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Chinese Journal Of Geochemistry 2012年第4期31卷 355-361页

作者： oden m.i. igonor E.E. Department of Geology University of CalabarP.M.B.1115 CalabarNigeria Petra Prospectors Limited Nigeria

minerals in general and rare-metals in particular are of invaluable importance in the development and industrialization of any *** is true as they could affect a nation's national income,employment ratio,Gross National Product,and its entire *** study area(western Oban massif-SE Nigeria) was investigated for its specialty metals bearing potentials because of(1) its geology,which is similar to other specialty metals bearing areas of the world;(2) past works,which points to the area as a likely source of economic deposit of such metals;and(3) the soaring cost of these rare metals in the light of recent upsurge in global information/telecommunication *** from the study,show that only cesium(Cs) and beryllium(Be) show minute signs or indications of enrichment if properly *** these metals should be studied in details to ascertain their economic *** rocks are too deficient in the other rare-metals(lithium,zirconium,strontium,tantalite,niobium,tungsten,gallium,and chromium) to warrant further analysis.

关键词：特种金属尼日利亚地球化学方法电位伟晶岩稀有金属矿地块国民生产总值

Gap characteristics and their effects on regeneration,dominance and early growth of woody species

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Journal of Plant Ecology 2009年第1期2卷 21-29页

作者： indra Prasad Sapkota Per Christer oden Swedish University of Agricultural Sciences Southern Swedish Forest Research CentreTropical Silviculture and Seed Science GroupPO Box 49SE-23053 AlnarpSweden

Aims We aim to examine the canopy gap characteristics and evaluate their influence on regeneration,dominance and the early growth of woody species in seasonally dry Shorea robusta forests(Sal forests).methods Sixty canopy gaps were surveyed in six randomly located transects belts in seasonally dry subtropical Sal forests of central *** transect belt was followed until 10 gap sites were *** equation for the area of an ellipse was used to calculate the size of canopy gap,measuring the longest axis and its perpendicular shorter ***,sizes,ages and causes of tree falls creating canopy gaps along with number and sizes of border trees were identified and *** gap inventories were carried out using square 25-m2 quadrats placed in the middle of each *** individuals>2 m.i. height within the quadrat were identified at the species level and their diameter at breast height was *** assigned a nested 4-m2 quadrat to the corner of each 25-m2 quadrat,within which all woody individuals>10 cm tall were identified at the species level,and counted them and their regeneration mechanisms were *** height and collar diameter of the tallest individuals were *** statistics was calculated for the variables of interests and Pearson correlation,linear regression,independent-sample t-test and chi-square test were used to relate them and to test for their *** Findings The study found mean gap size of 283 m2 and;50%gaps of 10–15 years *** created by natural single-tree falls were significantly more numerous,and their mean size was significantly smaller than those resulting from artificial causes or multiple-tree *** size correlated with the basal area of felled trees,but it did not correlate with the number of tree *** tree fall basal area was significantly positively correlated to the seed-originated seedling to resprout ratio,it was negatively correlated,along with gap area and th

关键词： canopy gap seedling density seedling growth basal area Sal forests Nepal

Pre-sowing treatment for breaking dormancy in Acer velutinum Boiss. seed lots

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Journal of Forestry Research 2013年第2期24卷 273-278页

作者： mostafa Farhadi mulualem Tigabu Alireza Ghasemi Arian mehdi Sharifani Abolfazl Daneshvar Per Christer oden Swedish University of Agricultural Sciences Southern Swedish Forest Research Centre Education Center of Jihad-Agriculture Gorgan University of Agricultural Sciences and Natural Resources Horticulture Department

Acer velutinum Boiss is a valuable tree species native to iran, and its seeds possess physiological dormancy that hampers seedling production in the nursery for large-scale reforestation efforts. The aim of this study was to determine the optimal dormancy breaking treatments for A. velutinum seeds. We conducted a factorial experiment involving six seed lots collected along an elevation gradient from 300 to 1800 m at 300 m.i.terval and four cold-m.i.t stratification periods （0, 4, 8 and 16 weeks） at 4℃ and 70% relative humidity. The result shows that the germination of cold-m.i.t stratified seeds was significantly （p 〈 0.0001） higher than the control for all seed lots. The highest germination capacity was recorded after 16 weeks of cold-m.i.t stratification for all seed lots （68% 88% depending on the seed lot） except those collected from mid altitude sites （600 and 900 m） that germinated equally well （≥ 75%） after 4and 8-week of clod-m.i.t stratification compared to the other seed lots. The mean germination time was significantly shorter （12 to 19 days, depending on the seed lot） for seeds stratified for 16 weeks than for untreated seeds. it can be concluded that：（1） cold-m.i.t stratification for 16 weeks is the best pre-sowing treatment for breaking dormancy in A. velutinum seeds; and （2） seeds should be collected from mid altitude sites （600 and 900 m） to get more than 80% germination within 15 days, and these seed lots even required shorter cold-m.i.t stratification period（eight weeks） than other seed lots.

关键词： cold-stratification altitude physiological dormancy velvet maple seed germination

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再灌注损伤在挤压综合征发病机理中的作用

国外医学（创伤与外科基本问题分册） 1992年第2期13卷 88-90页

作者： oden m 花天放

挤压综合症的死亡率和发病率较高,其病理生理过程尚不清楚,但再灌注诱导的损伤起有重要作用。再灌注损伤主要包括氧自由基释放、缺血肌内的钙大量积聚和白细胞浸润。鉴于不进行再灌注,缺血肌难以存活,其解救措施在于减少缺血再灌注损伤。

关键词：再灌注损伤挤压综合征

需要体外生命支持的新生儿甲状腺毒症并持续肺动脉高压

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世界核心医学期刊文摘（儿科学分册） 2006年第5期2卷 58-59页

作者： oden J. Cheifetz i.m. 刘莉 Division of Pediatric Endocrinology and Diabetes Box 3080 Duke Children's Hospital Durham NC 27710 United StatesDr

We report a case of neonatal Graves’disease involving an infant with severe persistent pulmonary hypertension (PPHN) associated with neonatal thyrotoxicosis that necessitated extracorporeal membrane oxygenation. Hyperthyroidism, although uncommon in the newborn period, has been associated with pulmonary hypertension among adults. The exact mechanisms responsible for this effect on pulmonary vascular pressure are not well understood. Recent studies have provided evidence that thyrotoxicosis has direct and indirect effects on pulmonary vascular maturation, metabolism of endogenous pulmonary vasodilators, oxygen economy, vascular smooth muscle reactivity, and surfactant production, all of which may contribute to the pathophysiologic development of PPHN. Therefore, because PPHN is a signifi cant clinical entity among term newborns and the symptoms of hyperthyroidism may be confused initially with those of other underlying disorders associated with PPHN (eg, sepsis), it would be prudent to perform screening for hyperthyroidism among affected newborns.

关键词：持续肺动脉高压甲状腺毒症新生儿体外生命支持甲状腺功能亢进持续性肺动脉高压肺血管压力 Graves病表面活性物质平滑肌反应性

impact of disturbance from roadworks on Pteleopsis suberosa regeneration in roadside environments in Burkina Faso, West Africa

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Journal of Forestry Research 2009年第4期20卷 355-361,I0007页

作者： Fidèle BOGNOUNOU Patrice SAVADOGO Adjima THiOm.i.NO mulualem TiGABU issaka Joseph BOUSSim Per Christer oden Sita GUiNKO Université de Ouagadougou Unité de Formation et Recherche en Sciences de la Vie et de la Terre Swedish Univ. of Agricultural Sciences Faculty of Forest Sciences Southern Swedish Forest Research Centre Centre National de la Recherche Scientifique et Technologique Institut de l’Environnement et de Recherches Agricoles Département Productions Forestières

The seedling population structure of Pteleopsis suberosa and their regeneration mechanisms were investigated in four roadside environments （graded, adjacent, intermediate and ungraded areas） along paved and unpaved roads in West Africa. A total of 203 quadrats of 2 m × 5 m.i. size were surveyed and placed along transects parallel to the roads. Within each quadrat, the total number of seedlings and the number of living shoots per seedling base were recorded. Regeneration mechanisms were determined by assessing basal and aerial sprouts and excavating the root systems below ground level. The results show that the total seedling density and the densities of single- and multi-stemmed individuals varied significantly （p 〈 0.05） among the four roadside environments. However, all seedlings were produced asexually; root suckers were predominant （98%） compared to water sprout （1%） and coppices （less than 1%）. This study demonstrates that an intermediate level of soil disturbance from grading along paved and unpaved roads may stimulate P. suberosa regeneration by root suck- ering. Road type （paved and unpaved） did not affect seedling density, but was a highly significant variable in relation to the coppicing ability of P. suberosa populations in roadside sites. in conclusion, P. suberosa is a disturbance-tolerant species which can proliferate m.i.ly by root suckering after roadwork disturbance.

关键词： Pteleopsis suberosa roadwork disturbance, seedling, regeneration, root sucker