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Effect of Particle Number Density on Wave Dispersion in a Two-Dimensional Yukawa System
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作者 张壤月 刘艳红 +2 位作者 黄峰 陈朝阳 李春燕 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第7期155-159,共5页
Effect of the particle number density on the dispersion properties of longitudinal and transverse lattice waves in a two-dimensional Yukawa charged-dust system is investigated using molecular dynamics simulation. The ... Effect of the particle number density on the dispersion properties of longitudinal and transverse lattice waves in a two-dimensional Yukawa charged-dust system is investigated using molecular dynamics simulation. The dispersion relations for the waves are obtained. It is found that the frequencies of both the longitudinal and transverse dust waves increase with the density and when the density is sufficiently high a cutoff region appears at the short wavelength. With the increase of the particle number density, the common frequency tends to increase, and the sound speed of the longitudinal wave also increases, but that of the transverse wave remains low. 展开更多
关键词 Effect of Particle number Density on Wave Dispersion in a two-dimensional Yukawa System
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Effect of the number of positive lymph nodes and lymph node ratio on prognosis of patients after resection of pancreatic adenocarcinoma 被引量:6
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作者 Zu-Qiang Liu Zhi-Wen Xiao +6 位作者 Guo-Pei Luo Liang Liu Chen Liu Jin Xu Jiang Long Quan-Xing Ni Xian-Jun Yu 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2014年第6期634-641,共8页
BACKGROUND: The prognostic factors related to lymph node involvement [lymph node status, the number of positive lymph nodes, lymph node ratio (LNR)] and the number of nodes evaluated in patients with pancreatic ade... BACKGROUND: The prognostic factors related to lymph node involvement [lymph node status, the number of positive lymph nodes, lymph node ratio (LNR)] and the number of nodes evaluated in patients with pancreatic adenocarcinoma after pancreatectomy are poorly defined. METHODS: A total of 167 patients who had undergone resection of pancreatic adenocarcinoma from February 2010 to August 2011 were included in this study. Histological examination was performed to evaluate the tumor differentiation and lymph node involvement. Univariate and multivariate analyses were made to determine the relationship between the variables related to nodal involvement and the number of nodes and survival. RESULTS: The median number of total nodes examined was 10 (range 0-44) for the entire cohort. The median number of total nodes examined in node-negative (pN0) patients was similar to that in node-positive (pN1) patients. Patients with pN1 diseases had significantly worse survival than those with pN0 ones (P=0.000). Patients with three or more positive nodes had a poorer prognosis compared with those with the negative nodes (P=0.000). The prognosis of the patients with negative nodes was similar to that of those with one to two positive nodes (P=0.114). The median survival of patients with an LNR ≥0.4 was shorter than that of patients with an LNR 〈0.4 in the pN1 cohort (P=0.014). No significance was found between the number of total nodes examined and the prognosis, regardless of the cutoff of 10 or 12 and in the entire cohort or the pN0 and pN1 groups. Based on the multivariate analysis of the entire cohort and the pN1 group, the nodal status, the number of positive nodes and the LNR were all associated with survival. CONCLUSIONS: In addition to the nodal status, the number of positive nodes and the LNR can serve as comprehensive factors for the evaluation of nodal involvement. This approach may be more effective for predicting the survival of patients with pancreatic adenocarcinoma after pancreatectomy. 展开更多
关键词 lymph node status lymph node ratio number of positive nodes number of total nodes examined pancreatic adenocarcinoma PANCREATECTOMY
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Relationship between celiac artery variation and number of lymph nodes dissection in gastric cancer surgery 被引量:4
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作者 Guang-Chuan Mu Yuan Huang +4 位作者 Zhi-Ming Liu Zhi-Bai Chen Xiang-Hua Wu Xin-Gan Qin Yan-Jun Zeng 《World Journal of Gastrointestinal Oncology》 SCIE CAS 2019年第6期499-508,共10页
BACKGROUND Radical D2 lymphadenectomy for advanced gastric cancer as a standard procedure has gained global consensus. Mounting studies have shown that the number of lymph nodes dissection directly affects the prognos... BACKGROUND Radical D2 lymphadenectomy for advanced gastric cancer as a standard procedure has gained global consensus. Mounting studies have shown that the number of lymph nodes dissection directly affects the prognosis and recurrence of gastric cancer. Our previous study showed that there was no obvious lymph node around the abnormal hepatic artery derived from the superior mesenteric artery. AIM To investigate the relationship between celiac artery variation and the number of lymph nodes dissection in gastric cancer surgery. METHODS The clinicopathological data of 421 patients treated with radical D2 lymphadenectomy were analyzed retrospectively. The difference of the number of lymph nodes dissection between the celiac artery variation group and the normal vessels group and the relationship with prognosis were analyzed. RESULTS Celiac artery variation was found in 110 patients, with a variation rate of 26.13%. Celiac artery variation, tumor staging, and Borrmann typing were factors that affected lymph node clearance in gastric cancer, and the number of lymph nodes dissection in patients with celiac artery variation was significantly less than that of non-variant groups (P < 0.05). Univariate analysis showed that there was no significant difference in survival time between the two groups (P > 0.05). Univariate and multiple Cox regression analysis showed that celiac artery variation was not a prognostic factor for gastric cancer (P > 0.05). Tumor staging, intraoperative bleeding, and positive lymph node ratio were prognostic factors for gastric cancer patients (all P < 0.05). CONCLUSION The number of lymph nodes dissection in patients with celiac artery variation was reduced, but there was no obvious effect on prognosis. Therefore, lymph nodes around the abnormal hepatic artery may not need to be dissected in radical D2 lymphadenectomy. 展开更多
关键词 Gastric cancer CELIAC artery VARIATION LYMPHADENECTOMY number of LYMPH nodes Prognosis
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Elevated temperature intensity,timing,and duration of exposure affect soybean internode elongation,mainstem node number,and pod number per plant 被引量:3
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作者 Leon Hartwell Allen Jr. Lingxiao Zhang +1 位作者 Kenneth J.Boote Bernard A.Hauser 《The Crop Journal》 SCIE CAS CSCD 2018年第2期148-161,共14页
A study was conducted in four compartments of a polycarbonate greenhouse at Gainesville,FL, USA to investigate how a soybean(Glycine max L. Merr.) cultivar, Maverick(maturity group III, indeterminate), responded to th... A study was conducted in four compartments of a polycarbonate greenhouse at Gainesville,FL, USA to investigate how a soybean(Glycine max L. Merr.) cultivar, Maverick(maturity group III, indeterminate), responded to three elevated temperatures, ELT,(day/night of 34/26 °C, 38/30 °C, and 42/34 °C) in comparison to a control growth temperature(30/22 °C).Carbon dioxide(CO_2) concentration was maintained at 700 μmol mol^(-1) in each compartment by a processor controlled air-sampling and CO_2-injection system. Three sequential experiments were conducted at different times of year(summer, autumn, and early spring)to investigate the effect of intensity, timing, and duration of ELT on soybean node number,internode elongation, mainstem length, and number of pods set per plant. At the control temperature, the soybean plants grown in the polycarbonate greenhouse were taller than field-grown plants. When plants were grown under continuous ELT applied soon after sowing or at initial flowering, the number of nodes increased with increasing ELT intensity,whereas the length of individual internodes decreased. When ELT treatment was applied during the beginning of flowering stage(R1–R2) or earlier, more nodes were produced and the length of affected internodes was decreased. When the ELT was imposed later at reproductive stage R5+ just before the beginning of seed filling, effects on node numbers and internode lengths were negligible. Short-term(10-day) duration of ELT applied at four stages from V3 to R5+ did not significantly affect final mean numbers of nodes or mean mainstem lengths. Possible mechanisms of elevated temperature effects on soybean internode elongation and node number(internode number) are discussed. Total pod numbers per plant increased linearly with mainstem node numbers and mainstem length.Furthermore, total pod numbers per plant were greatest at 34/26 °C rather than at the control temperature of 30/22 °C(and remained high at 38/30 °C). Mild increases in temperature might not threaten, but actually increase, yields of soybean in northerly zones where this crop is currently grown at slightly suboptimal temperatures. However, a sustained increase in ambient temperature would likely threaten soybean yields. 展开更多
关键词 Elevated temperature INTERnode ELONGATION node number POD yield SOYBEAN PHENOLOGY
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The number of tumor-free axillary lymph nodes removed as a prognostic parameter for node-negative breast cancer 被引量:1
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作者 Fei Gao Ni He Pei-Hong Wu 《Chinese Journal of Cancer》 SCIE CAS CSCD 2014年第11期569-573,共5页
Recently, there has been controversy about the relationship between the number of lymph nodes removed and survival of patients diagnosed with lymph node-negative breast cancer. To assess this relationship, 603 cases o... Recently, there has been controversy about the relationship between the number of lymph nodes removed and survival of patients diagnosed with lymph node-negative breast cancer. To assess this relationship, 603 cases of lymph node-negative breast cancer with a median of 126 months of follow-up data were studied. Patients were stratified into two groups(Group A, 10 or fewer tumor-free lymph nodes removed; Group B, more than 10 tumor-free lymph nodes removed). The number of tumor-free lymph nodes in ipsilateral axillary resections as well as 5 other disease parameters were analyzed for prognostic value. Our results revealed that the risk of death from breast cancer was significantly associated with patient age, marital status, histologic grade, tumor size, and adjuvant therapy. The 5- and 10-year survival rates for patients with 10 or fewer tumor-free lymph nodes removed was 88.0% and 66.4%, respectively, compared with 69.2% and 51.1%, respectively, for patients with more than 10 tumor-free lymph nodes removed. For patients with 10 or fewer tumor-free lymph nodes removed, the adjusted hazard ratio(HR) for risk of death from breast cancer was 0.579(95% confidence interval, 0.492-0.687, P < 0.001), independent of patient age, marital status, histologic grade, tumor size, and adjuvant therapy. Our study suggests that the number of tumor-free lymph nodes removed is an independent predictor in cases of lymph node-negative breast cancer. 展开更多
关键词 number tumor-free axillary lymph nodes prognostic parameter lymph node-negative breast cancer
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Metastatic lymph nodes and prognosis assessed by the number of retrieved lymph nodes in gastric cancer
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作者 Hao Wang Xin Yin +12 位作者 Sheng-Han Lou Tian-Yi Fang Bang-Ling Han Jia-Liang Gao Yu-Fei Wang Dao-Xu Zhang Xi-Bo Wang Zhan-Fei Lu Jun-Peng Wu Jia-Qi Zhang Yi-Min Wang Yao Zhang Ying-Wei Xue 《World Journal of Gastrointestinal Surgery》 SCIE 2022年第11期1230-1249,共20页
BACKGROUND The prognostic value of quantitative assessments of the number of retrieved lymph nodes(RLNs)in gastric cancer(GC)patients needs further study.AIM To discuss how to obtain a more accurate count of metastati... BACKGROUND The prognostic value of quantitative assessments of the number of retrieved lymph nodes(RLNs)in gastric cancer(GC)patients needs further study.AIM To discuss how to obtain a more accurate count of metastatic lymph nodes(MLNs)based on RLNs in different pT stages and then to evaluate patient prognosis.METHODS This study retrospectively analyzed patients who underwent GC radical surgery and D2/D2+LN dissection at the Cancer Hospital of Harbin Medical University from January 2011 to May 2017.Locally weighted smoothing was used to analyze the relationship between RLNs and the number of MLNs.Restricted cubic splines were used to analyze the relationship between RLNs and hazard ratios(HRs),and X-tile was used to determine the optimal cutoff value for RLNs.Patient survival was analyzed with the Kaplan-Meier method and log-rank test.Finally,HRs and 95%confidence intervals were calculated using Cox proportional hazards models to analyze independent risk factors associated with patient outcomes.RESULTS A total of 4968 patients were included in the training cohort,and 11154 patients were included in the validation cohort.The smooth curve showed that the number of MLNs increased with an increasing number of RLNs,and a nonlinear relationship between RLNs and HRs was observed.X-tile analysis showed that the optimal number of RLNs for pT1-pT4 stage GC patients was 26,31,39,and 45,respectively.A greater number of RLNs can reduce the risk of death in patients with pT1,pT2,and pT4 stage cancers but may not reduce the risk of death in patients with pT3 stage cancer.Multivariate analysis showed that RLNs were an independent risk factor associated with the prognosis of patients with pT1-pT4 stage cancer(P=0.044,P=0.037,P=0.003,P<0.001).CONCLUSION A greater number of RLNs may not benefit the survival of patients with pT3 stage disease but can benefit the survival of patients with pT1,pT2,and pT4 stage disease.For the pT1,pT2,and pT4 stages,it is recommended to retrieve 26,31 and 45 LNs,respectively. 展开更多
关键词 Gastric cancer Metastatic lymph nodes number of retrieved lymph nodes PROGNOSIS
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Prognostic significance of the number of pelvic lymph nodes removed in patients with early cervical cancer
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作者 Jing Zhao Weihong Dong 《Oncology and Translational Medicine》 2018年第2期58-61,共4页
Objective The aim of this research was to study the prognostic significance of the number of pelvic lymph nodes removed in patients with early cervical cancer.Methods We searched the Pub Med database using the terms &... Objective The aim of this research was to study the prognostic significance of the number of pelvic lymph nodes removed in patients with early cervical cancer.Methods We searched the Pub Med database using the terms "cervical cancer" and "lymph nodes" or "lymphadenectomy". Studies on the association between number of lymph nodes removed and prognosis or survival were identified. We retrospectively studied the relevant research.Results Ten retrospective studies were included. Two studies indicated that the number of lymph nodes had no association with prognosis whereas three studies found a positive relationship. Five studies indicated some factors that could influence the relationship between number of lymph nodes and prognosis.Conclusion The number of lymph nodes removed may positively influence the prognosis of patients with cervical cancer. Some factors may influence the relationship between the extent of lymph nodes removed and patient prognosis. Additional multicenter, prospective studies with large samples are required to confirm the study findings. 展开更多
关键词 cervical cancer PROGNOSIS number of lymph nodes pelvic lymphadenectomy
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High Precision Numerical Method for 2D Time-Fractional Diffusion-Wave Equation Using Fewer Nodes
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作者 Xindong ZHANG Nan LIN Leilei WEI 《Journal of Mathematical Research with Applications》 2025年第4期537-554,共18页
This paper focuses on applying the barycentric Lagrange interpolation collocation method(BLICM)for solving 2D time-fractional diffusion-wave equation(TFDWE).In order to obtain the discrete format of the equation,we co... This paper focuses on applying the barycentric Lagrange interpolation collocation method(BLICM)for solving 2D time-fractional diffusion-wave equation(TFDWE).In order to obtain the discrete format of the equation,we construct the multivariate barycentric Lagrange interpolation approximation function and process the integral terms by using the Gauss-Legendre quadrature formula.We provide a detailed error analysis of the discrete format on the second kind of Chebyshev nodes.The efficacy of the proposed method is substantiated by some numerical experiments.The results of these experiments demonstrate that our method can obtain high-precision numerical solutions for fractional partial differential equations.Additionally,the method's capability to achieve high precision with a reduced number of nodes is confirmed. 展开更多
关键词 two-dimensional fractional diffusion-wave equation barycentric Lagrange interpolation Caputo-Fabrizio derivative Gauss-Legendre quadrature formula Chebyshev node
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A Valuable and Low-Budget Process Scheme of Equivalized 1 nm Technology Node Based on 2D Materials
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作者 Yang Shen Zhejia Zhang +6 位作者 Zhujun Yao Mengge Jin Jintian Gao Yuhan Zhao Wenzhong Bao Yabin Sun He Tian 《Nano-Micro Letters》 2025年第8期294-305,共12页
Emerging two-dimensional(2D)semiconductors are among the most promising materials for ultra-scaled transistors due to their intrinsic atomic-level thickness.As the stacking process advances,the complexity and cost of ... Emerging two-dimensional(2D)semiconductors are among the most promising materials for ultra-scaled transistors due to their intrinsic atomic-level thickness.As the stacking process advances,the complexity and cost of nanosheet field-effect transistors(NSFETs)and complementary FET(CFET)continue to rise.The 1 nm technology node is going to be based on Si-CFET process according to international roadmap for devices and systems(IRDS)(2022,https://irds.ieee.org/),but not publicly confirmed,indicating that more possibilities still exist.The miniaturization advantage of 2D semiconductors motivates us to explore their potential for reducing process costs while matching the performance of next-generation nodes in terms of area,power consumption and speed.In this study,a comprehensive framework is built.A set of MoS2 NSFETs were designed and fabricated to extract the key parameters and performances.And then for benchmarking,the sizes of 2D-NSFET are scaled to a extent that both of the Si-CFET and 2D-NSFET have the same average device footprint.Under these conditions,the frequency of ultra-scaled 2D-NSFET is found to improve by 36%at a fixed power consumption.This work verifies the feasibility of replacing silicon-based CFETs of 1 nm node with 2D-NSFETs and proposes a 2D technology solution for 1 nm nodes,i.e.,“2D eq 1 nm”nodes.At the same time,thanks to the lower characteristic length of 2D semiconductors,the miniaturized 2D-NSFET achieves a 28%frequency increase at a fixed power consumption.Further,developing a standard cell library,these devices obtain a similar trend in 16-bit RISC-V CPUs.This work quantifies and highlights the advantages of 2D semiconductors in advanced nodes,offering new possibilities for the application of 2D semiconductors in high-speed and low-power integrated circuits. 展开更多
关键词 two-dimensional semiconductors 1 nm technology node Nanosheet field-effect transistors Complementary field-effect transistors Horizontal scaling
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Novel high-performance element in the electromagnetic finite-element method——node-edge element 被引量:1
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作者 Sheng Xinqing Peng Zhen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第5期878-881,共4页
It is known in the computational electromagnetics (CEM) that the node element has a relative wellconditioned matrix, but suffers from the spurious solution problem; whereas the edge element has no spurious solutions... It is known in the computational electromagnetics (CEM) that the node element has a relative wellconditioned matrix, but suffers from the spurious solution problem; whereas the edge element has no spurious solutions, but usually produces an ill-conditioned matrix. Particularly, when the mesh is over dense, the iterative solution of the matrix equation from edge element converges very slowly. Based on the node element and edge element, a node-edge element is presented, which has no spurious solutions and better-conditioned matrix. Numerical experiments demonstrate that the proposed node-edge element is more efficient than now-widely used edge element. 展开更多
关键词 node-edge element node element edge element matrix condition number.
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Enumeration of Protected Nodes in Motzkin Trees 被引量:1
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作者 Lin YANG Shengliang YANG 《Journal of Mathematical Research with Applications》 CSCD 2021年第2期127-140,共14页
In this paper,we enumerate the set of Motzkin trees with n edges according to the number of leaves,the number of vertices adjacent to a leaf,the number of protected nodes,the number of(protected)branch nodes,and the n... In this paper,we enumerate the set of Motzkin trees with n edges according to the number of leaves,the number of vertices adjacent to a leaf,the number of protected nodes,the number of(protected)branch nodes,and the number of(protected)lonely nodes.Explicit formulae as well as generating functions are obtained.We also find that,as n goes to infinity,the proportion of protected branch nodes and protected lonely nodes among all vertices of Motzkin trees with n edges approaches 4/27 and 2/9. 展开更多
关键词 Motzkin trees protected nodes Motzkin number Bivariate generating function Lagrange inversion
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Non-surgical factors influencing lymph node yield in colon cancer
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作者 Patrick Wood Colin Peirce Jurgen Mulsow 《World Journal of Gastrointestinal Oncology》 SCIE CAS 2016年第5期466-473,共8页
There are numerous factors which can affect the lymph node(LN) yield in colon cancer specimens.The aim of this paper was to identify both modifiable and nonmodifiable factors that have been demonstrated toaffect colon... There are numerous factors which can affect the lymph node(LN) yield in colon cancer specimens.The aim of this paper was to identify both modifiable and nonmodifiable factors that have been demonstrated toaffect colonic resection specimen LN yield and to summarise the pertinent literature on these topics.A literature review of Pub Med was performed to identify the potential factors which may influence the LN yield in colon cancer resection specimens.The terms used for the search were:LN,lymphadenectomy,LN yield,LN harvest,LN number,colon cancer and colorectal cancer.Both nonmodifiable and modifiable factors were identified.The review identified fifteen non-surgical factors:(13 nonmodifiable,2 modifiable) which may influence LN yield.LN yield is frequently reduced in older,obese patients and those with male sex and increased in patients with right sided,large,and poorly differentiated tumours.Patient ethnicity and lower socioeconomic class may negatively influence LN yield.Pre-operative tumour tattooing appears to increase LN yield.There are many factors that potentially influence the LN yield,although the strength of the association between the two varies greatly.Perfecting oncological resection and pathological analysis remain the cornerstones to achieving good quality and quantity LN yields in patients with colon cancer. 展开更多
关键词 LYMPH node number FACTORS Yield COLON cancer
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Does lymph node dissection improve the prognosis of patients with colorectal cancer?
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作者 Liang Wang Shan-Shan Liu 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第12期3895-3898,共4页
The number of lymph nodes(LNs)dissected during surgery has become an interesting topic.Simple intuition always leads us to believe that dissecting more LNs will result in more accurate pathological staging and assuran... The number of lymph nodes(LNs)dissected during surgery has become an interesting topic.Simple intuition always leads us to believe that dissecting more LNs will result in more accurate pathological staging and assurance of surgical quality.However,when the number of LNs dissected reaches a certain threshold,the patient’s prognosis does not continue to improve as the number of dissected nodes increases.Instead,an increase in the number of dissected LNs may be accompanied by a higher incidence of complications.Currently,there are only less than 40%of colorectal cancer patients undergoing adequate LN evaluation.Therefore,obtaining a sufficient number of LNs in clinical practice is extremely challenging.How to further address the insufficiency of LN dissection due to various reasons,which results in concerns of surgeons about patient prognosis,is currently a critical focus. 展开更多
关键词 number of lymph nodes Colorectal cancer Overall survival Tumor node metastasis T stage
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大豆株高和主茎节数QTL定位及候选基因挖掘 被引量:1
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作者 陈亮宇 张君 +5 位作者 韩笑 李雪莹 姚丹 宋阳 宋百兴 杨松楠 《吉林农业大学学报》 北大核心 2025年第2期226-235,共10页
株高和主茎节数是影响大豆产量的重要性状,开发相关分子标记及挖掘其分子机制有益于加速其在育种工作中的利用。以“吉农45”“绥农76”为亲本杂交得到F_(2)群体,基于对群体SNP标记构建的遗传图谱及表型数据,联合采用CIM、ICIM及GCIM 3... 株高和主茎节数是影响大豆产量的重要性状,开发相关分子标记及挖掘其分子机制有益于加速其在育种工作中的利用。以“吉农45”“绥农76”为亲本杂交得到F_(2)群体,基于对群体SNP标记构建的遗传图谱及表型数据,联合采用CIM、ICIM及GCIM 3种定位方法进行数量性状基因座(QTL)定位,并对QTL置信区间内定位到的基因进行功能注释。结果获得7个与大豆株高(PH)相关的QTL位点,3个与主茎节数(NN)相关的QTL位点。其中,qNN-20-1,qPH-4-1,qPH-6-1,qPH-19-1及qPH-20-1与前人研究结果相近或重合,qNN-7-1,qNN-7-2,qPH-9-1,qPH-12-1和qPH-19-2为新发现的位点,并且qNN-20-1与qPH-20-1存在重叠区域。依赖基因注释结果在位点内筛得32个候选基因,表明这些位点参与细胞进程及植物激素协调网络,进而导致株高或主茎节数的变化。研究结果将为大豆株型改良种提供理论依据,为剖析株高和主茎节数的遗传机制奠定理论基础。 展开更多
关键词 大豆 株高 主茎节数 QTL定位 候选基因
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壁面剪切流亚临界转捩的-1/2标度律与鞍结点分岔机制
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作者 陶建军 关家顺 张林森 《气体物理》 2025年第6期92-100,共9页
管流、槽流等壁面剪切流的亚临界转捩过程常常以局地湍流结构为先导。通过直接数值模拟与流体动力学分析,讨论了二维槽流、方管管流和圆管管流亚临界转捩特征结构寿命的统计特性,发现其转捩动力学过程存在共性,低于临界值时转捩特征结... 管流、槽流等壁面剪切流的亚临界转捩过程常常以局地湍流结构为先导。通过直接数值模拟与流体动力学分析,讨论了二维槽流、方管管流和圆管管流亚临界转捩特征结构寿命的统计特性,发现其转捩动力学过程存在共性,低于临界值时转捩特征结构的寿命随Reynolds数存在-1/2标度律。通过提出保形近似并将其应用于扰动动能方程,推导出了控制转捩的鞍结点分岔类方程,从而可从理论上预测3种流动的临界Reynolds数,预测值同各自的数值模拟结果相符,而低Reynolds数的-1/2标度律正是由鞍结点分岔在亚临界区的临界慢化现象决定的。 展开更多
关键词 亚临界转捩 槽流 管流 标度律 鞍结点分岔 临界Reynolds数
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基于株高和主茎节数的大豆抗旱性全基因组关联分析 被引量:1
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作者 石岱 扎比热 +5 位作者 孙玲玲 曲雪 孙明明 周润南 赵长江 任洪雷 《大豆科学》 北大核心 2025年第3期51-60,I0001-I0006,共16页
为探究大豆基于株高抗旱系数(drought resistance coefficient based on plant height,DCPH)和主茎节数抗旱系数(drought resistance coefficient based on number of main stem nodes,DCNS)的抗性遗传基础,本研究选取由113份大豆品种(... 为探究大豆基于株高抗旱系数(drought resistance coefficient based on plant height,DCPH)和主茎节数抗旱系数(drought resistance coefficient based on number of main stem nodes,DCNS)的抗性遗传基础,本研究选取由113份大豆品种(系)组成的自然群体作为研究材料,在全生育期干旱胁迫和正常供水条件下测定了株高和主茎节数,分别计算两种类型的抗旱系数,并利用全基因组关联分析技术(Genome-Wide Association Study,GWAS),挖掘与大豆株高和主茎节数抗旱性相关的基因和位点。结果显示:利用1882531个SNP标记进行GWAS分析,DCPH显著关联的位点全部位于9号染色体上,而DCNS显著关联的位点全部位于6号染色体上。进一步分析确定了DCPH和DCNS的候选基因区间,分别筛选出41个与DCPH相关的候选基因和15个与DCNS相关的候选基因。这些基因可能参与大豆生长发育的调控、激素信号传导、细胞分裂和生长等过程。本研究不仅为深入解析大豆抗旱性的分子机制提供了重要线索,还为培育抗旱性强的大豆品种提供了宝贵的基因资源。 展开更多
关键词 大豆 株高 主茎节数 全基因组关联分析 抗旱性
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269例甲状腺髓样癌临床病理特点及预后分析
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作者 王红群 李杰 +5 位作者 刘鹏 马亚琪 马志厚 巩幼洁 张阳阳 石怀银 《诊断病理学杂志》 2025年第7期829-837,共9页
目的探讨甲状腺髓样癌(MTC)的临床病理特点及分析影响预后的因素。方法收集269例MTC的临床病理资料,随访预后,并统计学分析。结果269例MTC患者中男性占49.8%,淋巴结转移率62.9%,≥2灶占35.8%,67.3%≦2 cm,27.1%集中在41~50岁年龄段,远... 目的探讨甲状腺髓样癌(MTC)的临床病理特点及分析影响预后的因素。方法收集269例MTC的临床病理资料,随访预后,并统计学分析。结果269例MTC患者中男性占49.8%,淋巴结转移率62.9%,≥2灶占35.8%,67.3%≦2 cm,27.1%集中在41~50岁年龄段,远处转移率7.4%,随访期总体死亡率9.6%,术后/治疗后的复发率14.8%。免疫组化显示:TTF-1(99.0%+),Calcitonin(85.4%+),Syn(98.7%+),CgA(81.9%+),CEA(88.8%+),Ki-67显示95.1%≤10%阳性。分期晚、更大的最大径、有被膜侵犯、有癌栓、复发癌患者及有MEN2/家族史更易发生多灶,多灶者术后易复发(均P<0.05)。5年、10年及14年的总体生存率分别为(90.0±0.03)%,(80.0±0.05)%及(80.0±0.05)%。单因素生存分析显示淋巴结转移、年龄大、TNM分期晚、侵犯被膜程度、有脉管内癌栓、远处转移及术后/治疗后的复发转移均影响总生存时间(OS)。在多因素分析中,有远处转移、淋巴结转移及侵犯被膜影响无复发生存时间。MTC的OS仅次于甲状腺乳头状癌组。结论年龄大、有远处转移和癌栓是影响MTC的独立预后因素,MTC预后较好。 展开更多
关键词 甲状腺髓样癌 临床病理特点 预后 淋巴结转移 肿瘤灶数
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农田监测无线传感器网络节点部署策略
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作者 程晓玲 郭小春 严锡君 《微型电脑应用》 2025年第10期11-15,共5页
无线传感器网络的节点优化部署可提高网络的覆盖率、延长网络生命周期。针对农田监测,结合链型网络和星型网络的特点,提出一种多链型无线传感器网络节点优化部署策略。综合考虑链间干扰、网络连通性和节点能耗,得到节点最优间距、每条... 无线传感器网络的节点优化部署可提高网络的覆盖率、延长网络生命周期。针对农田监测,结合链型网络和星型网络的特点,提出一种多链型无线传感器网络节点优化部署策略。综合考虑链间干扰、网络连通性和节点能耗,得到节点最优间距、每条链的最优跳数以及圆形区域最优链数。MATLAB仿真说明,所提出部署方法能够有效地降低、均衡节点能耗、最大限度地延长网络的生命周期。 展开更多
关键词 无线传感器网络 节点部署 最优间距 最优链数 农田监测
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矮秆基因在大豆育种中的研究进展
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作者 赵晓晖 赵苗羽 +2 位作者 何佳薇 黄乐香 刘宝辉 《广东农业科学》 2025年第7期21-33,共13页
大豆作为全球重要的粮油饲兼用作物,其产量水平直接关系国家粮食安全与农业可持续发展。株高是大豆株型中的关键产量构成因子,通过主茎节数与节间长度的协同调控,显著影响单株荚数形成、种植密度优化、抗倒伏能力提升与产量潜力挖掘。... 大豆作为全球重要的粮油饲兼用作物,其产量水平直接关系国家粮食安全与农业可持续发展。株高是大豆株型中的关键产量构成因子,通过主茎节数与节间长度的协同调控,显著影响单株荚数形成、种植密度优化、抗倒伏能力提升与产量潜力挖掘。尽管水稻、小麦等主粮作物已通过半矮秆品种选育成功实现产量飞跃,并引发“绿色革命”,但大豆单产水平却长期停滞不前,这凸显出半矮秆基因挖掘及其分子机制解析在大豆育种应用中的紧迫性。该文系统综述大豆株高构成因子中主茎节数与节间长度的遗传基础及其分子调控网络。一方面全面总结大豆株型特异的茎生长习性控制基因及其所处的分子通路,主要包括Dt1与Dt2基因在茎顶端分生组织中的表达特征及其对有限型、亚有限型和无限型茎生长习性的调控作用,并探讨不同茎生长习性与生态适应性的关联性;在分子调控层面,大豆生长点中形成以Dt1与Dt2为核心的复杂调控网络,整合多基因与多信号分子实现对大豆株高的调控。另一方面,该文重点综述赤霉素、生长素及油菜素甾醇等关键植物激素信号通路在大豆株高调控方面的最新研究进展,赤霉素途径的研究主要集中在生物合成、代谢调控及信号转导方面的分子机制,油菜素甾醇则被发现通过调控株型结构显著提升大豆产量潜力。基于大豆独特的株型特性与基因组的复杂性,该文进一步从分子设计育种角度展望大豆半矮秆育种与产量提升的潜在路径,以期为大豆利用半矮秆基因进行遗传改良和种质创新提供一定的理论基础。 展开更多
关键词 大豆 株高 矮秆 主茎节数 节间长度 分子机制
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应急突发事件下配电网安全承载能力评估
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作者 李佳宇 王建军 +4 位作者 刘彦超 刘杰 李浩 江俊杰 滕佳伦 《哈尔滨理工大学学报》 北大核心 2025年第2期114-121,共8页
随着分布式电源与储能设备的广泛应用,配电网呈现出更多未知的特性。而电力系统中应急突发事件对电网的稳定安全运行构成重大威胁。为了分析配电网的安全承载能力,首先依据M-阶邻居数与熵理论,构造节点影响力指标。其次,在考虑了应急突... 随着分布式电源与储能设备的广泛应用,配电网呈现出更多未知的特性。而电力系统中应急突发事件对电网的稳定安全运行构成重大威胁。为了分析配电网的安全承载能力,首先依据M-阶邻居数与熵理论,构造节点影响力指标。其次,在考虑了应急突发事件对潮流分布的影响后,提出了一种考虑电网潮流分布均衡度的安全承载能力评估方法,并提出一种基于迭代法的关键安全约束选取策略,使得在优化模型中仅考虑关键安全约束即可满足所有潮流可行性,提高了求解效率。最后,将评估模型用在IEEE33节点测试系统进行分析,验证了所提方法在分析应急突发事件中配电网安全承载能力的同时,又能保证经济性,符合当下配电网的发展需求。 展开更多
关键词 承载能力 节点影响力指标 M-阶邻居数 安全约束 潮流分布均衡度
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