2,645 research outputs found
Plant species first recognised as naturalised for New South Wales in 2002 and 2003, with additional comments on species recognised as naturalised in 2000–2001
Information is provided on the taxonomy and distribution of 71 taxa of naturalised or naturalising plants newly recorded for the state of New South Wales during the period 1 January 2002 to 31 December 2003. Of these taxa, 32 are new records for Australia (prefaced with a †). These species are: Abutilon pictum, Acanthus mollis, †Aesculus indica (naturalising), Agapanthus praecox subsp. orientalis, Ajuga reptans, †Anigozanthos flavidus, Aquilegia vulgaris, Arbutus unedo, †Athertonia diversifolia (naturalising), †Bergenia x schmidtii (naturalising), Bromus catharticus subsp. stamineus, Bryophyllum daigremontianum, Bryophyllum fedtschenkoi, Calyptocarpus vialis, †Ceiba speciosa (naturalising), Cereus uruguayanus, †Cestrum x cultum, †Chamaecyparis lawsoniana, Cistus salviifolius, †Clematis montana, †Coprosma x cunninghamii, Coprosma robusta, Cornus capitata, Cotoneaster simonsii, Cotoneaster x watereri group, Crinum moorei, Cupressus lusitanica, †Cylindropuntia fulgida var. mamillata forma monstrosa, †Cylindropuntia prolifera, Cylindropuntia tunicata, Desmanthus virgatus, Drosanthemum candens, †Elaeagnus umbellata (naturalising), †Eragrostis trichophora, †Eupatorium lindleyanum, †Gibasis pellucida, Glechoma hederacea, †Hesperis matronalis, Hieracium aurantiacum subsp. carpathicola, †Inga edulis (naturalising), †Juniperus conferta (naturalising), †Justicia caudata, Lamium galeobdolon, Lathyrus tingitanus, †Lysimachia fortunei, †Maackia amurensis, †Monstera deliciosa, †Murdannia keisak, Odontonema tubaeforme, Oxalis vallicola, Phoenix canariensis, †Physostegia virginiana, Pinus patula, Pittosporum eugenioides, †Pittosporum ralphii, Pittosporum tenuifolium, Plectranthus ecklonii, †Potentilla vesca, †Prunus campanulata, †Rhododendron ponticum, Rosa luciae, Rubus rugosus, Ruellia squarrosa, †Senna multijuga, Stapelia gigantea, Stephanophysum longifolium, Strobilanthes anisophylla, †Tabebuia chrysotricha, †Tabebuia impetiginosa, †Tradescantia pallida and Ulmus x hollandica. Additional notes and name changes are recorded for plants first recognised as naturalised for New South Wales over the period 2000–2001. The identification of several naturalised taxa occurring in New South Wales has been corrected. Plants formerly identified as Pinus nigra var. corsicana are now considered to be Pinus halepensis; Cylindropuntia arbuscula is Cylindropuntia kleiniae, Cylindropuntia tunicata is Cylindropuntia rosea, Abrus precatorius subp. precatorius is now Abrus precatorius subsp. africanus and Cotoneaster ?horizontalis is Cotoneaster microphyllus. Further field studies have revealed that Cylindropuntia leptocaulis, Cylindropuntia spinosior, Hypericum kouytchense and Chamaesyce ophthalmica are more widespread than previously thought
A study to explore the use of orbital remote sensing to determine native arid plant distribution
The author has identified the following significant results. It is possible to determine, from ERTS imagery, native arid plant distribution. Using techniques of multispectral masking and extensive fieldwork, three native vegetation communities were defined and mapped in the Avra Valley study area. A map was made of the Yuma area with the aid of ground truth correlations between areas of desert pavement visible on ERTS images and unique vegetation types. With the exception of the Yuma soil-vegetation correlation phenomena, only very gross differentiations of desert vegetation communities can be made from ERTS data. Vegetation communities with obvious vegetation density differences such as saguaro-paloverde, creosote bush, and riparian vegetation can be separated on the Avra Valley imagery while more similar communities such as creosote bush and saltbush could not be differentiated. It is suggested that large differences in vegetation density are needed before the signatures of two different vegetation types can be differentiated on ERTS imagery. This is due to the relatively insignificant contribution of vegetation to the total radiometric signature of a given desert scene. Where more detailed information concerning the vegetation of arid regions is required, large scale imagery is appropriate
Direct measurement of high-lying vibrational repumping transitions for molecular laser cooling
Molecular laser cooling and trapping requires addressing all spontaneous
decays to excited vibrational states that occur at the level, which is accomplished by driving repumping transitions out of
these states. However, the transitions must first be identified
spectroscopically at high-resolution. A typical approach is to prepare
molecules in excited vibrational states via optical cycling and pumping, which
requires multiple high-power lasers. Here, we demonstrate a general method to
perform this spectroscopy without the need for optical cycling. We produce
molecules in excited vibrational states by using optically-driven chemical
reactions in a cryogenic buffer gas cell, and implement frequency-modulated
absorption to perform direct, sensitive, high-resolution spectroscopy. We
demonstrate this technique by measuring the spectrum of the
band in YbOH.
We identify the specific vibrational repump transitions needed for photon
cycling, and combine our data with previous measurements of the
band to determine all
of the relevant spectral constants of the state.
This technique achieves high signal-to-noise, can be further improved to
measure increasingly high-lying vibrational states, and is applicable to other
molecular species favorable for laser cooling.Comment: 14 pages, 5 figure
Mirror-Descent Methods in Mixed-Integer Convex Optimization
In this paper, we address the problem of minimizing a convex function f over
a convex set, with the extra constraint that some variables must be integer.
This problem, even when f is a piecewise linear function, is NP-hard. We study
an algorithmic approach to this problem, postponing its hardness to the
realization of an oracle. If this oracle can be realized in polynomial time,
then the problem can be solved in polynomial time as well. For problems with
two integer variables, we show that the oracle can be implemented efficiently,
that is, in O(ln(B)) approximate minimizations of f over the continuous
variables, where B is a known bound on the absolute value of the integer
variables.Our algorithm can be adapted to find the second best point of a
purely integer convex optimization problem in two dimensions, and more
generally its k-th best point. This observation allows us to formulate a
finite-time algorithm for mixed-integer convex optimization
Variation for N uptake system in maize: genotypic response to N supply
An understanding of the adaptations made by plants in their nitrogen (N) uptake systems in response to reduced N supply is important to the development of cereals with enhanced N uptake efficiency (NUpE). Twenty seven diverse genotypes of maize (Zea mays, L.) were grown in hydroponics for 3 weeks with limiting or adequate N supply. Genotypic response to N was assessed on the basis of biomass characteristics and the activities of the nitrate ([Formula: see text]) and ammonium ([Formula: see text]) high-affinity transport systems. Genotypes differed greatly for the ability to maintain biomass with reduced N. Although, the N response in underlying biomass and N transport related characteristics was less than that for biomass, there were clear relationships, most importantly, lines that maintained biomass at reduced N maintained net N uptake with no change in size of the root relative to the shoot. The root uptake capacity for both [Formula: see text] and [Formula: see text] increased with reduced N. Transcript levels of putative [Formula: see text] and [Formula: see text] transporter genes in the root tissue of a subset of the genotypes revealed that predominately ZmNRT2 transcript levels responded to N treatments. The correlation between the ratio of transcripts of ZmNRT2.2 between the two N levels and a genotype's ability to maintain biomass with reduced N suggests a role for these transporters in enhancing NUpE. The observed variation in the ability to capture N at low N provides scope for both improving NUpE in maize and also to better understand the N uptake system in cereals.Trevor Garnett, Darren Plett, Vanessa Conn, Simon Conn, Huwaida Rabie, J. Antoni Rafalski, Kanwarpal Dhugga, Mark A. Tester and Brent N. Kaise
Plant species first recognised as naturalised or naturalising for New South Wales in 2004 and 2005
Information is provided on the taxonomy and distribution of 62 taxa of naturalised or naturalising plantsm newly recorded for the state of New South Wales during the period 1 January 2004 and 31 December 2005 and 1 species treated in the 2002 revised Flora of New South Wales Volume 2 but overlooked in an earlier paper of this series. Of these taxa, 17 are new records for Australia (prefaced with a †). The 62 taxa are: Acer palmatum, †Acer saccharinum, Achillea filipendulina, Acokanthera oblongifolia, †Anemone hupehensis var. japonica, Berberis aquifolium, †Bidens aurea, †Brugmansia suaveolens, Brugmansia x candida, Buddleja dysophylla, †Convolvulus farinosus, Cordyline australis, Coriandrum sativum, Corymbia citriodora (Australian species naturalised outside its native range), Crassula ericoides subsp. ericoides, Crotalaria retusa (Australian species naturalised outside its native range), Cyperus prolifer, Echinochloa polystachya, Ficus carica, †Gladiolus dalenii, †Gladiolus cultivar, Hakea laurina (Western Australian species), Hemerocallis fulva var. fulva, Hieracium pilosella, Hydrangea macrophylla, Hydrocleys nymphoides, Hymenachne amplexicaulis, Hypericum calycinum, Impatiens balfouri, Indigofera spicata, Iris laevigata, †Juglans ailantifolia, Lilium lancifolium, Lygodium japonicum, Malephora crocea, Mauranthemum paludosum, Melastoma malabathricum, †Nassella tenuissima, Pelargonium quercifolium, †Phoenix reclinata, Phormium tenax, Pinus contorta, Podranea ricasoliana, †Polygonatum x hybridum, Polypremum procumbens, †Primula malacoides, Rhaphiolepis umbellata, Romneya coulteri, Romneya trichocalyx, Setaria incrassata, †Sideritis lanata, †Sorbus aucuparia, Spartium junceum, Stylosanthes guianensis, Stylosanthes humilis, †Symphoricarpos albus var. laevigatus, Syzygium paniculatum (Australian species naturalising outside its native range), Tibouchina urvilleana, †Tradescantia cerinthoides, †Utricularia sandersonii, Washingtonia filifera and Zephyranthes carinata. The overlooked species is Eugenia uniflora
- …