Floral Phenology of a Stand of Mountain Ash (Eucalyptus regnans F. Muell.) In Gippsland, Victoria

1980 ◽  
Vol 28 (4) ◽  
pp. 393 ◽  
Author(s):  
AR Griffin
Keyword(s):  
Gene Flow ◽  
Important Determinant ◽  
Flowering Phenology ◽  
Structural Level ◽  
Relative Time ◽  
Eucalyptus Regnans ◽  
Floral Phenology ◽  
Mountain Ash ◽  
The Mean ◽  
Individual Trees

Flowering phenology was observed in a stand of Eucalyptus regnans F.Muell. at Narracan, Gippsland, Vic. during 1977 and again in 1979. The first tree flowered on 15 February in 1977 and on 30 January in 1979. Flowering of all trees was completed after 90 and 100 days respectively, and in both seasons the modal value for the number of trees concurrently in flower occurred 40 days after commencement. There was a highly significant association, between years, for the relative time and duration of flowering of individual trees. Tree size was not an important determinant of flowering attributes. Trees were not randomly distributed with respect to peak flowering time: thus flowering of adjacent trees tended to be synchronous. Detailed observation of flowering within the crowns of three trees showed that within inflorescences the mean period between anthesis of the earliest and latest flowers was 6 days, and within branches 14 days. The degree to which flowering was synchronous within the crown varied consistently between trees at each structural level assessed, which suggested genetic control of this trait. Implications of the floral phenology for the breeding system and gene flow of the species are discussed.

scholarly journals Genetic analysis of silver-fir populations in the North Carpathian and Sudeten Mountains

2011 ◽  
Vol 73 (4) ◽  
pp. 285-292 ◽  
Author(s):  
Leon Mejnartowicz
Keyword(s):  
Gene Flow ◽  
Abies Alba ◽  
Genetic Distances ◽  
Silver Fir ◽  
Starch Gel Electrophoresis ◽  
Effective Number ◽  
The North ◽  
Rare Alleles ◽  
The Mean ◽  
Individual Trees

Seeds collected from individual trees in the 16 Carpathian and 2 Sudeten silver-fir (<em>Abies alba</em>) populations were studied with the starch gel electrophoresis in megagametophytes using 14 enzyme systems with 28 loci. The results show that the geographical distance between populations are in a small part reflected in genetic distances. There are two main groups of populations: Sudeten and Carpathian with a very big genetic distance between them. Other populations consist of a few small groups with low gene flow between them (<em>N<sub>m</sub></em> = 3.286). About 80% of genetic variation is located within populations (<em>F<sub>ST</sub></em> = 0.223). Average values for genetic multiplicity and diversity for Carpathian populations are as follows: number of alleles per locus: <em>Na</em> = 2.308, with effective number of alleles <em>Ne</em> = 1.552 and proportion of polymorphic loci 71.21%. The mean number of alleles per locus (<em>Na</em>) varied from 2.107 to 2.607 in population. The mean effective number of alleles per locus (<em>Ne</em>) ranged from 1.429 to 1.662. Average Fis for Carpathian populations was -0.021, which means that there is small excess of heterozygotes. The average observed heterozygosity amounted to <em>Ho</em> = 0.275 and expected heterozygosity was <em>He</em> = 0.269. The dendrogram structure and presence of rare alleles found in silver-fir of Czech, and Slovakian populations allow for a hypothesis that in postglaciation the silver-fir moved into the Polish Carpathians not westward from the east but from the south along river valleys from some Balkan refuges, getting North bypassing the High Tatra Range. This way, a highly diversified set of populations originated, differ in the presence of rare alleles. This differentiation is not prevented by a relatively small flow of genes between populations. The calculated gene flow <em>Nm</em> = 3.286 also indicates isolation between the populations. It means 3.3 immigrants per generation into the studied populations.

Retirement intentions of older consultant psychiatrists

2004 ◽  
Vol 28 (4) ◽  
pp. 130-132 ◽  
Author(s):  
Alex Mears ◽  
Tim Kendall ◽  
Cornelius Katona ◽  
Carole Pashley ◽  
Sarah Pajak
Keyword(s):  
Early Retirement ◽  
Response Rate ◽  
Important Determinant ◽  
Clinical Implications ◽  
Consultant Psychiatrist ◽  
Health Officer ◽  
Decisions To Leave ◽  
The Mean ◽  
The Uk ◽  
Retirement Intentions

Aims and MethodThis survey gathered data on the retirement intentions of consultant psychiatrists over the age of 50 years, in order to address retention issues. A questionnaire was sent to all 1438 consultants over this age in the UK.ResultsA total of 848 questionnaires were returned, an adjusted response rate of 59%. The mean age at which consultants intended to retire in this sample was 60 years (s.d. 4.16), suggesting a potential loss of 5725 consultant years. Reasons for early retirement are complex: factors encouraging retirement include too much bureaucracy, lack of free time and heavy case-loads; those discouraging retirement include enjoyment of work, having a good team and money. Mental Health Officer status is an important determinant in the decision to retire early.Clinical ImplicationsWith numerous vacancies in consultant psychiatrist posts throughout the UK, premature retirement is a cause for concern, possibly contributing to an overall reduction in consultant numbers of 5%. Addressing factors that influence consultants' decisions to leave the health service early should form an important part of an overall strategy to increase consultant numbers.

scholarly journals Assessment of genetic diversity among surian Toona sinensis Roem in progenies test using random amplified polymorphic DNA markers

2018 ◽  
Vol 22 (1) ◽  
pp. 22
Author(s):  
Jayusman Jayusman ◽  
Muhammad Na’iem ◽  
Sapto Indrioko ◽  
Eko Bhakti Hardiyanto ◽  
ILG Nurcahyaningsih
Keyword(s):  
Genetic Diversity ◽  
Dna Markers ◽  
Rapd Markers ◽  
Random Amplified Polymorphic Dna ◽  
Management Strategies ◽  
Genetic Distances ◽  
Sampled Data ◽  
Toona Sinensis ◽  
The Mean ◽  
Individual Trees

Surian Toona sinensis Roem is one of the most widely planted species in Indonesia. This study aimed to estimate the genetic diversity between a number of surian populations in a progeny test using RAPD markers, with the goal of proposing management strategies for a surian breeding program. Ninety-six individual trees from 8 populations of surian were chosen as samples for analysis. Eleven polymorphic primers (OP-B3, OP-B4, OP-B10, OP-H3, OP-Y6, OP-Y7, OP-Y8, OP-Y10, OP-Y11, OP-Y14, and OP-06) producing reproducible bands were analyzed for the 96 trees, with six trees per family sampled. Data were analyzed using GenAlEx 6.3, NTSYS 2.02. The observed percentage of polymorphic loci ranged from 18.2% to 50%. The mean level of genetic diversity among the surian populations was considered to be moderate (He 0.304). Cluster analysis grouped the genotypes into two main clusters, at similarity levels of 0.68 and 0.46. The first two axes of the PCoA explained 46.16% and 25.54% of the total variation, respectively. The grouping of samples into clusters and subclusters did not correspond with family and their distances, but the grouping was in line with the genetic distances of the samples.

scholarly journals Financial Integration in the GCC Region: Market Size Versus National Effects

2019 ◽  
Vol 31 (2) ◽  
pp. 309-316
Author(s):  
Kerim Peren Arin ◽  
Guglielmo Maria Caporale ◽  
Kyriacos Kyriacou ◽  
Nicola Spagnolo
Keyword(s):  
Financial Integration ◽  
Important Determinant ◽  
Equity Markets ◽  
Spillover Effects ◽  
Abu Dhabi ◽  
Stock Exchanges ◽  
Market Size ◽  
Market Capitalization ◽  
The Mean ◽  
Oil Crisis

AbstractThis paper examines financial spillovers between the four largest equity markets (by market capitalization) in the GCC region using a VAR-GARCH (1,1) framework that sheds light on interdependence as well as the effects of the 2014 oil crisis. Since the UAE is a federation including two stock exchanges (Abu Dhabi and Dubai), it is possible to test whether being part of a federal union matters more than market size in terms of financial integration. Our results suggest that the latter is more important, since we could not find evidence of stronger linkages between the Abu Dhabi and Dubai markets compared to those between other markets in the region. By contrast, there are significant spillover effects, both in the mean and in the volatility, from the largest market of Saudi Arabia to Qatar and the two markets in the UAE, which confirms that market capitalization is a more important determinant of financial integration than belonging to a federal union. Further, spillovers from the larger markets have become stronger as a result of the 2014 oil crisis. Finally, there is also evidence of spillovers from the smaller to the larger markets.

Geographic determinants of copper and molybdenum concentrations in serum at the end of the grazing season and associations with reproductive performance in beef cows from western Canada

2011 ◽  
Vol 91 (3) ◽  
pp. 423-431 ◽  
Author(s):  
Leanne Van De Weyer ◽  
Cheryl Waldner
Keyword(s):  
Reproductive Performance ◽  
Important Determinant ◽  
Beef Cows ◽  
Western Canada ◽  
Serum Concentrations ◽  
Soil Color ◽  
Grazing Season ◽  
Cu Deficiency ◽  
The Mean ◽  
Feed Samples

Van De Weyer, L. M. and Waldner, C. L. 2011. Geographic determinants of copper and molybdenum concentrations in serum at the end of the grazing season and associations with reproductive performance in beef cows from western Canada. Can. J. Anim. Sci. 91: 423–431. Serum concentrations of Cu and Mo were measured at the end of the summer grazing season in an observational field study of 783 breeding females from 66 cow-calf herds located in western Canada. The mean Cu concentration was 0.82 ppm (S, 0.30 ppm) and the mean Mo concentration was 0.056 ppm (S, 0.055 ppm). Serum Cu concentration differed across ecoregions (P=0.013). Serum Mo concentrations varied by ecoregion (P =0.002), soil type (P =0.011), soil color (P=0.018), and total precipitation during the growing season (P =0.004). Copper and Mo serum concentrations at the end of the grazing season were not associated with reproductive outcomes. Herd location is an important determinant of the risk of primary and secondary Cu deficiency and can inform the need for trace mineral testing of feed samples as well as supplementation.

Does nitrogen limit the growth of native eucalypt forests:some observations for mountain ash (Eucalyptus regnans)

2001 ◽  
Vol 52 (1) ◽  
pp. 111 ◽  
Author(s):  
P. M. Attiwill ◽  
P. M. Attiwill ◽  
B. M. May ◽  
B. M. May
Keyword(s):  
N Availability ◽  
Ecological Research ◽  
Biological Fixation ◽  
Ecological Processes ◽  
Eucalyptus Regnans ◽  
Rate Of Growth ◽  
Wild Fire ◽  
N Supply ◽  
Eastern Australia ◽  
Mountain Ash

It is often stated that the availability of N limits the rate of growth of native forests. We discuss this hypothesis with particular reference to the mountain ash (Eucalyptus regnans) forests of south-eastern Australia. The abundance of 15 N in leaves and soil of mountain ash forest is in accord with data for Northern Hemisphere temperate forests and for tropical forests,and indicates that N availability is relatively high.None of the nutrient elements has limited the rate of growth of mountain ash forest regenerating after major disturbance (clear-felling and intense wild-fire). There is some evidence that P may be limiting to some ecological processes (e.g. the rate of litter decomposition). We conclude that phosphorus is more likely to be limiting than nitrogen in mountain ash forest because nitrogen cycling is conservative and continual inputs of N through biological fixation supplement this conservative N supply, and the stands never become N-deficient. The development of methodologies to determine the rate of N2-fixation in forests should be of high priority in ecological research.

Economics of a nest-box program for the conservation of an endangered species: a reappraisal

2001 ◽  
Vol 31 (11) ◽  
pp. 1992-2003 ◽  
Author(s):  
Daniel A Spring ◽  
Michael Bevers ◽  
John OS Kennedy ◽  
Dan Harley
Keyword(s):  
Net Present Value ◽  
Population Recovery ◽  
Optimal Management ◽  
Present Value ◽  
Eucalyptus Regnans ◽  
Nest Boxes ◽  
Mountain Ash ◽  
Local Abundance ◽  
Leadbeater's Possum

An optimization model is developed to identify timing and placement strategies for the installation of nest boxes and the harvesting of timber to meet joint timber–wildlife objectives. Optimal management regimes are determined on the basis of their impacts on the local abundance of a threatened species and net present value (NPV) and are identified for a range of NPV levels to identify production possibility frontiers for abundance and NPV. We apply the model to a case study focusing on an area of commercially productive mountain ash (Eucalyptus regnans F. Muell.) forest in the Central Highlands region of Victoria, Australia. The species to be conserved is Leadbeater's possum (Gymnobelideus leadbeateri McCoy), which is locally limited by a scarcity of nesting hollows. The modeling is exploratory but indicates that nest boxes may offer a promising population recovery tool if consideration is taken of their placement and areal extent through time.

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