected, captured and propagated for clonal screening trials. Method 2 captured and then clonally tested all putative hybrid genotypes identified on their morphology in pure-species field progeny trials at age 2 years. Method 1 was found to be much more effective at identifying promising new clones. Eighty-one of 196 candidate clones from this method had stem diameters at 2-3 years greater than or equal to the mean of commercial clone controls included in the clone trials. Method 2 yielded only 13 similarly promising new clones from 262 candidates. Maternal parents of both species yielded promising new clones. Overall timelines and a strategy are proposed and discussed for developing new elite Acacia hybrid clones, superior not only in growth but also in disease tolerance, wind-firmness and other important traits.Acacia hybrid (A. mangium × A. auriculiformis) clones are planted on a large scale in Vietnam and it is desirable to expand the genetic base beyond the 10 commercial clones that comprise most of the plantation estate. Two approaches for developing elite clones from new Acacia hybrid genotypes derived from open-pollinated pure-species seedlots were compared. Method 1 involved identifying candidates in the nursery on the basis of seedling morphology followed by field trials of about 5000 putative hybrid seedlings. At 2 years, the best 3% of seedling candidates were reselected, captured and propagated for clonal screening trials. Method 2 captured and then clonally tested all putative hybrid genotypes identified on their morphology in pure-species field progeny trials at age 2 years. Method 1 was found to be much more effective at identifying promising new clones. Eighty-one of 196 candidate clones from this method had stem diameters at 2-3 years greater than or equal to the mean of commercial clone controls included in the clone trials. Method 2 yielded only 13 similarly promising new clones from 262 candidates. Maternal parents of both species yielded promising new clones. Overall timelines and a strategy are proposed and discussed for developing new elite Acacia hybrid clones, superior not only in growth but also in disease tolerance, wind-firmness and other important traits.Acacia hybrid (A. mangium × A. auriculiformis) clones are planted on a large scale in Vietnam and it is desirable to expand the genetic base beyond the 10 commercial clones that comprise most of the plantation estate. Two approaches for developing elite clones from new Acacia hybrid genotypes derived from open-pollinated pure-species seedlots were compared. Method 1 involved identifying candidates in the nursery on the basis of seedling morphology followed by field trials of about 5000 putative hybrid seedlings. At 2 years, the best 3% of seedling candidates were reselected, captured and propagated for clonal screening trials. Method 2 captured and then clonally tested all putative hybrid genotypes identified on their morphology in pure-species field progeny trials at age 2 years. Method 1 was found to be much more effective at identifying promising new clones. Eighty-one of 196 candidate clones from this method had stem diameters at 2-3 years greater than or equal to the mean of commercial clone controls included in the clone trials. Method 2 yielded only 13 similarly promising new clones from 262 candidates. Maternal parents of both species yielded promising new clones. Overall timelines and a strategy are proposed and discussed for developing new elite Acacia hybrid clones, superior not only in growth but also in disease tolerance, wind-firmness and other important traits. [ABSTRACT FROM AUTHOR]

We secured spectral images of the circumnuclear, 12 × 10 arcsec2 region of the Seyfert 2 galaxy NGC 5728 with the Optically Adaptive System for Imaging Spectroscopy at the Canada–France–Hawaii Telescope 3.6-m telescope. The radial velocity distribution of the two bright zones, main central (C) core and north-west (NW) core, and strategically important points along the position angles, PA 33°, 90°, 123° and 143°, are analysed. The large-scale reconstructed monochromatic images of the Hα, Hβ, [O iii] and [N ii] lines show a bipolar morphology along PA ∼ 123°. The prominent elliptical ring is seen in the Hα and Hβ monochromatic images. Our analysis implies that this ring is rotating in the same clockwise direction as that of the galactic disc; this elliptical ring is in fact a projected result of a circular ring of radius ∼5.4 arcsec, with (nearly aligned with the host galactic plane). We used the [O iii]5007 line profiles for a detailed analysis of kinematics in the circumnuclear region of the NGC 5728. The [O iii]5007 line profiles reveal distinct kinematical structures. (1) The strongest component of Doppler peaks: two core components, consisting of the receding main C-core and the approaching NW-core with the radial velocities, and −240 (or −250) km s−1, respectively. These two cores consist of a roughly spherically symmetric distribution of the gas with radii of (at ) and 0.9 arcsec (at ), respectively. Hints of the presence of inflows around these cores are observed. (2) The next strong line profile component: this component corresponds to the bipolar cone aligned . (3) The reverse S-shaped kinematical boundary which runs through the double-peaked zone of 6–7 arcsec long in the galactic major axis direction is likely to be caused by a combination of the disc rotation of the host galaxy and the revolution of the two central cores. [ABSTRACT FROM AUTHOR]

The performances of electroflotation (EF) on the thickening of activated sludge were investigated using laboratory scale batch flotation reactors. Four activated sludges including bulking sludges were tested. After 30minutes of EF operation, 57-84% of sludge volume reduction could be achieved by EF, while only about 1.5-14% could be obtained by gravity thickening for the same period. After thickening the effluent water quality in terms of TCOD, SS, and turbidity was improved by EF operation for all sludge samples. In addition, the EF thickened sludge showed much better dewaterability both in SRF and cake solid content. It is induced that the air bubbles entrapped in the thickened sludge play a key role in the observed dewaterbility improvement. [ABSTRACT FROM AUTHOR]

Investigates the biological removal of nitrogen from industrial wastewater by a novel oxic and anoxic type process with natural zeolite circulation. Two types of raw wastewater with high strength ammonia nitrogen; Effectiveness of the proposed biological reactors with zeolite powder circulation.