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Eff ects of stand condition and root density on fi ne-root dynamics across root functional groups in a subtropical montane forest 被引量:1
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作者 Lin Huang Rudong Zhao +3 位作者 Xiaoxiang Zhao Qiuxiang Tian Pengyun Yue Feng Liu 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第3期665-675,共11页
Fine roots play key roles in belowground C cycling in terrestrial ecosystems.Based on their distinct functions,fi ne roots are either absorptive fi ne roots(AFRs)or transport fi ne roots(TFRs).However,the function-bas... Fine roots play key roles in belowground C cycling in terrestrial ecosystems.Based on their distinct functions,fi ne roots are either absorptive fi ne roots(AFRs)or transport fi ne roots(TFRs).However,the function-based fi ne root dynamics of trees and their responses to forest stand properties remain unclear.Here,we studied the dynamics of AFRs and TFRs and their responses to stand conditions and root density in a subtropical montane mixed forest based on a 2-a root window experiment.Mean(±SE)annual production,mortality,and turnover rate of AFRs were 7.87±0.17 m m^(−2)a^(−1),8.13±0.20 m m^(−2)a^(−1)and 2.96±0.24 a^(−1),respectively,compared with 7.09±0.17 m m^(−2)a^(−1),4.59±0.17 m m^(−2)a^(−1),and 2.01±0.22 a^(−1),respectively,for TFRs.The production and mortality of fi ne roots were signifi cantly higher in high root-density sites than in low-root density sites,whereas the turnover of fi ne roots was faster in the low root-density sites.Furthermore,root density had a larger positive eff ect than other environmental factors on TFR production but had no obvious impact on AFR production.Tree species diversity had an apparent positive eff ect on AFR production and was the crucial driver of AFR production,probably due to a complementary eff ect,but had no evident impact on TFR.Both tree density and tree species diversity were positively correlated with the mortality of AFRs and negatively related to the turnover of TFRs,suggesting that higher root density caused stronger competition for rooting space and that plants tend to reduce maintenance costs by decreasing TFR turnover.These fi ndings illustrated the importance of root functional groups in understanding root dynamics and their responses to changes in environmental conditions. 展开更多
关键词 root functional group root production root mortality root turnover Stand condition Badagongshan mountain
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APPROXIMATE SOLUTION OF A p-th ROOT FUNCTIONAL EQUATION IN NON-ARCHIMEDEAN (2,β)-BANACH SPACES
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作者 Iz-iddine EL-FASSI Hamid KHODAEI Themistocles M.RASSIAS 《Acta Mathematica Scientia》 SCIE CSCD 2019年第2期369-381,共13页
In this paper, using the Brzdek's fixed point theorem [9,Theorem 1] in non-Archimedean(2,β)-Banach spaces, we prove some stability and hyperstability results for an p-th root functional equation ■where p∈{1, …... In this paper, using the Brzdek's fixed point theorem [9,Theorem 1] in non-Archimedean(2,β)-Banach spaces, we prove some stability and hyperstability results for an p-th root functional equation ■where p∈{1, …, 5}, a_1,…, a_k are fixed nonzero reals when p ∈ {1,3,5} and are fixed positive reals when p ∈{2,4}. 展开更多
关键词 fixed point theorem p-th root functional equation stability NON-ARCHIMEDEAN (2 β)-normed SPACES
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Exploring plant adaptation strategies to phosphorus limitation induced by nitrogen addition:foliar phosphorus allocation and root functional traits analysis in two dominant subalpine tree species 被引量:1
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作者 Yan Su Yongfeng Tang +3 位作者 Yi Hu Meiyu Liu Xuyang Lu Baoli Duan 《Journal of Plant Ecology》 SCIE CSCD 2024年第4期154-166,共13页
Plants adapt to the limitation of soil phosphorus(P)induced by nitrogen(N)deposition through a complex interaction of various root and leaf functional traits.In this study,a pot experiment was conducted to explore the... Plants adapt to the limitation of soil phosphorus(P)induced by nitrogen(N)deposition through a complex interaction of various root and leaf functional traits.In this study,a pot experiment was conducted to explore the effects of different levels of N addition(control,low N[LN]:25 kg N ha^(-1) yr^(-1),high N[HN]:50 kg N ha^(-1) yr^(-1))on tree growth,leaf nutrient content,foliar P fractions and root characteristics of two dominant tree species,the pioneer species Salix rehderiana Schneid and the climax species Abies fabri(Mast.)Craib,in a subalpine forest in southwestern China.The results demonstrated that LN addition had a minimal impact on leaf N and P contents.Conversely,HN addition significantly decreased the leaf P content in both species.Salix rehderiana exhibited more pronounced increases in specific root length and specific root area under P deficiency triggered by HN addition when compared with A.fabri.In contrast,A.fabri showed weaker morphological responses to N addition but had a higher proportion of foliar P to metabolic P,as well as higher root exudates rate and root phosphatase activity in response to HN addition.Abies fabri employs a synergistic approach by allocating a greater amount of leaf P to metabolite P and extracting P from the soil through P-mobilizing exudates and root phosphatase activity,while S.rehderiana exhibits higher flexibility in modifying its root morphology in response to P limitation induced by HN addition.This study provides insights into subalpine tree species adaptation to N-induced P limitation,emphasizing its significance for guiding forest management and conservation in the context of global climate change. 展开更多
关键词 N deposition root functional traits root morphology root exudation P-scavenging strategy
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Single-cell nuclear transcriptomics reveal root tip adaptations to nitrogen scarcity in wheat
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作者 Chuangbei Hai Yan Li +2 位作者 Chaojun Peng Lin Hu Weigang Xu 《The Crop Journal》 2025年第4期1156-1167,共12页
Roots play a critical role in acquisition and utilization of nitrogen in wheat,influencing nitrogen use efficiency(NUE),and ultimately determining yield.However,the detailed responses of root tips to fluctuations in n... Roots play a critical role in acquisition and utilization of nitrogen in wheat,influencing nitrogen use efficiency(NUE),and ultimately determining yield.However,the detailed responses of root tips to fluctuations in nitrogen availability and the underlying regulatory mechanisms enabling adaptation to nitrogenlimited conditions,remain elusive.In this study,we used single-cell nuclear transcriptomics of the highnitrogen utilization variety(HNV)Zhengmai 1860(ZM1860)to construct a comprehensive map of root tip cells under both controlled and nitrogen starvation(N-starv)conditions.Identification of various cell types and their associated genes highlighted the diversity of cellular processes.Using single-nucleus consensus weighted gene co-expression network analysis(hdWGCNA),we identified key modules central to nitrogen metabolism.These identified the prominent role of epidermal cells(EC).The gene TaGS1.2,which is involved in glutamine synthesis,exhibited increased expression under nitrogen-deficient conditions,validating its functional significance in nutrient acquisition.Serving as a key functional gene that adapts to nitrogen-deficient conditions this gene also positively regulated root development.Analysis of the transcriptional regulatory network in EC further revealed the pivotal role of TaG S1.2 in the nitrogen metabolism network.We also uncovered mechanisms that enhance cell-to-cell communication in nitrogen-deficient environments by identifying specific receptors.Single-cell nuclear transcriptome mapping offers valuable insights into the complex responses of root tip cells to nitrogen scarcity and guides future breeding strategies aimed at developing more nitrogen-efficient wheat varieties. 展开更多
关键词 Single-nucleus RNA-seq root function Nitrogen scarcity Epidermal cell
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Approximate solution of an advanced reciprocal-radical functional equation
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作者 Hemen Dutta B.V.Senthil Kumar S.Suresh 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第3期701-708,共8页
The significant role of square root mapping in probability,statistics,physics,architecture and engineering motivates us to emphasize on a new radical functional equation arising from a square root and reciprocal squar... The significant role of square root mapping in probability,statistics,physics,architecture and engineering motivates us to emphasize on a new radical functional equation arising from a square root and reciprocal square root mappings.The interesting attribute of this equation is that it has both a square root mapping and a reciprocal square root mapping as solutions.We establish that the hyperstabilities of this equation exist using a fixed point alternative theorem.It is also demonstrated with an example that the stability may fail in special cases. 展开更多
关键词 square root function radical function reciprocal-radical function Ulam-Hyers stability
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Nonexistence of Iterative Roots on PM Functions 被引量:1
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作者 Lin LI Xiaohua LIU Liu LIU 《Journal of Mathematical Research with Applications》 CSCD 2013年第2期204-208,共5页
Many results are given for iterative roots of PM functions, a class of non-monotonic continuous functions, when the characteristic interval exists. In this paper we discuss iterative roots in the opposite case and par... Many results are given for iterative roots of PM functions, a class of non-monotonic continuous functions, when the characteristic interval exists. In this paper we discuss iterative roots in the opposite case and partly answer the Open Problem 1 proposed in [Ann. Polon. Math., 1997, 65(2): 119-128]. 展开更多
关键词 iterative root PM function fort.
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A Study of Factors Inducing Root Resorption During Functional Occlusion in Pre-orthodontic Patients 被引量:1
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作者 Sahibzadi Uzma Noor Lu Yanqin Xia Shuchi Jian Xinchun 《口腔医学研究》 CAS CSCD 北大核心 2009年第2期226-229,共4页
目的:研究未经正畸治疗的前牙有牙根吸收和无牙根吸收的错患者的及功能特征,揭示引起牙根吸收的可能的及咬合因素,为正畸治疗治疗前已有牙根吸收的患者提供可能的及功能参照标准。方法:用曲面断层片作为筛查方法,并用根尖... 目的:研究未经正畸治疗的前牙有牙根吸收和无牙根吸收的错患者的及功能特征,揭示引起牙根吸收的可能的及咬合因素,为正畸治疗治疗前已有牙根吸收的患者提供可能的及功能参照标准。方法:用曲面断层片作为筛查方法,并用根尖片进一步确诊根尖吸收,对07年7月至08年3月在我正畸科初诊的患者进行调查,从中选择14名前牙根尖吸收为Ⅱ~Ⅲ度的错畸形患者作为研究组,用年龄和性别作为控制标准随机选择14名无根尖吸收的错畸形患者作为对照组,采用临床检查、模型分析和DenarMarkⅡ架分析的方法研究两组的和功能特征,用spss14.0进行t检验统计分析。结果:两组的特征不存在差异,临床检查和架分析的结果均显示前牙牙根吸收组在侧方运动中前牙和后牙出现干扰的数量高于对照组,其中架分析发现牙根吸收患者在侧方运动中前牙出现干扰的数量显著高于对照组(P<0.05)。结论:未经治疗的错畸形患者在侧方运动过程中前牙干扰是发生前牙牙根吸收者可能原因。 展开更多
关键词 牙根吸收 [牙合] 功能
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Functional reconstruction following brachial plexus root avulsion
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作者 Guixin Sun Cunyi Fan Yudong Gu 《Neural Regeneration Research》 SCIE CAS CSCD 2007年第1期54-57,共4页
OBJECTIVE: To sum up the treatment of brachial plexus root avulsion and the progress in functional reconstruction and rehabilitation following brachial plexus root avulsion. DATA SOURCES: A search of Medline was per... OBJECTIVE: To sum up the treatment of brachial plexus root avulsion and the progress in functional reconstruction and rehabilitation following brachial plexus root avulsion. DATA SOURCES: A search of Medline was performed to select functional reconstruction and rehabilitation following brachial plexus injury-related English articles published between January 1990 and July 2006, with key words of "brachial plexus injury, reconstruction and rehabilitation". Meanwhile, a computer-based search of CBM was carried out to select the similar Chinese articles published between January 1998 and July 2006, with key words of "brachial plexus injury, reconstruction and rehabilitation". STUDY SELECTION: The materials were checked primarily, and the literatures of functional reconstruction and rehabilitation of brachial plexus injury were selected and the full texts were retrieved. Inclusive criteria: ①Functional reconstruction following brachial plexus injury. ②Rehabilitation method of brachial plexus injury. Exclusive criteria: Reviews, repetitive study, and Meta analytical papers. DATA EXTRACTION: Forty-six literatures about functional reconstruction following brachial plexus injury were collected, and 36 of them met the inclusive criteria. DATA SYNTHESIS: Brachial plexus injury causes the complete or incomplete palsy of muscle of upper extremity. The treatment of brachial plexus is to displace not very important nerves to the distal end of very important nerve, called nerve transfer, which is an important method to treat brachial plexus injury. Postoperative rehabilitations consist of sensory training and motor functional training. It is very important to keep the initiativeness of exercise. Besides recovering peripheral nerve continuity by operation, combined treatment and accelerating neural regeneration, active motors of cerebral cortex is also the important factor to reconstruct peripheral nerve function. CONCLUSION: Consciously and actively strengthening functional exercise after operation is helpful to form cerebral plasticity and produce voluntary movements, can re-educate re-dominated muscle, obviously improves postoperative therapeutic effect and promote functional reconstruction. 展开更多
关键词 brachial plexus root avulsion functional reconstruction review literature
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单尖法根管填充联合iRoot SP治疗牙体牙髓病患者的效果
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作者 王萌 赵焕芝 《中外医学研究》 2025年第30期27-31,共5页
目的:探讨单尖法根管填充联合iRoot SP治疗牙体牙髓病患者的效果。方法:以2022年5月—2024年5月于西安市高陵区医院接受治疗的86例牙体牙髓病患者作为研究对象,根据随机数表法分为观察组和对照组,各43例。对照组采用冷侧压法填充iRoot S... 目的:探讨单尖法根管填充联合iRoot SP治疗牙体牙髓病患者的效果。方法:以2022年5月—2024年5月于西安市高陵区医院接受治疗的86例牙体牙髓病患者作为研究对象,根据随机数表法分为观察组和对照组,各43例。对照组采用冷侧压法填充iRoot SP治疗,观察组采用单尖法根管填充联合iRoot SP治疗。比较两组牙龈健康状况和咀嚼功能、疼痛、炎症、填充效果和并发症发生情况。结果:术前两组牙龈健康状况、咀嚼功能、疼痛程度、炎症水平比较,差异无统计学意义(P>0.05);术后两组龈沟出血指数、牙龈指数、炎症因子水平降低,且观察组相较于对照组更低,咬合力升高,且观察组高于对照组,差异有统计学意义(P<0.05);术后1 d、7 d、14 d两组视觉模拟量表评分均降低,且观察组相较于对照组更低,差异有统计学意义(P<0.05)。观察组的恰填率高于对照组,根管充填操作时间短于对照组,差异有统计学意义(P<0.05)。观察组感染、牙龈肿胀、剧烈疼痛的总发生率低于对照组,差异有统计学意义(P<0.05)。结论:牙体牙髓病患者应用单尖法根管填充联合iRoot SP治疗,可以改善牙龈健康状况和咀嚼功能,减轻疼痛和炎症反应,根管填充效果好,安全性高。 展开更多
关键词 牙体牙髓病 单尖法根管填充 iroot SP 咀嚼功能
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沙地固定程度对红砂灌丛叶-根功能性状权衡关系的影响
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作者 杨倩 《水土保持通报》 北大核心 2026年第1期48-56,共9页
[目的]研究沙地固定程度对红砂(Reaumuria songarica)灌丛叶-根功能性状的影响,为探究干旱区植物适应策略,保护植物多样性提供更多理论依据与数据支持。[方法]选择鄂尔多斯高原不同固定程度沙地上红砂灌丛作为研究对象,采用方差分析、Pe... [目的]研究沙地固定程度对红砂(Reaumuria songarica)灌丛叶-根功能性状的影响,为探究干旱区植物适应策略,保护植物多样性提供更多理论依据与数据支持。[方法]选择鄂尔多斯高原不同固定程度沙地上红砂灌丛作为研究对象,采用方差分析、Pearson相关性等分析方法,探究叶片与根系的功能性状特征,解析其养分含量规律。[结果](1)流动沙地的植物叶片相较于固定-半固定沙地表现为低肉质化程度(2.08)、低叶含水量(51.68%)、低叶饱和含水量(57.47%)、低叶C(34.9 g/kg)和低叶N(2.32 g/kg)的保守型策略,而根系则表现为更广的根系分布范围和高根N含量的获取型策略。(2)相较于半固定沙地,流动沙地多数指标相对作用强度值(RII)更远离零值。(3)多数叶片与根系的功能性状之间存在显著相关性(p<0.05)。[结论]红砂灌丛在适应胁迫环境时表现出地上地下性状解耦现象,并且随着环境压力的增加,植物性状变化更加明显。 展开更多
关键词 植物功能性状 叶片 根系 荒漠草原过渡带
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iRoot SP单尖法在牙体牙髓疾病根管治疗中的优势及牙周状态改善效果
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作者 黄华锋 周晖 谢恩惠 《世界复合医学(中英文)》 2025年第5期89-92,共4页
目的探讨iRoot SP单尖法在牙体牙髓疾病根管治疗中优势及牙周状态改善效果。方法选取2022年6月—2023年6月惠州口腔医院收治的98例牙体牙髓病患者为研究对象,以填充材料不同分为常规糊剂组(n=49)和生物陶瓷单尖组(n=49),两组均使用根管... 目的探讨iRoot SP单尖法在牙体牙髓疾病根管治疗中优势及牙周状态改善效果。方法选取2022年6月—2023年6月惠州口腔医院收治的98例牙体牙髓病患者为研究对象,以填充材料不同分为常规糊剂组(n=49)和生物陶瓷单尖组(n=49),两组均使用根管治疗,常规糊剂组采用AHplus根充糊剂填充,生物陶瓷单尖组采用iRoot SP单尖填充。对比两组牙周状态、咀嚼功能、疼痛程度及不良反应发生情况。结果治疗后,生物陶瓷单尖组临床附着水平、菌斑指数、牙龈出血指数均低于常规糊剂组,咬合力和咀嚼效率均高于常规糊剂组,差异均有统计学意义(P均<0.05)。治疗后,与常规糊剂组相比,生物陶瓷单尖组疼痛程度持续降低,差异均有统计学意义(P均<0.05)。生物陶瓷单尖组不良反应发生率为2.04%(1/49),低于常规糊剂组的14.29%(7/49),差异有统计学意义(χ^(2)=4.900,P<0.05)。结论根管治疗中采用iRoot SP单尖法治疗可改善患者牙周状态、提高咀嚼功能。 展开更多
关键词 iroot SP单尖法 牙体牙髓疾病 根管治疗 牙周状态 咀嚼功能
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石质山地主要树种根序功能性状分异的生态适应策略
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作者 韦柳端 于淼 +5 位作者 林建 杨智慧 董天心 户佐佑 姜文珊 徐程扬 《生态学报》 北大核心 2026年第4期2024-2035,共12页
测量两组根序(1—3级根和4—5级根)的7个功能性状,分析其在不同石砾含量梯度下的变化,以探讨观赏树种在石质山地环境中,细根性状的变异及其适应策略。结果表明:(1)随着石砾含量的增加,1—3级根的比根表面积(SRA)和比根长(SRL)随石砾含... 测量两组根序(1—3级根和4—5级根)的7个功能性状,分析其在不同石砾含量梯度下的变化,以探讨观赏树种在石质山地环境中,细根性状的变异及其适应策略。结果表明:(1)随着石砾含量的增加,1—3级根的比根表面积(SRA)和比根长(SRL)随石砾含量增加显著减少,而根直径(RD)、根组织密度(RTD)和根碳含量(RCC)显著增加。4—5级根序则相反,即随石砾含量增加4—5级根的资源吸收能力增强;(2)不同根序在石砾含量梯度上表现为两个维度:PC1(占总变异的49.04%)由“协作”梯度(与RD和SRA相关)解释;PC2(占总变异的18.08%)代表了一个资源获取梯度,与RTD和根氮含量(RNC)相关,即获取-保守策略。1—3级根序主要与PC2有关,而4—5级根序在PC1上得分更高。(3)根系性状网络结构也随着石砾环境梯度也相应发生变化,土壤石砾越多性状之间的相关性和连接性越强,同时1—3级根序性状的网络结构比4—5级根序复杂;总体而言,不同根序承担的功能不同,1—3级根倾向于“自己做”的资源获取策略,而4—5级根则更倾向于与菌根真菌合作的资源保守策略。在石质环境中根序发生功能转变,观赏树种利用低级根粗化而高级根细化的特殊根系性状可能更具有优势。这些发现有助于更好地理解植物在石质土壤中的生存策略和机制,并为树木在石质山地区域的持续生存提供了理论依据。 展开更多
关键词 石质山地 根序 根系功能性状 根系经济谱 适应策略
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Trade-offs among fine-root phosphorus-acquisition strategies of 15 tropical woody species 被引量:1
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作者 Yuxin Li Lijuan Sun Biao Zhu 《Forest Ecosystems》 SCIE CSCD 2022年第4期577-583,共7页
Aims: Plant roots show various functional strategies in soil phosphorus(P) acquisition. Under limited soil phosphatase activity, P deficiency is the main concern, and roots either invest carbon(C) to produce higher le... Aims: Plant roots show various functional strategies in soil phosphorus(P) acquisition. Under limited soil phosphatase activity, P deficiency is the main concern, and roots either invest carbon(C) to produce higher levels of phosphatase or establish more symbioses with mycorrhizal fungi. However, these strategies and their interactions are not clear. Furthermore, few studies have investigated trade-offs of functional traits in woody species associated with different types of mycorrhizal partners.Methods: Here we examined the abilities to release acid phosphatase(AP) and the colonization ratio by arbuscular and ectomycorrhizal fungi for fine roots of 15 woody species growing in a tropical common garden in Xishuangbanna, China. We also measured acid phosphatase activities of bulk soils under the canopy of target trees.Results: Soil and root AP activities exhibited a positive correlation, indicating that roots actively produced AP to acquire P even bulk soil AP was increasing. We found a significantly negative correlation(P=0.02) between mycorrhizal colonization ratio and root-released AP activity across target species, reflecting a trade-off between these two P acquisition strategies.Conclusions: Our findings suggest a trade-off of resource allocation between these two strategies at both species and individual levels, and provide information on the overall mechanism of P acquisition by fine roots that they either ‘do it by themselves’ or ‘rely on mycorrhizal partners’. These two strategies might be integrated into the collaboration gradient of the root economics space. 展开更多
关键词 root functional traits Phosphorus acquisition Mycorrhizal fungi Colonization ratio Acid phosphatase
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血清铁死亡相关特定指标与阿尔茨海默病的相关性
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作者 谢伊代·阿卜迪米吉提 宋向新 +1 位作者 迪丽热巴·艾则孜 哈斯也提·依不来音 《实用医学杂志》 北大核心 2026年第1期94-100,共7页
目的 研究阿尔茨海默病(AD)患者血清中铁死亡相关谷胱甘肽(GSH)、谷胱甘肽过氧化酶4(GPX4)、同型半胱氨酸(Hcy)、血清铁水平的变化,分析其与认知功能的相关性;评价血清铁死亡相关指标对AD的诊断价值。方法 选取就诊于新疆医科大学第二... 目的 研究阿尔茨海默病(AD)患者血清中铁死亡相关谷胱甘肽(GSH)、谷胱甘肽过氧化酶4(GPX4)、同型半胱氨酸(Hcy)、血清铁水平的变化,分析其与认知功能的相关性;评价血清铁死亡相关指标对AD的诊断价值。方法 选取就诊于新疆医科大学第二附属医院住院的AD患者37例,同期住院无认知障碍人群35例。对所有受试者进行神经心理学评估,并检测血清GSH、GPX4、Hcy、血清铁的水平。比较两组的一般资料,分析GSH、GPX4、Hcy、血清铁与简易精神状态检查量表(MMSE)、蒙特利尔认知评估量表(MoCA)评分的相关性,采用单因素和多因素二元logistic回归分析探讨AD的影响因素,构建其预测模型,绘制受试者工作特征(ROC)曲线评价预测模型对AD的诊断价值。结果 (1)与对照组比较,AD组的血清GSH水平(23.573±8.862)μmol/L和GPX4水平(21.767±9.609)μU/mL均显著降低(P<0.05),对照组血清GSH、GPX4的相应水平分别为(34.380±19.673)μmol/L和(31.345±10.553)μU/mL。两组血清铁及Hcy水平比较,差异无统计学意义(P>0.05)。(2)血清中GPX4与MMSE评分(r=0.233,P=0.049)、MoCA评分(r=0.296,P=0.011)呈正相关,血清铁与MoCA评分(r=0.252,P=0.033)呈正相关。(3)多因素二元logitic回归分析示BMI(OR=0.794,P<0.05)和血清GPX4(OR=0.917,P<0.05)是AD发生的保护因素。血清GPX4水平诊断AD的曲线下面积(AUC)为0.766(95%CI:0.656~0.877),灵敏度为67.6%,特异度为77.1%,截断值(cut-off)为44.7(P<0.05);联合BMI和GPX4水平诊断AD的AUC值为0.815(95%CI:0.715~0.914),灵敏度为81.1%,特异度为77.1%(P<0.05)。结论 (1)AD患者血清GSH和GPX4水平降低。(2)血清GPX4和血清铁水平与其认知功能呈正相关。(3)BMI和血清GPX4是AD的影响因素,且其与联合因素构建的预测模型对AD具有一定的预测价值。 展开更多
关键词 阿尔茨海默病 铁死亡相关指标 认知功能 影响因素分析
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不同类型促根肥料对番茄生长的影响
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作者 崔腾飞 曹新蕊 +7 位作者 王永成 车辂 肖长坤 王金茹 戴宇婷 郝晓建 聂青 杨明宇 《中国果菜》 2026年第1期69-73,94,共6页
为探索不同类型促进根系生长的功能性肥料(矿源黄腐酸钾、微生物菌肥、肌醇)对口感型番茄长势、品质、产量等相关指标的影响,于每穗果坐果后,在常规追施大量元素水溶肥(T1)的基础上分别施加上述几种肥料,通过测定番茄植株和根系长势,以... 为探索不同类型促进根系生长的功能性肥料(矿源黄腐酸钾、微生物菌肥、肌醇)对口感型番茄长势、品质、产量等相关指标的影响,于每穗果坐果后,在常规追施大量元素水溶肥(T1)的基础上分别施加上述几种肥料,通过测定番茄植株和根系长势,以及可溶性固形物、可溶性糖、维生素C含量等品质指标。结果表明,3种肥料中肌醇对番茄植株长势促进作用最为明显,株高、茎粗分别较T1增长了15.05%和7.00%;产量为6935.04 kg/667 m^(2),在各处理中最优,较T1增长了14.22%;可溶性糖、维生素C含量等均高于其他各处理。综合番茄田间长势、品质、产量等指标,三种肥料中肌醇对番茄长势、品质及产量的效果最优,可以作为生产中促进越冬茬口番茄根系生长的功能性肥料推广应用。 展开更多
关键词 根系生长 功能性肥料 番茄 长势 品质 产量
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聚合瓷高嵌体对根管治疗后的下颌第二前磨牙咀嚼功能及牙龈状况的影响
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作者 孙培培 毛甜甜 +1 位作者 张明伟 黄志强 《口腔颌面修复学杂志》 2026年第1期23-30,共8页
目的:探讨聚合瓷高嵌体对根管治疗后的下颌第二前磨牙咀嚼功能及牙龈状况的影响。方法:前瞻性选择2020年1月至2023年1月于武汉大学口腔医院进行根管治疗后的116例下颌第二前磨牙牙体缺损患者为研究对象,根据治疗方式不同,分层随机分为... 目的:探讨聚合瓷高嵌体对根管治疗后的下颌第二前磨牙咀嚼功能及牙龈状况的影响。方法:前瞻性选择2020年1月至2023年1月于武汉大学口腔医院进行根管治疗后的116例下颌第二前磨牙牙体缺损患者为研究对象,根据治疗方式不同,分层随机分为治疗组(n=58)和对照组(n=58),治疗组采用Ceramage聚合瓷高嵌体治疗,对照组采用树脂填充治疗,比较两组患者的一般资料及治疗前后的咀嚼功能、牙龈状况、修复成功率及临床疗效。采用广义估计方程(GEE)模型分析两组患者治疗前后咀嚼功能与牙龈状况。结果:治疗后,与对照组相比,治疗组咀嚼效率具有显著统计学差异(P<0.05);与同组治疗前相比,两组患者咀嚼效率显著增加(P<0.05);两组咀嚼效率均较同组治疗前存在上升趋势,且治疗组差异显著(P<0.05)。治疗后,两组患者菌斑指数、牙龈指数均较治疗前显著降低(P<0.05);治疗组菌斑指数、牙龈指数均明显低于对照组(P<0.05);治疗组修复成功率、邻接关系、边缘密合、修复体完整性、牙龈健康方面均明显优于对照组(P<0.05);分层交互检验结果显示,校正其他因素后,咀嚼效率与菌斑指数、牙龈指数的关系依然存在(P<0.05)。进一步经过交互检验(P_(交互))后,发现校正因素不影响咀嚼效率与菌斑指数、牙龈指数之间的关系(P_(交互)<0.05);GEE模型分析结果显示,治疗组选用的治疗方式对咀嚼功能与牙龈状况的影响均有统计学意义(P<0.05)。结论:采用Ceramage聚合瓷高嵌体修复根管治疗后的下颌第二前磨牙牙体缺损,可有效提升患者的咀嚼功能,改善牙龈状况,具有临床应用价值。 展开更多
关键词 聚合瓷 根管治疗 咀嚼功能 牙龈状况
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基于SIMD的Square Root函数高性能实现与优化 被引量:2
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作者 赵永浩 贾海鹏 +1 位作者 张云泉 张思佳 《计算机工程与科学》 CSCD 北大核心 2021年第4期662-669,共8页
在计算机图形学、积分计算和神经网络等应用场景中,平方根函数的高性能实现在构建处理器的基础软件生态中起到了十分重要的作用。随着ARM架构处理器得到广泛的使用,研究ARM架构下的函数快速算法实现变得更加关键。当前大量处理器都采用... 在计算机图形学、积分计算和神经网络等应用场景中,平方根函数的高性能实现在构建处理器的基础软件生态中起到了十分重要的作用。随着ARM架构处理器得到广泛的使用,研究ARM架构下的函数快速算法实现变得更加关键。当前大量处理器都采用了SIMD架构,所以,研究基于SIMD实现高性能函数计算方法具有重要的研究意义和发展前景。因此,对平方根函数进行了高性能的实现与优化。通过分析IEEE 754标准的浮点数在内存中的存储格式,设计了高效的平方根函数算法;然后通过结合平方根倒数和泰勒公式算法,进一步提高了算法精度;最后通过SIMD优化进一步提升了算法性能。实验结果表明,在满足精度的前提下,相比于libm算法库,实现的平方根函数的,性能提高了约7倍,相比于ARM V8提供的计算平方根的指令在性能上提高了约3倍。 展开更多
关键词 平方根函数 SIMD 高性能 数值分析 ARM V8架构
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重复经颅磁刺激在脑卒中患者上肢运动康复中的应用效果及其影响因素
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作者 李翠 古剑雄 《实用心脑肺血管病杂志》 2026年第4期25-30,共6页
脑卒中后遗留的上肢运动功能障碍会严重影响患者的生活质量,重复经颅磁刺激(rTMS)作为一种无创的神经调控技术,在脑卒中患者上肢运动康复领域备受关注。本文详细阐述了rTMS在脑卒中患者上肢运动康复中的应用效果及其影响因素,指出不同... 脑卒中后遗留的上肢运动功能障碍会严重影响患者的生活质量,重复经颅磁刺激(rTMS)作为一种无创的神经调控技术,在脑卒中患者上肢运动康复领域备受关注。本文详细阐述了rTMS在脑卒中患者上肢运动康复中的应用效果及其影响因素,指出不同模式的rTMS均能促进脑卒中患者上肢运动功能康复,且可能≥10 Hz的高频重复经颅磁刺激(HF-rTMS)的治疗效果更好,此外,rTMS治疗效果也受刺激频率、刺激强度、序列参数、靶点选择与定位的准确性的影响。 展开更多
关键词 卒中 经颅磁刺激 上肢运动功能 康复 影响因素分析
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Effects of clump spacing on nutrient distribution and root activity of Dendrocalamus strictus in the humid region of Kerala,peninsular India 被引量:1
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作者 B. H. Kittur K. Sudhakara +2 位作者 B. Mohan Kumar T. K. Kunhamu P. Sureshkumar 《Journal of Forestry Research》 SCIE CAS CSCD 2017年第6期1133-1144,共12页
The humid agroclimatic conditions of Kerala,India permit the cultivation of an array of bamboo species of which Dendrocalamus strictus Roxb.(Nees.) is an important one on account of its high growth rate and multiple u... The humid agroclimatic conditions of Kerala,India permit the cultivation of an array of bamboo species of which Dendrocalamus strictus Roxb.(Nees.) is an important one on account of its high growth rate and multiple uses. Stand density, a potential tool in controlling the productivity of woody ecosystems, its effect on growth and root distribution patterns may provide a better understanding of productivity optimization especially when bamboo-based intercropping options are considered.Growth attributes of 7-year-old bamboo(D. strictus) stands managed at variable spacing(4×4 m, 6×6 m, 8×8 m,10×10 m, 12×12 m) were studied. Functional root activity among bamboo clumps were also studied using a radio tracer soil injection method in which the radio isotopeP was applied to soil at varying depths and lateral distances from the clump. Results indicate that spacing exerts a profound influence on growth of bamboo. Widely spaced bamboo exhibited higher clump diameters and crown widths while clump heights were better under closer spacing. Clump height was 30% lower and DBH 52%higher at the widest spacing(12×12 m) compared to the closest spacing(4×4 m). With increasing soil depth and lateral distance, root activity decreased significantly. Root activity near the clump base was highest(809 counts per minute, cpm; 50 cm depth and 50 cm lateral distance) at 4×4 m. Tracer study further showed wider distribution of root activity with increase in clump spacing. It may be concluded that the intensive foraging zone of bamboo is within a 50-cm radius around the clump irrespective of spacing. N, P and K content in the upper 20 cm was 2197,21, and 203 kg/ha respectively for the closely spaced bamboo(4×4 m) which were significantly higher than corresponding nutrient content at wider spacings. About 50% of N, P and K were present within the 0–20 cm soil layer, which decreased drastically beyond the 20 cm depth.The results suggest that stand management practices through planting density regulation can modify the resource acquisition patterns of D. strictus which in turn can change growth and productivity considerably. Such information on root activities, spatial and temporal strategies of resource sharing will be helpful in deciding the effective nutrition zone for D. strictus. Further, the study throws light on the spatial distribution of non-competitive zones for productivity optimization yields, especially when intercropping practices are considered. 展开更多
关键词 BAMBOO Clump spacing functional root activity Radio tracer 32P Soil nutrients
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百年来农村基层党组织的功能演变:发展历程与动力构成——基于结构功能主义的分析视角
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作者 康儿丽 《山西农业大学学报(社会科学版)》 2026年第1期107-118,共12页
基于结构功能主义的理论分析视角,将农村基层党组织的功能输出与农村社会系统整体结构进行勾连,通过对百年来农村基层党组织的功能演变历程勾勒,探究农村基层党组织功能变迁的动力。研究发现:农村基层党组织功能受到农村社会系统内部各... 基于结构功能主义的理论分析视角,将农村基层党组织的功能输出与农村社会系统整体结构进行勾连,通过对百年来农村基层党组织的功能演变历程勾勒,探究农村基层党组织功能变迁的动力。研究发现:农村基层党组织功能受到农村社会系统内部各要素间结构状态的影响,先后经历从组织动员、社会统合、枢纽互动、引领协调向统筹领导的演变。宏观制度环境的嬗变与社会生产力的发展推动了农村社会系统内部治理主体的多元化,并改变了农村社会系统内部治理主体间的结构状态。在此过程中,农村基层党组织受到自我革新的环境适应性动力、落实党和国家农村工作任务的目标达成性动力、聚合与领导农村治理力量的主体整合性动力、维护与实现人民利益诉求的理念维持性动力影响,主动进行系统结构位置的调整,进而转变其组织功能,推动系统内部结构状态的有序化,为农业农村的现代化提供坚实保障。 展开更多
关键词 农村基层党组织 农村社会系统 功能演变 动力构成
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