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Influence of mulching and tree shelters on 4-year survival and growth of zeen oak (Quercus canariensis) seedlings

Journal of forestry Research 2019年第1期30卷 129-141页

作者： Taher Mechergui Marta Pardos douglass f.jacobs facultédes Sciences de Bizerte Laboratoire des Ressources Sylvo-Pastorales (Institut Sylvo-Pastoral de Tabarka) Instituto Nacional de Investigacion y Tecnologia Agraria y Alimentaria (INIA) Centro de Investigacion Forestal Department of forestry and Natural Resources Hardwood Tree Improvement and Regeneration Center Purdue University

We assessed the effect of mulching and tree shelters on the establishment and early growth of zeen oak(Quercus canariensis Willd.) during the first 4 years after planting in Northwestern Tunisia. five mulch types(Italian Stone Pine(Pinus pinea L.), Lentisk(Pistacia lentiscus L.),and a combination of Italian Stone Pine and Lentisk(organic mulches), gravel(inorganic mulch) and control), and three tree shelter types(non-vented and vented tree shelters, and control) were tested. An increase in the number of internodes occurred under the gravel mulch, while a reduction in survival was found for the lentisk mulch. Tree shelters had no effect on survival, but increased mean height growth and reduced mean diameter growth during the 4 years(excepting a non-significant effect for vented tree shelter at year four). Comparison of the annual shoots and growth units(GU) between sheltered and unsheltered plants according to year of formation revealed two growth phases. In first phase, shoots were totally or partially inside the shelters; mean length of annual shoots and GU were greater for sheltered plants. The second phase was characterized by shoots emerging from shelters; mean length of annual shoots and GU were similar for all plants, with or without tree shelters. Results suggest that the use of tree shelters, particularly vented shelters, could contribute to the improvement of the artificial regeneration of zeen *** use of mulching alone or in combination with tree shelters did not improve zeen oak performance in the field.

关键词： Zeen oak Mulching Tree shelters Plantation Survival rate Growth

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Changes in soil properties under Eucalyptus relative to Pinus massoniana and natural broadleaved forests in South China

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Journal of forestry Research 2018年第5期29卷 1299-1306页

作者： Shuangshuang Chu douglass f.jacobs Joshua L.Sloan Li Xue Daoming Wu Shucai Zeng College of forestry and Landscape Architecture South China Agricultural University Department of forestry and Natural Resources Purdue University

The ecological effects of eucalypt plantations（EPs） have garnered increasing *** understand their effect on soil quality at a landscape scale,and to determine whether soil quality parameters differ due to different stand types,we evaluated soil characteristics in twenty-one groups of EPs,Pinus massoniana ***（PMPs） and natural broadleaved forests（NBfs）across Guangdong Province,*** the physical characteristics of soil hydrology and the properties of soil nutrients in A and B horizons were *** showed that,compared to NBfs,EPs and PMPs produced a shallower litter layer,reduced canopy density,higher soil bulk density,significantly lower total porosity,non-capillary porosity,total water volume,and hygroscopic water in the A horizon（P〈0.05）.Moreover,total N,available K,and soil organic carbon（SOC） in EPs and PMPs were significantly lower than in *** and PMPs did not differ significantly in N,P or K content,but PMPs had significantly lower SOC and boron in the A horizon than *** p H and poor capacity to buffer acidification generally occurred in all cover *** EPs and PMPs showed a decline in soil properties relative to NBfs,but EPs and PMPs exhibited no significant *** results indicate that actions are needed to ameliorate the potential negative effects on soil quality in forestry plantations.

关键词： Eucalyptus Pinus massoniana Plantations Soil organic matter Soil acidification Moisture retention capacity

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Three-dimensional analysis of age and sex differences in femoral head asphericity in asymptomatic hips in the United States

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World Journal of Orthopedics 2024年第8期15卷 754-763页

作者： Mahad M Hassan Aliya G feroe Brenton W douglass Andrew E Jimenez Benjamin Kuhns Charles f Mitchell Robert L Parisien Daniel A Maranho Eduardo N Novais Young-Jo Kim Ata M Kiapour Department of Orthopedic Surgery University of MinnesotaMinneapolisMN 55454United States Department of Orthopedic Surgery TRIA Orthopaedic CenterBloomingtonMN 55122United States Department of Orthopedic Surgery Boston Children’s HospitalBostonMA 02115United States Department of Orthopedic Surgery Mayo ClinicRochesterMN 55901United States Department of Orthopaedics and Rehabilitation Yale School of MedicineNew HavenCT 06510United States Department of Orthopedic Surgery American Hip Institute Research FoundationDes PlainesIL 60018United States Department of Orthopedic Surgery Mount SinaiNew YorkNY 10029United States Department of Biomechanics Medicineand Rehabilitation of the Locomotor SystemRibeirao Preto Medical SchoolUniversity of São PauloRibeirao Preto 14048-900São PauloBrazil

BACKGROUND The sphericity of the femoral head is a metric used to evaluate hip pathologies and is associated with the development of osteoarthritis and femoral-acetabular *** To analyze the three-dimensional asphericity of the femoral head of asymptomatic pediatric *** hypothesized that femoral head asphericity will vary significantly between male and female pediatric hips and increase with age in both *** Computed tomography scans were obtained on 158 children and adolescents from a single institution in the United States(8-18 years;50%male)without hip *** femoral measurements including the femoral head diameter,femoral head volume,residual volume,asphericity index,and local diameter difference were used to evaluate femoral head *** In both sexes,the residual volume increased by age(Pficantly smaller femoral head size in older ages(>13 years)in females,there were no sex-differences in residual volume and aspherity *** were no age-related changes in mean diameter difference in both sexes(P=0.07)with no significant sex-differences across different age groups(P=0.06).In contrast,there were significant increases in local aspherity(maximum diameter difference)across whole surface of the femoral head and all quadrants except the inferior regions in males(P=0.03).There were no sex-differences in maximum diameter difference at any regions and age group(P>0.05).Increased alpha angle was only correlated to increased mean diameter difference across overall surface of the femoral head(P=0.024).CONCLUSION There is a substantial localized asphericity in asymptomatic hips which increases with age *** 2D measured alpha angle can capture overall asphericity of the femoral head,it may not be sensitive enough to represent regional asphericity patterns.

关键词： Hip femoral head Sphericity Skeletal growth Sex differences

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Influence of lanthanum level and interactions with nitrogen source on early development of Juglans nigra

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Journal of Rare Earths 2009年第2期27卷 270-279页

作者： Nicodemus Michael A Salifu K francis jacobs douglass f Department of forestty and Natural Resources Hardwood Tree Improvement and Regeneration Center Purdue University West Lafayette IN 47907 USA

Rare earth elements have been used for 30 years in Chinese agriculture to improve growth and yield. Numerous scientific studies have shown improvements in physiology, mineral nutrition, and growth, though deleterious effects may also occur. Very few studies have been performed on woody species. We exponentially fertilized one-year old black walnut （Juglans nigra L.） seedlings with 0, 0.1, 1, 10, or 100 mg lanthanum （La） and 800 mg nitrogen （N） as NaNO3, （NH4）2SO4, NH4NO3, or no N. One month following final fertilization, growth, mineral nutrition, photosynthesis, chlorophyll, and nitrate reductase activity were assessed. Plants fertilized with the highest level of La had reduced fine root growth, concentrations of magnesium, calcium, nickel, and phosphorus, photosynthesis levels, and chlorophyll a content. foliar La concentration showed an interaction effect, with three to four times greater concentration in plants fed at 100 mg La to those given 10 mg La for （NH4）2SO4 and NHaNO3 treatments. The results suggested no beneficial effects of La addition at levels used in this study and interactions between N source and La levels did not have an important impact on the growth, mineral nutrition, or physiology of black walnut seedlings.

关键词： lanthanum nitrate reductase chlorophyll photosynthesis Jugians nigra rare earths

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Development of cork oak (Quercus suber L.) seedlings in response to tree shelters and mulching in northwestern Tunisia

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Journal of forestry Research 2013年第2期24卷 193-204页

作者： Taher Mechergui Marta Pardos Naceur Boussaidi Brahim Hasnaoui douglass f. jacobs faculté des Sciences de Bizerte (fSB) Instituto Nacional de Investigacion y Tecnologia Agraria y Alimentaria (INIA). Centro de Investigacion forestal. Ctra. de La Coruňa Institut Sylvo-Pastoral de Tabarka Department of forestry and Natural Resources Purdue University

The need for reforestation in cork oak （Quercus suber L.） areas is challenged by difficulties. Principal among these is herbivory of young plants, vegetative competition, and slow growth rates of cork oak seedlings. We evaluated the early development of cork oak seedlings treated using tree shelters and mulching in northwestern Tunisia. We tested three tree shelter treatments （non-vented, vented, and control） to shield seedlings from animal damage and five mulch types to control competing vegetation （Italian Stone Pine, Lentisk, combination of Italian Stone Pine and Lentisk （organic mulches）, gravel （inorganic mulch） and no mulch）. At the end of the two-year experiment, sheltered seedlings were 89-99% taller than unshelteredseedlings and had higher numbers and lengths of shoot growth flushes. In contrast, both stem diameter growth and dry weight biomass （from samples extracted after two years） were significantly reduced inside tree shelters. Root-to-shoot ratio was not significantly different in sheltered vs. unsheltered seedlings, suggesting that tree shelters do not adversely affect this parameter. Mulching alone did not favour growth, but could be beneficial when combined with tree shelters. The combination of vented tree shelters and gravel mulch was the most effective treatment for promoting diameter, height and stem volume growth.

关键词： Quercus suber L. afforestation tree shelter mulching seedling growth polycyclism

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OXIDATION Of A TWO-PHASE Cu-75Cr ALLOY IN AIRAT 700-900℃

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Acta Metallurgica Sinica(English Letters) 1997年第4期10卷 333-341页

作者： f. Gesmundo Y Niu f. Vianiand D.L. douglass(Universita di Genova, fiera del Mare, Pad. D,16129 Genova, Italy)(State Key Lab. for Corrosion and Protection, Institute of Corrosion and Protection of Metals, theChinese Academy of Sciences, Shenyang 110015, Ch Univ di Genova Genova Italy

The cormsion in air of a two-phase Cu-75Cr alloy was studied at 700-900℃. Thealloy cormded nearly parabolically at 700-800℃, but at 900℃ its instantaneousparabolic mte constant decreased with time. The scales were complex and consistedof an outermost layer of copper oxide generally followed bg a layer of the double ox-ide Cu2 Cr2 O4 sometimes containing particles of unoxidized chromium surmunded bya chromia layer. An innermost layer of chromia was also observed in some *** metallic copper was al8o frequently mixed with chromia particles. No Cr de-pletion was observed in the alloy close to the inteffoce with the scale. In any case,this alloy was not able to form an exclusive continuous protective chromia layer. Thespecial cormsion behavior Of this alloy is typical of two-phase binary systems with alange solubility gaP in which the outwaof dthesion fiux of the most-reactive componentin the alloy is strongly reduced and may be inswncient to fOrm a protective externallayer of the cormsponding oxide. In paTticular, the presence of particles of Cr withina double oxide layer is very unusual and is allowed only for the kinetic reason.

关键词： copper-chromium alloy two-phase oxidation

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Separation of a Signal of Interest from a Seasonal Effect in Geophysical Data:*** Nino/La Nina Phenomenon

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International Journal of Geosciences 2011年第4期2卷 414-419页

作者： David H.douglass Department of Physics and Astronomy University of RochesterRochesterUSA

Geophysical signals N of interest are often contained in a parent signal G that also contains a seasonal signal X at a known frequency fX. The general issues associated with identifying N and X and their separation from G are considered for the case where G is the Pacific sea surface temperature monthly data, SST3.4;N is the El Ni?o/La Ni?a phenomenon and the seasonal signal X is at a frequency of 1/(12 months). It is shown that the commonly used climatology method of subtracting the average seasonal values of SST3.4 to produce the widely used anomaly index Nino3.4 is shown not to remove the seasonal signal. furthermore, it is shown that the climatology method will always fail. An alternative method is presented in which a 1/fX (= 12 months) moving average filter f is applied to SST3.4 to generate an El Ni?o/La Ni?a index NL that does not contain a seasonal signal. Comparison of NL and Nino3.4 shows, among other things, that estimates of the relative magnitudes of El Ni?os from index NL agree with observations but estimates from index Nino3.4 do not. These results are applicable to other geophysical measurements.

关键词： El Nino/La Nina Climate Seasonal

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嵌入式与实时系统开发使用UML、对象技术、框架与模式 4

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丛书名：计算机科学丛书

2005年

作者：（美）Bruce Powel douglass 柳翔等译

本书重点介绍了使用统一建模语言进行基于模型的实时系统和嵌入式系统开发以及被称为ROPES的基于风险的迭代开发生命周期。

ISBN: (数字)7111155920

ISBN: (纸本)7111155920

本书重点介绍了使用统一建模语言进行基于模型的实时系统和嵌入式系统开发以及被称为ROPES的基于风险的迭代开发生命周期。

关键词：实时操作系统程序设计

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隐形飞机

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英语学习 1998年第4期 35-39页

作者：王桂琴 Steve douglass Bill Sweetman 清华大学

美国洛克希德·马丁公司生产的 f-117A夜鹰隐形战斗机是海湾战争的英雄,它深入敌后,百发百中地袭击巴格达的目标。夜鹰黑夜出击,所向披糜,但白昼却令它万般无奈,只好原地休息。就其速度和灵敏度而言,f-117夜鹰隐形战斗机都无法超出或躲... 详细信息

美国洛克希德·马丁公司生产的 f-117A夜鹰隐形战斗机是海湾战争的英雄,它深入敌后,百发百中地袭击巴格达的目标。夜鹰黑夜出击,所向披糜,但白昼却令它万般无奈,只好原地休息。就其速度和灵敏度而言,f-117夜鹰隐形战斗机都无法超出或躲避来袭的导弹,也无力予以还击,因为它只载有炸弹。这些局限性在黑夜里倒无关紧要,因其隐形机身设计可规避敌人的雷达监测。然

关键词：战斗机灯光系统隐形轰炸机飞行高度暴露距离实验站视觉传感器

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经济史上的结构和变革

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丛书名：汉译世界学术名著丛书·经济

1992年

作者：（美）诺思（North douglass C.）厉以平译

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