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Extended finite element-based cohesive zone method for modeling simultaneous hydraulic fracture height growth in layered reservoirs 被引量:1
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作者 Lei Yang Baixi Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第8期2960-2981,共22页
In this study,a fully coupled hydromechanical model within the extended finite element method(XFEM)-based cohesive zone method(CZM)is employed to investigate the simultaneous height growth behavior of multi-cluster hy... In this study,a fully coupled hydromechanical model within the extended finite element method(XFEM)-based cohesive zone method(CZM)is employed to investigate the simultaneous height growth behavior of multi-cluster hydraulic fractures in layered porous reservoirs with modulus contrast.The coupled hydromechanical model is first verified against an analytical solution and a laboratory experiment.Then,the fracture geometry(e.g.height,aperture,and area)and fluid pressure evolutions of multiple hydraulic fractures placed in a porous reservoir interbedded with alternating stiff and soft layers are investigated using the model.The stress and pore pressure distributions within the layered reservoir during fluid injection are also presented.The simulation results reveal that stress umbrellas are easily to form among multiple hydraulic fractures’tips when propagating in soft layers,which impedes the simultaneous height growth.It is also observed that the impediment effect of soft layer is much more significant in the fractures suppressed by the preferential growth of adjoining fractures.After that,the combined effect of in situ stress ratio and fracturing spacing on the multi-fracture height growth is presented,and the results elucidate the influence of in situ stress ratio on the height growth behavior depending on the fracture spacing.Finally,it is found that the inclusion of soft layers changes the aperture distribution of outmost and interior hydraulic fractures.The results obtained from this study may provide some insights on the understanding of hydraulic fracture height containment observed in filed. 展开更多
关键词 Hydraulic fracturing Layered reservoir Simultaneous height growth In situ stress Fracture spacing Extended finite element method(XFEM) Cohesive zone method(CZM)
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Study on height growth model of Pinus koraiensis 被引量:1
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作者 邓红兵 郝占庆 王庆礼 《Journal of Forestry Research》 SCIE CAS CSCD 2001年第3期192-194,210,共3页
Growth model is an efficient way to study growing process of some factors of plants quantitatively. Height growth of Korean pine (Pinus koraiensis) was studied by using Hyperbola equation, Logistic equation, Richards ... Growth model is an efficient way to study growing process of some factors of plants quantitatively. Height growth of Korean pine (Pinus koraiensis) was studied by using Hyperbola equation, Logistic equation, Richards equation with three parameters, and Richards equation with four parameters in this paper. The results showed that Richards equation with four parameters was the most suitable and could be turned into other theoretical equations when some parameters were given different value. The maximum height of trees could be given in advance when using Richards equation with four parameters, and it was even more corresponding to reality. In addition, a height growth model with real height of fixed age as a parameter was discussed in this paper. This kind of growth model could be used to calculate height growth of a given tree effectively. 展开更多
关键词 Korean pine height growth MODEL
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Comparative Analyses of Height Growth Velocities of School Boys in South Korea and Japan in the Past 50 Years
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作者 Hiroshi Mori 《Food and Nutrition Sciences》 2020年第7期659-668,共10页
The paper compares the height growth velocities of male schoolchildren in South Korea and Japan over the period 1961-2018. Growth in height was measured with the same birth cohorts, not by comparing mean height of asc... The paper compares the height growth velocities of male schoolchildren in South Korea and Japan over the period 1961-2018. Growth in height was measured with the same birth cohorts, not by comparing mean height of ascending ages in the same year. Starting from a lower economic base and mean height in the 1960s, high school males aged 17 in South Korea became 3 cm taller in mean height than their Japanese peers in the mid-2000s versus 2 - 3 cm shorter in the 1960s through 1970s. Children in Japan ceased to grow taller by the end of the 1980s, not because they quit taking more animal-sourced foods, meat and milk, but because they had drastically steered away from fruit and vegetables in their diets since the end of the 1970s. Having largely converged economically with Japan, South Korean children ceased to grow any taller in the mid-2000s. More importantly, it was discovered in this study that successive cohorts in South Korea started to fall gradually but steadily in height growth velocity from 1<sup><span style="font-family:Verdana;font-size:12px;">st</span></sup><span style="font-family:Verdana;font-size:12px;"> graders in middle school, aged 12 years to 3</span><sup><span style="font-family:Verdana;font-size:12px;">rd</span></sup><span style="font-family:Verdana;font-size:12px;"> graders in high school, </span><span style="font-family:Verdana;">and </span><span style="font-family:Verdana;">aged 17 years, to be once again 3 cm below their Japanese peers in the early-2010s. Analysis of Korea Household Expenditure Surveys classified by age groups of household head, decomposed by the author, revealed that children under 20 years of age in South Korea began to steer away from fruit and, particularly, vegetables in their at-home consumption in the mid-1990s, to average only 15% of the level of older adults in their 50s in the mid-2010s. These results lend supports to the importance of fruit and vegetables as determinants in height and its growth velocities in two genetically similar nations over time and stages of economic growth.</span> 展开更多
关键词 height School Boys growth Velocities Birth Cohort South Korea JAPAN Vegetables and Fruit
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Study of the Effects of Glucocorticoid on Growth and Adult Final Height in Children with Primary Nephrotic Syndrome
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作者 Fazhan Zhong Miao Zhang Yan Gao 《Open Journal of Nephrology》 2024年第1期1-9,共9页
Objective: To analyze the epidemiological characteristics of growth, as well as factors associated with growth retardation in children with primary nephrotic syndrome (PNS), and to investigate the effect of glucocorti... Objective: To analyze the epidemiological characteristics of growth, as well as factors associated with growth retardation in children with primary nephrotic syndrome (PNS), and to investigate the effect of glucocorticoid (GC) use duration on growth retardation in these children. Methods: Clinical and laboratory data of 353 PNS children treated at our hospital from July 2014 to June 2015 were collected through the medical record management system. Height, weight, and GC usage were recorded. Follow-up assessments were conducted in August 2022 for the original group, recording height, weight, and GC usage. Height and weight were evaluated using standard deviation scores (SDS). Categorical data were analyzed using chi-square test while continuous measurement data were analyzed using t-test or rank-sum test. Linear regression was used to assess the association between two single independent variables, and logistic regression analysis was used to screen for risk factors related to growth retardation in children with PNS. Results: Among the 353 PNS children enrolled in this study, male-to-female ratio of 2.64:1 (256 males vs 97 females). A total of 119 children exhibited growth retardation, incidence rate of 33.71%. The duration of GC usage among those with growth retardation was significantly longer compared to those without it (762.81 ± 934.50 days vs 263.77 ± 420.49 days;p Conclusion: PNS children treated with GC have a high incidence of growth retardation, and a high proportion of short stature in adulthood, especially in children with growth retardation in childhood, most of them have short stature after grown up. Time of GC usage is a risk factor for growth retardation in children with PNS. 展开更多
关键词 Primary Nephrotic Syndrome GLUCOCORTICOID CHILDREN growth Retardation Adult height
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Growth of HIV-Infected Children on Antiretrovirals Started Prior the Age of 2 Years
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作者 Anne Esther Njom Nlend Anita Tanekeu +2 位作者 Annie Carole Nga Motaze Jeannette Epée Ngoué Natacha Owona 《Open Journal of Pediatrics》 2025年第1期42-51,共10页
Objective: To study the effects of starting antiretroviral treatment (ART) prior the age of two years on the growth (height and weight) of HIV-infected children. Methodology: This was a retrospective cohort study. HIV... Objective: To study the effects of starting antiretroviral treatment (ART) prior the age of two years on the growth (height and weight) of HIV-infected children. Methodology: This was a retrospective cohort study. HIV-infected children on ART aged less than 15 years were divided into two groups Group 1 (G1) comprising children who started ART prior 2 years and Group (G2) those put on treatment thereafter. Main Measures: Percentage of children with growth retardation measured by Height for Age (H/A) and Weight for Age (W/A) Results: In total, we included 90 subjects. The median age was 10 years with a slight female predominance (51.2%). Most children were asymptomatic at the time of the study (96.6%), compliant with treatment (81%), 54.8% of children were on cotrimoxazole, 33% knew their status. At initiation, underweight was predominant in group 1 compared to group 2 (52% versus 29.5%;p = 0.015). Conversely, stunted growth predominated in G2 compared to G1 but without significant difference (38% versus 50%;p = 0.147). At the time of our study (median age of 10 years), catch-up height and weight predominated in G1 compared to G2;only a small proportion remained below −2SD (4% versus 18.2%;p = 0.015 and 9% versus 29.5%;p = 0.006 respectively for underweight and stunted growth). Conclusion and Global Health Implications: Growth retardation was common at ART initiation. Catch-up in height was more evident in the early treatment group. Initiation of ART before the age of 2 years rather influences children’s height than weight. The result of this study further emphasizes the need of early ART and closed clinical monitoring to better assess the impact of ART in areas with high rates of undernutrition. 展开更多
关键词 growth height and Weight HIV ANTIRETROVIRALS CHILDREN 2 Years Old
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Height/Length and Weight Growth Curves and Growth References of Children Aged 0 - 7 in Chongqing by GAMLSS
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作者 Qian Chen Jiaxiu Liu +1 位作者 Kaocong Tian Zhaohai Liu 《Health》 2020年第2期86-98,共13页
Aim: Using the generalised additive model for location, the scale and shape (GAMLSS), the standard of height (length), weight and percentage curve of children were formulated to understand the growth law in Chongqing ... Aim: Using the generalised additive model for location, the scale and shape (GAMLSS), the standard of height (length), weight and percentage curve of children were formulated to understand the growth law in Chongqing and to provide a reference for clinical and preventive health care work of paediatrics in West China. Methods: Data were collected from the health clinic dataset of children aged 0 - 7 years in the Department of Child Health Care of a Third-Class A hospital in Chongqing from 2010 to 2017. By applying the GAMLSS technology and taking D(μ, σ, ν, τ) as the specific distribution form, BCT as the link function, P-spline function and cubic splines function as the smoothing function, the unit value of age-specific standard deviation of height (length) and weight were obtained, and the percentile map was drawn. Results: Based on the principle of minimum AIC and SBC values, BCT distribution was chosen as the model of the link function. Fitting results of height (length) and weight parameters of boys and girls, standard deviation tables of age and percentile curves were obtained. Conclusions: This study was an exploration of using GAMLSS method to establish a reference value range in the field of children’s growth and development in China. It could supplement the relevant data of Chongqing area for Reference standard for growth and development of children under 7 years of age in China, and also provide a reference for the rational diagnosis of children’s short stature and malnutrition in Chongqing. 展开更多
关键词 CHILDREN height WEIGHT growth Curve GAMLSS
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Mining Applicable Elite Alleles of Growth Duration, Plant Height and Panicle Number per Plant by Conditional QTL Mapping in Japonica Rice 被引量:2
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作者 Jian-hua JIANG Qi-bing ZHAO +4 位作者 Qiang-ming LIU Lan CHEN Fu-long CHEN Bao-jian QIAO De-lin HONG 《Rice science》 SCIE 2011年第3期196-203,共8页
Unconditional and conditional QTL mapping were conducted for growth duration (GD), plant height (PH) and effective panicle number per plant (PN) using a recombinant inbred line (RIL) population derived from a cross be... Unconditional and conditional QTL mapping were conducted for growth duration (GD), plant height (PH) and effective panicle number per plant (PN) using a recombinant inbred line (RIL) population derived from a cross between two japonica rice varieties Xiushui 79 and C Bao. The RIL population consisted of 254 lines was planted in two environments, Nanjing and Sihong, Jiangsu Province, China. Results showed that additive effects were major in all of QTLs for GD, PH and PN detected by the two methods, and the epistatic effects explained a small proportion of phenotypic variation. No interactions were detected between additive QTL and environment, and between epistatic QTL pairs and environment. After growth duration was adjusted to an identical level, RM80-160bp was detected as an applicable elite allele for PN, with an additive effect of 0.71. When effective panicle number per plant was adjusted to an identical level, RM448-240bp was detected as an applicable elite allele for GD, with an additive effect of 4.64. After plant height was adjusted to an identical level, RM80-160bp was detected as an applicable elite allele for PN, with an additive effect of 0.62, and RM448-240bp was detected as an applicable elite allele for GD, with an additive effect of 3.89. These applicable elite alleles could be used to improve target traits without influencing the other two traits. 展开更多
关键词 japonica rice growth duration plant height effective panicle number per plant unconditional QTL mapping conditional QTL mapping recombinant inbred line
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Effects of Lithological Characters on the Growth of Cunninghamia lanceolata
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作者 刘映良 谢双喜 丁贵杰 《Agricultural Science & Technology》 CAS 2009年第6期94-96,107,共4页
Objective The aim was to reveal relationship between lithological character soil and productivity of Cunninghamia lanceolata and lay a foundation for systemic management of C. lanceolata fast-growing and high yield pl... Objective The aim was to reveal relationship between lithological character soil and productivity of Cunninghamia lanceolata and lay a foundation for systemic management of C. lanceolata fast-growing and high yield plantation. Method By using experimental ecology method and variance analysis, the biomass and growth of planting eleven years' C. lanceolata on the soils with six different lithologicel characters were studied. Result The effects of soils with six different lithological characters on the height, diameter growth and biomass of C. lanceolata were different, in which the growth order of C. lanceolata was: Feldspathic quartzy sandstone ( average height 523. 270 cm, average diameter 4.720 cm, average individual biomass 5.059kg) 〉 Basalt ( average height 511. 570 cm, average diameter 4.650 cm, average individual biomass 4.848 kg) 〉 Quartzy sandstone 〉 Blastopsammite 〉 The Quarternary Period red clay 〉 Coal-series siliceous sand-shale, and the difference was smaller between the last two lithological characters. Conclusion Feldspathic quartzy sandstone and Basalt are beneficial to C. lanceolata. 展开更多
关键词 Cunninghamia lanceolata Lithological character height growth Diameter growth BIOMASS
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促性腺激素释放激素类似物联合重组人生长激素治疗中枢性性早熟的成本-效果分析
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作者 杨春松 刘佳宁 +3 位作者 刘峥 曾力楠 吴瑾 张伶俐 《中国药房》 北大核心 2025年第1期79-85,共7页
目的比较促性腺激素释放激素类似物(GnRHa)联合重组人生长激素(rhGH)(联用方案)和GnRHa单药(单用方案)治疗中枢性性早熟(CPP)的长期经济性。方法从全社会角度出发,基于四川大学华西第二医院开展的真实世界研究,以终身高为效果指标,以202... 目的比较促性腺激素释放激素类似物(GnRHa)联合重组人生长激素(rhGH)(联用方案)和GnRHa单药(单用方案)治疗中枢性性早熟(CPP)的长期经济性。方法从全社会角度出发,基于四川大学华西第二医院开展的真实世界研究,以终身高为效果指标,以2022年我国农村及城镇居民人均可支配收入(20133~49283元)作为社会意愿支付(WTP)阈值,采用成本-效果分析法比较上述两种药物方案治疗CPP女孩的长期经济性。采用单因素敏感性分析和概率敏感性分析验证基础分析结果的稳健性,并通过情境分析比较不同长效制剂组合方案的经济性。结果基础分析结果显示,与单用方案相比,采用联用方案每增加CPP女孩1 cm终身高需多花费25193.49元;联用方案对于农村地区居民不具有经济性,但对于城镇地区居民具有经济性。单因素敏感性分析结果显示,对基础分析结果可能产生影响的不确定因素主要为rhGH价格、联用方案组患儿终身高、联用方案组rhGH治疗时间、单用方案组患儿终身高。概率敏感性分析结果显示,当WTP阈值大于26010元/cm时,联用方案具有经济性的概率均高于单用方案。情境分析结果显示,当使用GnRHa长效制剂时,每3个月肌内注射1次的联用方案对于农村地区居民不具有经济性,但对于城镇地区居民具有经济性;当使用rhGH长效制剂时,每周皮下注射1次的联用方案对于农村地区和城镇地区居民均不具有经济性。结论推荐家庭经济负担能力相对较强的CPP患儿在GnRHa治疗的基础上额外联用rhGH来改善终身高;应考虑治疗的获益、风险和可负担性,避免盲目追求身高增长而滥用rhGH。 展开更多
关键词 中枢性性早熟 促性腺激素释放激素类似物 重组人生长激素 身高 药物经济学 成本-效果分析
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Effect of first thinning and pruning on the individual growth of Pinus patula tree species 被引量:4
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作者 Edward Missanjo Gift Kamanga-Thole 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第4期827-831,共5页
The effect of first thinning and pruning on height, diameter at breast height (DBH), and volume growth was studied in individual trees of Pinus patula Schiede and Deppe in Chongoni Plantation, using four plots for t... The effect of first thinning and pruning on height, diameter at breast height (DBH), and volume growth was studied in individual trees of Pinus patula Schiede and Deppe in Chongoni Plantation, using four plots for thinning trials. Each of the plots was 0.5 ha and subjected to one of the fol- lowing silvicultural treatments: first thinning and pruning, first thinning and no pruning, pruning and no thinning, and control (no pruning and no thinning). The silvicultural treatments were randomized in four replicates. Fourteen years after planting, the following parameters were measured including total height, DBH, and volume. The highest DBH and volume growth was observed in thinning and pruning, while the highest growth in height was observed where there was pruning and no thinning. Clearly, both thinning and pruning are an important manage- ment option in pine species plantations in Malawi to maximize the increase in volume productivity. 展开更多
关键词 Pinus patula Thinning and pruning Diameter growth height growth VOLUME
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1985—2019年中国汉族7~18岁儿童青少年生长发育长期趋势分析
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作者 米尔扎克木·肉孜 阿力木江·依米提·塔尔肯 《中国健康教育》 北大核心 2025年第2期128-132,137,共6页
目的了解中国1985—2019年7~18岁儿童青少年生长发育长期趋势,为制定干预措施提供理论参考。方法选取1985、1991、1995、2000、2005、2010、2014和2019年共8次全国学生体质与健康调研中的7~18岁汉族儿童青少年的身高、体重和身体质量指... 目的了解中国1985—2019年7~18岁儿童青少年生长发育长期趋势,为制定干预措施提供理论参考。方法选取1985、1991、1995、2000、2005、2010、2014和2019年共8次全国学生体质与健康调研中的7~18岁汉族儿童青少年的身高、体重和身体质量指数(BMI)数据,计算各阶段的增幅和每10年增速,对平均值进行加权线性回归检验趋势变化。结果1985—2019年,各年龄组男女生的身高、体重和BMI均呈上升趋势(P<0.05)。以1985—2000年为第1阶段,2000—2010年为第2阶段,2010—2019年为第3阶段,身高每10年增速第1阶段>第3阶段>第2阶段,体重每10年增速第3阶段>第1阶段>第2阶段,BMI每10年增速第3阶段>第1阶段>第2阶段,且男生增速普遍大于女生。1985—2019年中国汉族7~18岁儿童青少年的身高、体重和BMI发育高峰年龄持续提前(P<0.05),2019年的身高、体重和BMI发育高峰年龄分别比1985年提前了1.09、1.22和2.60岁。结论34年来,中国汉族7~18岁儿童青少年身高、体重和BMI持续增长,发育高峰年龄提前。近10年身高增速放缓,体重和BMI增速加快,男生增速大于女生。 展开更多
关键词 儿童青少年 身高 体重 生长发育
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Growth and ecophysiology of seedlings of Podocarpus falcatus in plantations of exotic species and in a natural montane forest in Ethiopia 被引量:1
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作者 Desalegn Tadele Masresha Fetene 《Journal of Forestry Research》 SCIE CAS CSCD 2013年第1期29-35,共7页
The potential role of exotic tree plantations in facilitating successional processes on degraded areas was evaluated in southern Ethiopia by comparing seedling characteristics, transpiration and photosynthetic perform... The potential role of exotic tree plantations in facilitating successional processes on degraded areas was evaluated in southern Ethiopia by comparing seedling characteristics, transpiration and photosynthetic performance of Podocarpus falcatus seedlings in Eucalyptus plantation, Pinus plantation, adjacent natural forest and clear-felled plantation site. P. falcatus seedlings exhibited differences in architecture between Eucalyptus and Pinus plantations. They had higher leaf area, shorter internode length and greater number of lateral branches in Eucalyptus plantation. At similar vapor pressure deficit (VPD), P. falcatus transpired much less than E. saligna, especially at higher VPDs. Analysis of fluorescence parameters in the leaves showed no significant differences in the level of dark-adapted and light-adapted fluorescence yield (Fv/Fm and ΔF/Fm′, respectively), electron transport rate (ETR) and nonphotochemical quenching (NPQ) among seedlings grown inside plantations and adjacent natural forest, indicating similar photosynthetic performance. Nevertheless, there was evidence of photoinhibition in P. falcatus in the clear-felled site which had low fluorescence yield but high values of NPQ as protection from photoamage. The light response curves of ETR, NPQ and ΔF/Fm′ showed similar light saturation behavior among the seedlings grown inside plantations and natural forest and suggested a sequence of light-adapted to shade-adapted behavior in Natural forest 〉 Eucalyptus plantation 〉 Pinus plantation. The results show the structural flexibility, better water-use and adaptability of P. falcatus in its use of the understory environment of plantation species. 展开更多
关键词 chlorophyll fluorescence height growth lateral growth light response curves TRANSPIRATION
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Response of photosynthesis,growth,and acorn mass of pedunculate oak to diff erent levels of nitrogen in wet and dry growing seasons 被引量:1
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作者 Krunoslav Sever Saša Bogdan ŽeljkoŠkvorc 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第1期167-176,共10页
The objective was to examine the effects of optimal leaf nitrogen levels>2.0%and suboptimal levels<2.0%,nitrogen nutrition on net photo synthetic rate,stem diameter increment,height growth increment and acorn ma... The objective was to examine the effects of optimal leaf nitrogen levels>2.0%and suboptimal levels<2.0%,nitrogen nutrition on net photo synthetic rate,stem diameter increment,height growth increment and acorn mass of pedunculate oak during 2010 in the absence of drought stress and during 2011 under the impact of moderate drought stress.According to the results,moderate drought stress significantly reduced net photo synthetic rate,stem diameter increment and height growth increment,while acorn mass was not affected.Suboptimal nitrogen nutrition significantly reduced the net photo synthetic rate and stem diameter increment only in the wet year,acorn mass in both wet and dry years,while height growth increment was not significantly reduced by suboptimal nitrogen nutrition in either year.The results indicate that optimal nitrogen levels can stimulate photo synthetic rate and stem diameter increment of pedunculate oak only in the absence of moderate drought stress.Moreover,the results show that moderate drought stress is a more dominant stressor for photosynthesis and growth of pedunculate oak than suboptimal nitrogen nutrition,while for acorn development,it is the more dominant stressor. 展开更多
关键词 Quercus robur L. Drought stress Net photosynthic rate Stem diameter increment height growth increment Acorn mass
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Impacts of Primo MAXX Growth Regulator on the Growth of Bermuda Grass
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作者 李战胜 张海娟 陈勇 《Agricultural Science & Technology》 CAS 2010年第9期180-182,共3页
[Objective] The aim was to investigate the effects of Primo MAXX growth regulator on growth of Bermuda grass,explore appropriate application concentration of Primo MAXX on Bermuda grass,and provide basis for the appli... [Objective] The aim was to investigate the effects of Primo MAXX growth regulator on growth of Bermuda grass,explore appropriate application concentration of Primo MAXX on Bermuda grass,and provide basis for the application of Primo MAXX in Bermuda meadow.[Method]The height,leaf colour and the aerial part's fresh weight of Bermuda grass treated with different concentrations were researched using single factor random block test.[Result]Primo MAXX application effectively reduced the height in all treatment without significant difference;appropriate application of Primo MAXX can enrich the color;and 35 days after application,Bermuda grass roots were become thicker.[Conclusion]The application of Primo MAXX with effective dose of 150-300 g/hm2 on Bermuda grass in southern China is more appropriate. 展开更多
关键词 Primo MAXX Bermuda grass growth height Leaf color Fresh weight of aerial part
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GROWTH OF MONGOLIAN OAK
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作者 赵惠勋 王传宽 刘滨辉 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1994年第1期10-17,共8页
The height fast growing period of oak seedling (Quercus mongolica) was between 25 to 30 years old but the diameter varied greatly. The maximum diurnal height increment of the investigated oak tree reached 3. 3 cm, but... The height fast growing period of oak seedling (Quercus mongolica) was between 25 to 30 years old but the diameter varied greatly. The maximum diurnal height increment of the investigated oak tree reached 3. 3 cm, but at daytime it was much greater than at night. The oak trees usually sprouted twice and even treble in the growing season. In natural oak stands. the volume rarely exceeded 200 m3/hm2 and the mean volume increment was only about 2 m3/hm2 展开更多
关键词 Mongolian oak Grand period of growth Seasonal growth Diurnal height growth Stand growth
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不同生长激素对白刺硬枝扦插育苗的影响
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作者 鲁国瑜 姜生秀 +3 位作者 张莹花 赵鹏 张裕年 张逸君 《防护林科技》 2025年第2期13-16,共4页
以白刺1~2年生枝条为材料进行硬枝扦插试验,探讨不同质量浓度萘乙酸(NAA)、吲哚丁酸(IBA)和吲哚乙酸(IAA)对插条当年成活率和生长状况的影响。结果表明:从成活率看,NAA质量浓度为200 mg·L^(-1),IBA质量浓度为50、100、200 mg·... 以白刺1~2年生枝条为材料进行硬枝扦插试验,探讨不同质量浓度萘乙酸(NAA)、吲哚丁酸(IBA)和吲哚乙酸(IAA)对插条当年成活率和生长状况的影响。结果表明:从成活率看,NAA质量浓度为200 mg·L^(-1),IBA质量浓度为50、100、200 mg·L^(-1),IAA质量浓度为50、200 mg·L^(-1)时,有助于提高白刺硬枝扦插成活率;从生长情况看,NAA质量浓度为50、100、200 mg·L^(-1),IBA为50、200 mg·L^(-1),IAA为50、100 mg·L^(-1)时,促进白刺营养生长。综合考虑因素间交互作用,促进白刺硬枝扦插成活生长最佳处理为NAA质量浓度为200 mg·L^(-1)处理,成活率达58.75%,苗高13.14 cm,冠幅10.08 cm。 展开更多
关键词 白刺 生长激素 成活率 苗高
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不同造林模式下2个树种在矿山迹地植被修复中的表现研究
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作者 严毅 金智伟 +3 位作者 杨利明 铁筱睿 李天禄 徐钡昌 《林业调查规划》 2025年第1期30-33,39,共5页
为了解不同树种、不同造林模式在矿山迹地植被修复中造林成活率、保存率及初期生长表现,在昆明市海口林场废弃磷矿山进行了2个树种、3种造林模式的造林试验。结果表明,不同造林模式造林成活率和保存率差异极显著(P<0.01),华山松的造... 为了解不同树种、不同造林模式在矿山迹地植被修复中造林成活率、保存率及初期生长表现,在昆明市海口林场废弃磷矿山进行了2个树种、3种造林模式的造林试验。结果表明,不同造林模式造林成活率和保存率差异极显著(P<0.01),华山松的造林成活率(100%)远高于滇青冈(89.76%),2个树种纯林的保存率远大于混交林的保存率;不同造林模式下林分生长量之间树高差异极显著(P<0.01)、地径生长量之间差异显著(0.01<P<0.05),滇青冈表现出较高的树高生长量(混交林30.83 cm,纯林17.10 cm),华山松树高生长量均不高(纯林0.64 cm、混交林0.52 cm);滇青冈纯林和混交林地径生长量表现适中(纯林0.64 cm、混交林0.52 cm),而华山松纯林和混交林地径生长量表现出两个极端(纯林0.83 cm、混交林0.47 cm);2个树种造林保存率与地径生长量呈极显著正相关,树高生长量与地径生长量呈显著负相关。认为华山松和滇青冈在矿山迹地植被修复中有很强的适应性,不同造林模式对造林成活指标和生长指标影响较大;综合多性状评价,滇青冈混交林成效最好,其次为华山松纯林、滇青冈纯林,华山松混交林成效最差。 展开更多
关键词 造林模式 矿山迹地 植被修复 华山松 滇青冈 树高生长量 成活率
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平茬高度对杜香生长及其光合生理和次生代谢产物积累的影响
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作者 邱志濠 赵亭亭 +1 位作者 苑晓彤 杨逢建 《东北林业大学学报》 北大核心 2025年第4期55-60,共6页
以3年生杜香(Rhododendron tomentosum)为研究对象,在黑龙江省大兴安岭地区呼中区林场内,选取林相整齐、坡面相对均匀的林分,随机设置3个20 m×20 m的平行样地,在各样地内根据五点取样法各设置5个1.0 m×1.0 m小样地;2022年6月3... 以3年生杜香(Rhododendron tomentosum)为研究对象,在黑龙江省大兴安岭地区呼中区林场内,选取林相整齐、坡面相对均匀的林分,随机设置3个20 m×20 m的平行样地,在各样地内根据五点取样法各设置5个1.0 m×1.0 m小样地;2022年6月30日,在样地内随机挑选4个小样地,各选取长势一致的10株杜香设置4个处理组(平茬高度分别为10、15、20 cm的3个处理组,未平茬的1个对照组);按照试验设计,测定杜香植株萌芽及叶片生长、叶片气体交换参数、叶片光合色素质量分数、叶片次生代谢产物质量分数,分析平茬高度对杜香生长、光合生理及次生代谢产物的影响。结果表明:(1)平茬使杜香侧枝、叶片生长得到促进,萌发枝条能力比对照组显著增强。其中,平茬高度为20 cm的处理组,侧枝长度、萌发数量最高;平茬高度为15 cm的处理组,成枝数量、叶宽、叶干质量,显著高于其他组。(2)平茬处理后,杜香的净光合速率、蒸腾速率、气孔导度、水分利用效率,均呈现出先升高后降低的趋势,其中平茬高度为15 cm的处理组的这4个指标显著高于其他组。与对照组相比,平茬处理后叶光合色素的质量分数显著提高。(3)平茬处理后,杜香叶片中的总酚、类黄酮质量分数均高于对照组;平茬处理后,杜香叶片中的精油质量分数显著低于对照组,各平茬处理组差异不显著。(4)综合研究结果,说明平茬处理能够促进杜香萌芽和生长,通过提升杜香的光合色素质量分数和气体交换能力,进而增强其光合效率,同时调节次生代谢产物的质量分数,以适应平茬处理带来的影响。 展开更多
关键词 杜香 生长 光合生理 次生代谢产物 平茬高度
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Crohn's disease and growth deficiency in children and adolescents 被引量:8
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作者 Marco Gasparetto Graziella Guariso 《World Journal of Gastroenterology》 SCIE CAS 2014年第37期13219-13233,共15页
Nutritional concerns, linear growth deficiency, and delayed puberty are currently detected in up to 85% of patients with Crohn's disease(CD) diagnosed at childhood. To provide advice on how to assess and manage nu... Nutritional concerns, linear growth deficiency, and delayed puberty are currently detected in up to 85% of patients with Crohn's disease(CD) diagnosed at childhood. To provide advice on how to assess and manage nutritional concerns in these patients, a Medline search was conducted using "pediatric inflammatory bowel disease", "pediatric Crohn's disease", "linear growth","pubertal growth", "bone health", and "vitamin D" as key words. Clinical trials, systematic reviews, and metaanalyses published between 2008 and 2013 were selected to produce this narrative review. Studies referring to earlier periods were also considered if the data was relevant to our review. Although current treatment strategies for CD that include anti-tumor necrosis factor-αtherapy have been shown to improve patients' growth rate, linear growth deficiencies are still common. In pediatric CD patients, prolonged diagnostic delay, high initial activity index, and stricturing/penetrating typeof behavior may cause growth deficiencies(in weight and height) and delayed puberty, with several studies reporting that these patients may not reach an optimal bone mass. Glucocorticoids and inflammation inhibit bone formation, though their impact on skeletal modeling remains unclear. Long-term control of active inflammation and an adequate intake of nutrients are both fundamental in promoting normal puberty. Recent evidence suggests that recombinant growth factor therapy is effective in improving short-term linear growth in selected patients, but is of limited benefit for ameliorating mucosal disease and reducing clinical disease activity. The authors conclude that an intense initial treatment(taking a "top-down" approach, with the early introduction of immunomodulatory treatment) may be justified to induce and maintain remission so that the growth of children with CD can catch up, ideally before puberty. Exclusive enteral nutrition has a key role in inducing remission and improving patients' nutritional status. 展开更多
关键词 Bone health Enteral nutrition growth height Pediatric inflammatory bowel disease Pediatric Crohn's disease Linear growth Pubertal growth Vitamin D Weight loss
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Growth of Scotch Pine (Pinus sylvestris L.) Plantation in Northern Mongolia 被引量:2
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作者 S. Gerelbaatar N. Baatarbileg 《Journal of Agricultural Science and Technology(B)》 2011年第8期1205-1210,共6页
The growth of Scotch pine in Northem Mongolian plantations was studied to determine variation in heights, diameters at breast height (DBH), and main and annual volume increment of stem volumes in relation to plantat... The growth of Scotch pine in Northem Mongolian plantations was studied to determine variation in heights, diameters at breast height (DBH), and main and annual volume increment of stem volumes in relation to plantation age. The study was conducted in the Tujyin Nars region, where six plantations ranging from 9 to 25 years old were selected for the assessment. Results indicate that the growth of Scotch pine on the plantations did not vary by site, and that more intensive annual increment in height was observed on Scotch pine plantations between the ages of 8 to 15 years. The amount of annual height increment and radial growth improves regularly up to 9 to 11 years of age and then the intensity of annual increment declines due to competition for light and nutrients. Additionally, there was a reduction in the number of trees per ha. Results suggest that it is necessary to implement forestry thinning which aimed at improving growth of Scotch pine on the plantations because intensity of annual increment in height and diameter reduces regularly due to restriction of growing condition. 展开更多
关键词 SEEDLING annual increment height and radial growth volume survival.
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