14 research outputs found
Defoliation symptoms on trees planted at a restoration site in Sabah, Malaysia
A study on defoliation of selected tree species was conducted at a forest restoration site located at Species Demo Plot in Luasong, Tawau Sabah. The study site is part of the INIKEA Forest Rehabilitation Project managed by Yayasan Sabah. The objective of this study was to determine the type and variation of defoliation symptoms observed on the foliage of eight to ten years old trees of Dipterocarpus conformis (KBK), Diospyros sp. (KMLM), Dryobalanops lanceolata (KPJ), Pentace laxiflora (TDH), Pentace adenophora (TDB) and Hopea ferruginea (SMKU) that were planted by line planting method. Sampling was conducted in July 2017 for a period of one week. Four replicates for each tree species was sampled. Defoliation symptoms were assessed on the crown of the trees. The mean defoliation symptom occurrence was calculated to represent each tree species. The mean defoliation symptoms among the six tree species were tested by using the Chi-square statistical analysis. Defoliation symptom occurrence across the six species of trees was categorized as herbivory, egg cases, leaf miners, leaf rollers, and galls. The highest percentage of defoliation symptom was herbivory (44.71%), followed by both egg cases and leaf miners (24.71% respectively), and only 1.18% of galls, which was the lowest. The highest mean defoliation symptom occurrence was recorded on D. lanceolata, with a mean of 4.75 occurrence, while the lowest mean defoliation symptom occurrence of 3.00 was recorded on both Diospyros sp. and H. ferruginea. Results of the Chi-square analysis indicated no significant difference (p>0.05) in the mean occurrence of defoliation symptoms across the six species of trees
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Exposure age, terrestrial age and pre-atmospheric radius of the Chinguetti mesosiderite: Not part of a much larger mass
We measured the concentrations of the cosmogenic radionuclides 14C (half-life = 5.73 × 103 years) in the bulk and of 10Be (1.5 × 106 years), 26Al (7.05 × 105 years), 36Cl (3.01 × 105 years) and the light noble gases in metal and stone fractions of the Chinguetti meteorite to investigate the controversial claim that the 4.5 kg mesosiderite is part of a much larger mass in the Mauritanian desert. Based on the 36Cl-36Ar, 10Be-21Ne and 26Al-21Ne pairs in the metal fraction, we derive an average cosmic-ray exposure age of 66 ± 7 million years (Ma). Chinguetti is now the third out of 20 mesosiderites with an exposure age between 60 and 70 Ma. This may be the first hint of a major impact on the parent body of the mesosiderites, which show ages ranging from 10–300 Ma (Terribilini et al., 2000). From the 14C-10Be pair we derive a terrestrial age of 18 ± 1 ka, which seems too recent to be consistent with the original description of the main mass having a heavily wind eroded base, overhung by the upper part of the meteorite. Finally, from the radionuclide concentrations in combination with Monte Carlo based calculations, we conclude that our sample of Chinguetti was irradiated at a depth of ~15 cm in an object not larger than 80 cm in radius. This is the most compelling evidence against the reports that the Chinguetti mesosiderite is a small fragment of a mass 100 m long and 40 m high
Incentive policies and china’s economic development: Change and challenge
Incentive policies have been emphasized by many governments as one of the major policy tools to promote economic development in their societies. For this paper I have examined the application of incentive policies in China to improve economic performance during China\u27s reform years. In the paper are theoretical reviews about various types of incentive policies and different arguments about their effects. The development of Chinese incentive policies is introduced and analysis of their achievements in improving economic growth and attracting foreign investment is presented. Challenging issues of incentive policies have been related to concerns about effectiveness and equity, accountability and transparency, as well as economic upgrade and balance. Implications of the Chinese development experience are provided for future study of incentive policies. © 2012 by PrAcademics Press
Using neuroimaging to understand the cortical mechanisms of auditory selective attention
Effets de la densité du peuplement sur les propriétés des écosystèmes des forêts subalpines dans le sud des Montagnes Rocheuses aux USA
Planning and Conducting a Pharmacogenetics Association Study
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/169261/1/cpt2270.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/169261/2/cpt2270_am.pd