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Extended finite element-based cohesive zone method for modeling simultaneous hydraulic fracture height growth in layered reservoirs
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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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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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Response of photosynthesis,growth,and acorn mass of pedunculate oak to diff erent levels of nitrogen in wet and dry growing seasons
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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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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 JIANG Jian-hua ZHAO Qi-bing +4 位作者 LIU Qiang-ming CHEN Lan CHEN Fu-long QIAO Bao-jian HONG De-lin 《Rice science》 SCIE 2011年第3期196-203,共8页
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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关于改善中枢性性早熟患儿身高获益的思考
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作者 梁立阳 《中国当代儿科杂志》 CSCD 北大核心 2024年第1期19-24,共6页
随着遗传和环境等多种因素的改变,儿童性早熟的发病率逐渐增加,以改善身高为目的的性早熟治疗是临床关注的重点问题之一。目前,促性腺激素释放激素类似物(gonadotropin-releasing hormone analogs,GnRHa)仍是首选治疗药物,但其对身高的... 随着遗传和环境等多种因素的改变,儿童性早熟的发病率逐渐增加,以改善身高为目的的性早熟治疗是临床关注的重点问题之一。目前,促性腺激素释放激素类似物(gonadotropin-releasing hormone analogs,GnRHa)仍是首选治疗药物,但其对身高的改善作用受多种因素影响,可能导致身高获益低于预期。联合重组人生长激素(recombinant human growth hormone,rhGH)治疗是提高GnRHa疗效的可选治疗策略,然而联用时机等尚无明确推荐。基于性早熟治疗现状,重新审视单用GnRHa及联合rhGH治疗对身高的改善作用至关重要。该文探索了联合治疗适应证等策略,以期指导临床用药,帮助性早熟患儿实现更理想的身高获益。 展开更多
关键词 性早熟 身高获益 促性腺激素释放激素类似物 生长激素 儿童
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金亚蓓运用齐氏脐针治疗青少年身高增长缓慢的临床体会
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作者 姚莎娜 郑利芳 金亚蓓 《浙江中医药大学学报》 CAS 2024年第7期823-827,共5页
[目的]总结浙江省名中医金亚蓓教授运用齐氏脐针治疗青少年身高增长缓慢的临床经验与体会。[方法]通过临床跟诊、整理、回顾、分析的方式,从病因病机、辨证论治和特色选穴等方面总结金师运用脐针治疗青少年身高增长缓慢的临床经验,并附... [目的]总结浙江省名中医金亚蓓教授运用齐氏脐针治疗青少年身高增长缓慢的临床经验与体会。[方法]通过临床跟诊、整理、回顾、分析的方式,从病因病机、辨证论治和特色选穴等方面总结金师运用脐针治疗青少年身高增长缓慢的临床经验,并附验案两则。[结果]金师认为,青少年身高增长缓慢内在核心病机为“脾虚不运,五脏不坚”,与“肾虚不充,骨髓化生乏源”“肝失疏泄,横克脾土”关系密切。临床常将患者分为脾肾两虚型和肝郁脾虚型两类,脾肾两虚型患者的脐针治疗以“震位、巽位、离位、坤位”为主方,肝郁脾虚型则以“左升四针”为主,治疗过程中注重调畅情志,随证调整针方。文末所举验案中,其一患者属脾肾两虚型,用脐针益气健脾、补肾培元为治,兼顾患者负面情绪,辅以疏肝、祛邪、固脱,邪去正复后改为“左升四针”助阳升发而使身高得长;其二患者属肝郁脾虚型,系学业压力重大、肝失疏泄、横克脾土所致,以“左升四针”疏肝解郁、升发阳气,辅以宣肺理气,最终五脏调和而身高自长。[结论]金师运用齐氏脐针治疗青少年身高增长缓慢,严谨辨证,分型论治,关注患者心理状态,注重调畅情志,临床特色鲜明,治疗效果显著,其经验值得推广学习。 展开更多
关键词 脐针 青少年 身高增长缓慢 脾肾两虚 肝郁脾虚 名医经验 医案 金亚蓓
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升温情境中叶损对树木幼苗生长的影响
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作者 江政 邵剑文 任平 《热带亚热带植物学报》 CAS CSCD 北大核心 2024年第2期179-186,共8页
为探究升温能否在一定程度上抵消虫害叶损造成的负面影响,该研究采用控制变量法比较不同叶损程度下落叶松(Larix gmelinii)、红松(Pinus koraiensis)和冷杉(Abies fabri)幼苗当年的高生长以及来年不同温度下的萌芽情况。结果表明,当叶... 为探究升温能否在一定程度上抵消虫害叶损造成的负面影响,该研究采用控制变量法比较不同叶损程度下落叶松(Larix gmelinii)、红松(Pinus koraiensis)和冷杉(Abies fabri)幼苗当年的高生长以及来年不同温度下的萌芽情况。结果表明,当叶损程度达到50%时,落叶松幼苗当年的高生长会受到显著影响;而红松和冷杉在叶损程度达到75%时才会受到显著影响。室温下(13℃~18℃)落叶松来年的萌芽物候比20℃和25℃提前且高生长情况较好;红松和冷杉在室温下叶损75%会导致萌芽物候推迟且高生长受到影响,在20℃或25℃时,叶损造成的不利影响则会被削弱。因此,在未来变暖的情境中,推测红松和冷杉因虫害叶损造成的不利影响在一定程度上会被抵消,且对于虫害的抵抗和恢复亦明显高于落叶松。 展开更多
关键词 叶损 幼苗高生长 升温 红松 落叶松 冷杉
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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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中西医结合综合治疗特发性矮小症的临床价值分析
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作者 李丹丹 《中国实用医药》 2024年第4期163-165,共3页
目的探讨分析对特发性矮小症患儿采用中西医结合综合治疗的临床疗效。方法90例特发性矮小症患儿开展本次研究,将所有患儿根据数字表法分为观察组与对照组,各45例。单独给予西医治疗的为对照组,采用中西医结合综合治疗的为观察组。比较... 目的探讨分析对特发性矮小症患儿采用中西医结合综合治疗的临床疗效。方法90例特发性矮小症患儿开展本次研究,将所有患儿根据数字表法分为观察组与对照组,各45例。单独给予西医治疗的为对照组,采用中西医结合综合治疗的为观察组。比较两组的身高标准差及预测成年身高,消化系统及呼吸系统疾病的发生情况,生长因子水平。结果观察组身高标准差(-1.6±0.5)cm、预测成年身高(163.4±6.9)cm均优于对照组的(-1.9±0.7)、(156.7±5.4)cm(P<0.05)。观察组消化系统疾病发生率4.44%、呼吸系统疾病发生率8.89%均低于对照组的22.22%、28.89%(P<0.05)。观察组的胰岛素样生长因子-1为(195.5±25.8)ng/ml,胰岛素样生长因子结合蛋白-3为(4.4±0.8)μg/ml;对照组的胰岛素样生长因子-1为(104.5±16.8)ng/ml,胰岛素样生长因子结合蛋白-3为(2.4±0.4)μg/ml。观察组胰岛素样生长因子-1、胰岛素样生长因子结合蛋白-3均高于对照组(t=19.828、15.000,P=0.000、0.000<0.05)。结论对特发性矮小症患儿采用中西医结合综合治疗的临床疗效更为确切,可以使患儿的身高大幅增长,并提高患儿的自身免疫力,有必要在临床上大力推广。 展开更多
关键词 特发性矮小症 中西医结合 综合治疗 身高 生长因子
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水稻籼粳中间型杂交组合若干性状的遗传效应分析
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作者 李忠金 付思远 +4 位作者 陈萍萍 游月华 戴展峰 黄水明 彭玉林 《福建农业学报》 CAS CSCD 北大核心 2024年第5期522-531,共10页
【目的】水稻籼粳亚种间杂交具有强大的杂种优势已成为当前水稻育种关注的焦点,本研究旨在为籼粳交水稻育种实践以及水稻关键性状的遗传研究提供理论依据。【方法】按照NC-II不完全双列杂交方式,选择14个亲本材料并配组48个杂交组合,采... 【目的】水稻籼粳亚种间杂交具有强大的杂种优势已成为当前水稻育种关注的焦点,本研究旨在为籼粳交水稻育种实践以及水稻关键性状的遗传研究提供理论依据。【方法】按照NC-II不完全双列杂交方式,选择14个亲本材料并配组48个杂交组合,采用植物数量性状的加性-显性遗传模型(A-D模型)分析生育期、株高与粒形相关性状等共计5个农艺性状的遗传效应、杂种优势及性状之间的相关性。【结果】籼粳亚种间杂交稻生育期、株高、粒长、粒宽及长宽比等的加性方差分量占遗传主效应比率(V_(A)/V_(P))比值分别为69.2%、 74.2%、 58.9%、66.0%和63.5%。广义遗传率(H^(2)B)和狭义遗传率(H^(2)N)的变幅分别为59.0%~99.6%和69.2%~98.9%,均达显著或极显著水平,主要受加性效应控制,且受环境影响小,在育种上早期选择有效。大多数的籼粳亚种间杂种一代的生育期、株高和粒形性状均呈负向中亲优势和负向超亲优势,杂交后代的生育期缩短、株高降低,长宽比介于双亲之间。籼粳亚种间杂交稻生育期是一个独立遗传的品种特性,株高与粒形具呈显著正相关。【结论】在籼粳交育种上应关注生育期、株高,粒形等性状间的协调,有效利用杂种优势,培育强优势亚种间杂交稻新组合。 展开更多
关键词 水稻 籼粳交 生育期 株高 粒形 遗传效应
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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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1985—2019年中国18个少数民族17岁学生身高长期趋势分析
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作者 马云飞 李成跃 阿力木江·依米提·塔尔肯 《南京医科大学学报(自然科学版)》 CAS 北大核心 2024年第4期517-523,共7页
目的:分析1985—2019年我国18个少数民族17岁学生身高生长长期变化趋势。方法:提取7次中国学生体质与健康调研报告(除1991年)中蒙古族、回族、维吾尔族、壮族、朝鲜族、藏族、苗族、布依族、侗族、白族、土家族、哈尼族、傣族、傈僳族... 目的:分析1985—2019年我国18个少数民族17岁学生身高生长长期变化趋势。方法:提取7次中国学生体质与健康调研报告(除1991年)中蒙古族、回族、维吾尔族、壮族、朝鲜族、藏族、苗族、布依族、侗族、白族、土家族、哈尼族、傣族、傈僳族、佤族、纳西族、土族、羌族等18个少数民族学生身高均值进行研究。结果:34年间各少数民族男生17岁身高均值显著增长(P<0.05)。2019年18个少数民族17岁男学生中,回族男生身高均值最高(173.09 cm),苗族男生身高均值最低(162.66 cm),每10年身高增长>1 cm的民族有侗族(1.96 cm/10年)、白族(1.96 cm/10年)、土家族(1.95 cm/10年)、羌族(1.80 cm/10年)、回族(1.80 cm/10年)、蒙古族(1.79 cm/10年)、土族(1.72 cm/10年)、维吾尔族(1.63 cm/10年)、藏族(1.61 cm/10年)、布依族(1.55 cm/10年)、纳西族(1.52 cm/10年)、傣族(1.35 cm/10年)、傈僳族(1.29 cm/10年)、哈尼族(1.25 cm/10年)、壮族(1.16 cm/10年)、佤族(1.06 cm/10年);每10年身高增长<1 cm的民族是苗族(0.95 cm/10年)。2019年,18个少数民族17岁女学生中,回族女生身高均值最高(161.71 cm),布依族女生身高均值最低(151.63 cm),每10年身高增长>1 cm的民族分别是土家族(1.80 cm/10年)、回族(1.52 cm/10年)、土族(1.25 cm/10年)、白族(1.23 cm/10年)、侗族(1.18 cm/10年)、朝鲜族(1.12 cm/10年)、羌族(1.04 cm/10年);34年间除维吾尔族、苗族女生外,其余少数民族女生身高增长显著(P<0.05)。结论:我国少数民族男生均出现了较为明显的生长长期趋势,大部分少数民族女生出现了较为明显的生长长期趋势,各民族男女生身高增长不平衡,证明我国不同地区、不同少数民族学生生长潜力得以发挥,对于身高增长较慢的民族需要给予更高的关注,而对于那些身高增长较快的民族也要预防其带来的负面效应。 展开更多
关键词 少数民族 身高 生长长期趋势
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“天潜沔”地区杨树人工林胸径-树高生长模型研究 被引量:1
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作者 陈布凡 颜润芝 +3 位作者 何志杰 刘扬 刘伟 盛涛 《湖北林业科技》 2024年第1期6-10,65,共6页
以天门、潜江、仙桃地区杨树人工林为研究对象,通过2022年在该地区选取48块样地进行每木检尺,共测量731株杨树的生长量情况,作为建模数据。利用R软件对胸径-树高模型进行拟合,选用9个常用的胸径-树高模型。根据决定系数(R^(2))、均方根... 以天门、潜江、仙桃地区杨树人工林为研究对象,通过2022年在该地区选取48块样地进行每木检尺,共测量731株杨树的生长量情况,作为建模数据。利用R软件对胸径-树高模型进行拟合,选用9个常用的胸径-树高模型。根据决定系数(R^(2))、均方根误差(RMSE)、残差平均和(SSE)、平均绝对误差(MAE)、平均相对误差(MRE)和Akaike信息量准则(AIC)6个评价指标来确定最优模型,同时以天门、潜江、仙桃地区2021年立地条件、初植密度基本一致的10个杨树人工林固定样地的胸径、树高数据为检验数据,检验最优模型的预测能力。结果表明:在1~9号模型中,4号拟合效果最佳,其模型表达式为H=1.0410D-0.0122D^(2),可以作为天门、潜江、仙桃地区杨树人工林胸径-树高基础模型。 展开更多
关键词 杨树 胸径 树高 生长模型 天潜沔地区
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利用异速生长模型和博弈论解析藏川杨主干动态生长的遗传调控机制
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作者 危学达 王玉 +4 位作者 丁孟东 吴双 梁丹 叶梅霞 邬荣领 《北京林业大学学报》 CAS CSCD 北大核心 2024年第6期154-164,共11页
【目的】高度与直径是树木生命历程中的2个重要生长性状,本文通过量化藏川杨主干高度和直径之间的相互作用,探究这2个性状的生长过程和生长模式,揭示藏川杨主干动态生长的遗传调控机制。【方法】基于异速生长模型和博弈论构建藏川杨高... 【目的】高度与直径是树木生命历程中的2个重要生长性状,本文通过量化藏川杨主干高度和直径之间的相互作用,探究这2个性状的生长过程和生长模式,揭示藏川杨主干动态生长的遗传调控机制。【方法】基于异速生长模型和博弈论构建藏川杨高度与直径性状的动态生长互作微分方程,利用系统作图构建藏川杨主干生长遗传解析的统计模型。进一步以藏川杨自然群体作为研究材料,调查其在温室内的生长动态数据,结合本群体的高通量分子标记数据,开展藏川杨的全基因组基因定位工作。【结果】藏川杨主干高度和直径的整体生长曲线符合Logistic生长曲线,拆分整体生长曲线发现,藏川杨主干的直径生长对高度生长具有抑制作用,而高度生长对直径生长具有促进作用。所有藏川杨高度和直径的个体拟合优度> 0.90,且2个性状拟合的残差均服从随机分布,说明使用广义Lotka-Volterra微分方程来拟合藏川杨高度和直径效果很好。基于功能作图方法共定位到78个显著位点,可注释到52个候选基因。以2号染色体上最显著的SNP为例,对藏川杨高度和直径进行遗传解析,发现该SNP的3种基因型(AA、AC、CC)具有相似的高度–直径相互作用模式。该SNP对整体生长、独立生长和依赖生长发挥了不同方式的遗传效应。对定位到的显著位点进行功能注释,可将这些位点所在的基因分为:与木质素/细胞壁合成相关基因、与生长发育相关基因、与抗病抗逆性相关基因、与光合作用相关基因这4类。【结论】结合异速生长模型和博弈理论的基因定位模型,可检测基因如何通过合作或竞争策略来调控藏川杨主干的大小,识别树干动态生长的过程和模式,相关模型也可为其他物种重要性状之间的深层次遗传解析提供借鉴。 展开更多
关键词 藏川杨 博弈论 异速生长模型 高度 直径 数量性状位点
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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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南方典型红壤侵蚀区马尾松林立木生物量无人机遥感估测
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作者 田上峰 刘健 +2 位作者 余坤勇 王瑞璠 赵文凯 《西南林业大学学报(自然科学)》 CAS 北大核心 2024年第1期116-124,共9页
以南方典型红壤侵蚀区长汀县河田镇为例,结合无人机与激光雷达产生的点云数据优势,通过局部最大值和分水岭算法反演单木树高(H)和冠层半径(R_(c)),拟合以H和R_(c)为变量组合的异速生长方程,得到以新冠层参数为底的马尾松立木生物量模型... 以南方典型红壤侵蚀区长汀县河田镇为例,结合无人机与激光雷达产生的点云数据优势,通过局部最大值和分水岭算法反演单木树高(H)和冠层半径(R_(c)),拟合以H和R_(c)为变量组合的异速生长方程,得到以新冠层参数为底的马尾松立木生物量模型。结果表明:提取树高的决定系数(R^(2))和均方根误差(RMSE)分别为0.93和0.49 m;计算冠层半径的R2和RMSE分别为0.88和0.64 m;估算立木生物量的R^(2)和RMSE分别为0.89和3.37 kg。本研究通过无人机遥感影像定量参数并构建的异速生长方程中,以组合(H+R_(c))为底的异速生长方程估测马尾松林立木生物量的精度较高,可以有效估测马尾松林立木生物量,可为南方典型红壤侵蚀区马尾松林立木生物量准确估测提供参考。 展开更多
关键词 马尾松 红壤侵蚀区 立木生物量 生长方程 冠层半径 树高
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自制生长贴联合rhGH治疗儿童特发性矮身材的临床疗效观察
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作者 柏蕾 张连生 《襄阳职业技术学院学报》 2024年第2期109-112,共4页
目的探讨自制生长贴联合重组人生长激素(rhGH)对儿童特发性矮身材(ISS)的临床疗效。方法选取2022年1月至12月在襄阳市中医医院就诊的90例ISS患儿,随机分为对照组1、对照组2和实验组,每组30例。对照组1予以rhGH治疗,对照组2予以自制生长... 目的探讨自制生长贴联合重组人生长激素(rhGH)对儿童特发性矮身材(ISS)的临床疗效。方法选取2022年1月至12月在襄阳市中医医院就诊的90例ISS患儿,随机分为对照组1、对照组2和实验组,每组30例。对照组1予以rhGH治疗,对照组2予以自制生长贴治疗,实验组予以生长贴联合rhGH治疗,疗程均为12个月,比较三组治疗前、后身高和骨龄的变化情况。结果与治疗前相比,三组治疗后的身高值和骨龄均有明显增长(P<0.05);组间比较,三组的治疗效果相当(P>0.05)。治疗后实验组的生长速率明显快于两组对照组(P<0.05)。结论自制生长贴联合rhGH治疗儿童ISS能显著增高患儿身高,值得临床推广应用。 展开更多
关键词 自制生长贴 重组人生长激素 特发性矮身材 身高 骨龄
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根施不同植物生长调节剂对盆栽无花果株高和观赏性的影响
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作者 李林福 《果树资源学报》 2024年第3期63-66,共4页
【目的】降低盆栽无花果株高并提高其观赏性。【方法】以无花果波姬红为试材,萌芽展叶后根施不同浓度的多效唑、烯效唑和矮壮素溶液,研究不同处理对叶片生长、结果能力和嫩梢生长的影响。【结果】结果表明,根施3种植物生长调节剂后,均... 【目的】降低盆栽无花果株高并提高其观赏性。【方法】以无花果波姬红为试材,萌芽展叶后根施不同浓度的多效唑、烯效唑和矮壮素溶液,研究不同处理对叶片生长、结果能力和嫩梢生长的影响。【结果】结果表明,根施3种植物生长调节剂后,均降低了盆栽无花果叶长、叶宽、株高和冠幅,提高了叶绿素含量、单株结果数、单果质量、可溶性固形物质量分数和新梢基部粗度。【结论】不同处理中萌芽展叶后根施浓度40 mg/L烯效唑的综合效果最佳,建议在无花果盆景制作中参考应用。 展开更多
关键词 无花果 生长调节剂 株高 观赏性 应用
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