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The sow vaginal and gut microbiota associated with longevity and reproductive performance 被引量:1
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作者 Ziyu Liu Tsungcheng Tsai +5 位作者 Bin Zuo Samantha Howe Jason EFarrar Christopher ERandolph Charles VMaxwell Jiangchao Zhao 《Journal of Animal Science and Biotechnology》 2025年第2期577-595,共19页
Background Sow longevity and reproductivity are essential in the modern swine industry.Although many studies have focused on the genetic and genomic factors for selection,little is known about the associations between... Background Sow longevity and reproductivity are essential in the modern swine industry.Although many studies have focused on the genetic and genomic factors for selection,little is known about the associations between the microbiome and sows with longevity in reproduction.Results In this study,we collected and sequenced rectal and vaginal swabs from 48 sows,nine of which completed up to four parities(U4P group),exhibiting reproductive longevity.We first identified predictors of sow longevity in the rectum(e.g.,Akkermansia)and vagina(e.g.,Lactobacillus)of the U4P group using RandomForest in the early breeding stage of the first parity.Interestingly,these bacteria in the U4P group showed decreased predicted KEGG gene abundance involved in the biosynthesis of amino acids.Then,we tracked the longitudinal changes of the micro-biome over four parities in the U4P sows.LEfSe analysis revealed parity-associated bacteria that existed in both the rectum and vagina(e.g.,Streptococcus in Parity 1,Lactobacillus in Parity 2,Veillonella in Parity 4).We also identi-fied patterns of bacterial change between the early breeding stage(d 0)and d 110,such as Streptococcus,which was decreased in all four parties.Furthermore,sows in the U4P group with longevity potential also showed better reproductive performance.Finally,we discovered bacterial predictors(e.g.,Prevotellaceae NK3B31 group)for the total number of piglets born throughout the four parities in both the rectum and vagina.Conclusions This study highlights how the rectal and vaginal microbiome in sows with longevity in reproduc-tion changes within four parities.The identification of parity-associated,pregnancy-related,and reproductive performance-correlated bacteria provides the foundation for targeted microbiome modulation to improve animal production. 展开更多
关键词 LONGEVITY Parity Rectal microbiome Reproductive performance SOWS Vaginal microbiome
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Measurement-based entanglement purification for hybrid entangled state
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作者 Cheng-Chen Luo Shi-Pu Gu +2 位作者 Xing-Fu Wang Lan Zhou Yu-Bo Sheng 《Chinese Physics B》 2025年第3期104-114,共11页
Hybrid entangled states(HESs),which involve different particles with various degrees of freedom,have garnered significant attention and been applied in a wide range of quantum technologies.However,similar to other cat... Hybrid entangled states(HESs),which involve different particles with various degrees of freedom,have garnered significant attention and been applied in a wide range of quantum technologies.However,similar to other categories of entanglement,maximally HESs inevitably degrade to mixed states due to the environmental noise and operational imperfections.To address the degradation problem,measurement-based entanglement purification offers a feasible and robust solution alternative to conventional gate-based purification methods.In this paper,we propose a measurement-based hybrid entanglement purification protocol(MB-HEPP)for a certain kind of HES which consists of polarization photons and coherent states.We extend our methodology to several conditions,such as the multi-copy and multi-party scenarios,and the photon-loss condition.Compared with previous HEPPs,this protocol has several advantages.First,it does not depend on post-selection and the purified HESs can be retained for further application.Second,it does not require the Bell state measurement,but only uses the parity check with conventional linear optical elements,which makes it have the higher success probability and more feasible.Our MB-HEPP has potential applications in future heterogeneous quantum networks. 展开更多
关键词 hybrid entanglement measurement-based entanglement purification parity check
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基于Fama-French五因子风险分散投资策略
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作者 叶钰怡 毛昱皓 卢彦翰 《合作经济与科技》 2025年第2期50-54,共5页
全球经济环境复杂多变,各国股市频繁波动,分散化投资策略成为投资者关注的重点。本文选取Fama-French五因子模型作为研究工具,选取2000年1月至2023年12月月度数据,剔除非蓝筹股,以确保数据稳定性,并通过清洗和预处理选取242只蓝筹股作... 全球经济环境复杂多变,各国股市频繁波动,分散化投资策略成为投资者关注的重点。本文选取Fama-French五因子模型作为研究工具,选取2000年1月至2023年12月月度数据,剔除非蓝筹股,以确保数据稳定性,并通过清洗和预处理选取242只蓝筹股作为样本。选出各因子影响程度较大前十家企业作为投资组合备选股,构建投资组合时采用风险预算平价Risk Parity方法进行优化。回测结果证明该策略在A股市场的有效性,为追求低风险的稳健长期投资者提供新的思路。 展开更多
关键词 风险分散 Fama-French五因子 风险预算平价Risk Parity
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Interactions between maternal parity and feed additives drive the composition of pig gut microbiomes in the post‑weaning period
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作者 Kayla Law Eduardo Rosa Medina Garcia +3 位作者 Chad Hastad Deborah Murray Pedro E.Urriola Andres Gomez 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第3期1241-1257,共17页
Background Nursery pigs undergo stressors in the post-weaning period that result in production and welfare chal-lenges.These challenges disproportionately impact the offspring of primiparous sows compared to those of ... Background Nursery pigs undergo stressors in the post-weaning period that result in production and welfare chal-lenges.These challenges disproportionately impact the offspring of primiparous sows compared to those of mul-tiparous counterparts.Little is known regarding potential interactions between parity and feed additives in the post-weaning period and their effects on nursery pig microbiomes.Therefore,the objective of this study was to investigate the effects of maternal parity on sow and offspring microbiomes and the influence of sow parity on pig fecal microbi-ome and performance in response to a prebiotic post-weaning.At weaning,piglets were allotted into three treat-ment groups:a standard nursery diet including pharmacological doses of Zn and Cu(Con),a group fed a commercial prebiotic only(Preb)based on an Aspergillus oryzae fermentation extract,and a group fed the same prebiotic plus Zn and Cu(Preb+ZnCu).Results Although there were no differences in vaginal microbiome composition between primiparous and mul-tiparous sows,fecal microbiome composition was different(R^(2)=0.02,P=0.03).The fecal microbiomes of primiparous offspring displayed significantly higher bacterial diversity compared to multiparous offspring at d 0 and d 21 post-weaning(P<0.01),with differences in community composition observed at d 21(R^(2)=0.03,P=0.04).When analyzing the effects of maternal parity within each treatment,only the Preb diet triggered significant microbiome distinc-tions between primiparous and multiparous offspring(d 21:R^(2)=0.13,P=0.01;d 42:R^(2)=0.19,P=0.001).Composi-tional differences in pig fecal microbiomes between treatments were observed only at d 21(R^(2)=0.12,P=0.001).Pigs in the Con group gained significantly more weight throughout the nursery period when compared to those in the Preb+ZnCu group.Conclusions Nursery pig gut microbiome composition was influenced by supplementation with an Aspergillus oryzae fermentation extract,with varying effects on performance when combined with pharmacological levels of Zn and Cu or for offspring of different maternal parity groups.These results indicate that the development of nursery pig gut microbiomes is shaped by maternal parity and potential interactions with the effects of dietary feed additives. 展开更多
关键词 Aspergillus prebiotic Copper Feed additives MATERNAL Nursery pig microbiome PARITY Swine microbiome Trace minerals Zinc
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Majorana tunneling in a one-dimensional wire with non-Hermitian double quantum dots
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作者 牛鹏斌 罗洪刚 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期686-691,共6页
The combination of non-Hermitian physics and Majorana fermions can give rise to new effects in quantum transport systems. In this work, we investigate the interplay of PT-symmetric complex potentials, Majorana tunneli... The combination of non-Hermitian physics and Majorana fermions can give rise to new effects in quantum transport systems. In this work, we investigate the interplay of PT-symmetric complex potentials, Majorana tunneling and interdot tunneling in a non-Hermitian double quantum dots system. It is found that in the weak-coupling regime the Majorana tunneling has pronounced effects on the transport properties of such a system, manifested as splitting of the single peak into three and a reduced 1/4 peak in the transmission function. In the presence of the PT-symmetric complex potentials and interdot tunneling, the 1/4 central peak is robust against them, while the two side peaks are tuned by them. The interdot tunneling only induces asymmetry, instead of moving the conductance peak, due to the robustness of the Majorana modes. There is an exceptional point induced by the union of Majorana tunneling and interdot tunneling. With increased PT-symmetric complex potentials, the two side peaks will move towards each other. When the exceptional point is passed through, these two side peaks will disappear. In the strong-coupling regime, the Majorana fermion induces a 1/4 conductance dip instead of the three-peak structure. PT-symmetric complex potentials induce two conductance dips pinned at the exceptional point. These effects should be accessible in experiments. 展开更多
关键词 Majorana fermion non-Hermitian quantum dot parity–time symmetry exceptional point
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Heteronuclear Magnetisms with Ultracold Spinor Bosonic Gases in Optical Lattices
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作者 Yongqiang Li Chengkun Xing +2 位作者 Ming Gong Guangcan Guo Jianmin Yuan 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第2期69-82,共14页
Motivated by recent realizations of spin-1 NaRb mixtures in the experiments[Phys.Rev.Lett.114,255301(2015);Phys.Rev.Lett.128,223201(2022)],we investigate heteronuclear magnetism in the Mott-insulating regime.Different... Motivated by recent realizations of spin-1 NaRb mixtures in the experiments[Phys.Rev.Lett.114,255301(2015);Phys.Rev.Lett.128,223201(2022)],we investigate heteronuclear magnetism in the Mott-insulating regime.Different from the identical mixtures where the boson statistics only admits even parity states from angular momentum composition,for heteronuclear atoms in principle all angular momentum states are allowed,which can give rise to new magnetic phases.While various magnetic phases can be developed over these degenerate spaces,the concrete symmetry breaking phases depend on not only the degree of degeneracy but also the competitions from many-body interactions.We unveil these rich phases using the bosonic dynamical mean-field theory approach.These phases are characterized by various orders,including spontaneous magnetization order,spin magnitude order,singlet pairing order,and nematic order,which may coexist specially in the regime with odd parity.Finally we address the possible parameter regimes for observing these spin-ordered Mott phases. 展开更多
关键词 PARITY MOMENTUM allowed
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Static or dynamic pear shapes in radioactive nucleus ^(224)Rn?
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作者 Xian-Ye Wu Jin-Ze Cao +3 位作者 Kun-Ning Zhao Zhong-Min Liu Jian Xiang En-Fu Zhou 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第11期164-173,共10页
We report a comprehensive study on low-lying parity doublet states of ^(224)Rn by mixing both quadrupole-and octupoleshaped configurations in multireference covariant density functional theory,in which broken symmetri... We report a comprehensive study on low-lying parity doublet states of ^(224)Rn by mixing both quadrupole-and octupoleshaped configurations in multireference covariant density functional theory,in which broken symmetries in configurations are restored using projection techniques.The low-lying energy spectrum is reasonably reproduced when the shape fluctuations in both the quadrupole and octupole shapes are considered.Electric octupole transition strength in ^(224)Rn is found to be B(E3;3_(1)^(-)→0_(1)^(+))=43 W.u.,comparable to that in ^(224)Ra,whose data are 42(3)W.u..Our results indicate that ^(224)Rn shares similar low-energy structure with ^(224)Ra despite the excitation energy of first 3^(−)state of the former nucleus is higher than that of the latter.This study suggests ^(224)Rn is a candidate for the search for permanent electric dipole moment. 展开更多
关键词 Covariant density functional theory Parity doublet bands Octupole correlations Electric transition strengths
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P_(c)(4457)Interpreted as a J^(P)=1/2+State by D^(0)∧_(c)^(+)(2595)-π^(0)P_(c)(4312) Interaction
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作者 Jin-Zi Wu Jin-Yi Pang Jia-Jun Wu 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第9期23-27,共5页
P_(c)(4457)has been discovered over five years,but the parity of this particle remains undetermined.We propose a new interpretation for P_(c)(4457),which is the state generated from the coupled-channel D^(0)Ac+(2595)... P_(c)(4457)has been discovered over five years,but the parity of this particle remains undetermined.We propose a new interpretation for P_(c)(4457),which is the state generated from the coupled-channel D^(0)Ac+(2595)andπ^(0)P_(c)(4312)since they can exchange an almost on-shell∑_(c)^(+).In this scenario,the parity of P_(c)(4457)will be positive,which is different from the candidate of the bound state of D*∑_(c).The main decay channel of P_(c)(4457)in this model is Pc(4312)π.We propose three processes∧_(b)^(0)→J/ψKapπ^(-),∧_(b)^(0)→J/ψK-pπ^(0),and∧_(b)^(0)→J/ψpπ^(-)π^(+)k^(-)to verify Pc(4457)→Pc(4312)π. 展开更多
关键词 PARITY verify
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Multi-Quantifying Maxillofacial Traits via a Demographic Parity-Based AI Model
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作者 Mengru Shi Zhuohong Gong +8 位作者 Peisheng Zeng Dawei Xiang Gengbin Cai Hengyi Liu Shijie Chen Runheng Liu Zhuofan Chen Xinchun Zhang Zetao Chen 《Biomedical Engineering Frontiers》 2024年第1期159-169,共11页
Objective and Impact Statement:The multi-quantification of the distinct individualized maxillofacial traits,that is,quantifying multiple indices,is vital for diagnosis,decision-making,and prognosis of the maxillofacia... Objective and Impact Statement:The multi-quantification of the distinct individualized maxillofacial traits,that is,quantifying multiple indices,is vital for diagnosis,decision-making,and prognosis of the maxillofacial surgery.Introduction:While the discrete and demographically disproportionate distributions of the multiple indices restrict the generalization ability of artificial intelligence(AI)-based automatic analysis,this study presents a demographic-parity strategy for AI-based multi-quantification.Methods:In the aesthetic-concerning maxillary alveolar basal bone,which requires quantifying a total of 9 indices from length and width dimensional,this study collected a total of 4,000 cone-beam computed tomography(CBCT)sagittal images,and developed a deep learning model composed of a backbone and multiple regression heads with fully shared parameters to intelligently predict these quantitative metrics.Through auditing of the primary generalization result,the sensitive attribute was identified and the dataset was subdivided to train new submodels.Then,submodels trained from respective subsets were ensembled for final generalization.Results:The primary generalization result showed that the AI model underperformed in quantifying major basal bone indices.The sex factor was proved to be the sensitive attribute.The final model was ensembled by the male and female submodels,which yielded equal performance between genders,low error,high consistency,satisfying correlation coefficient,and highly focused attention.The ensemble model exhibited high similarity to clinicians with minor processing time.Conclusion:This work validates that the demographic parity strategy enables the AI algorithm with greater model generalization ability,even for the highly variable traits,which benefits for the appearance-concerning maxillofacial surgery. 展开更多
关键词 maxillofacial traits gender sensitivity demographic parity artificial intelligence multi quantification model generalization artificial intelligence ai based multiple indicesis
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RAIM算法研究 被引量:10
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作者 秘金钟 李毓麟 +1 位作者 LI Yu-lin 《测绘通报》 CSCD 北大核心 2001年第3期7-9,共3页
用户自主式完备性监测 RAIM算法是广域差分 GPS的关键和核心技术之一。在已有 RAIM算法的基础上 ,讨论了粗差探测和定位的方法 ,并给出了 Parity方法中剔除多个粗差的算法 ,最后用 ' 99南海实测数据进行了验证。
关键词 广域差分 完备性监测 RAIM算法 Parity方法 用户自主式完备性监测 粗差 GPS定位
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Solvability Condition for Robust Stabilization Problem of Control Systems with Parameter Uncertainties 被引量:1
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作者 伍清河 《Journal of Beijing Institute of Technology》 EI CAS 1999年第3期258-263,共6页
Aim The solvability condition for robust stabilization problem associated with a plant family P(s,δ) having parameter uncertainty δ was considered. Methods Using Youla parameterization of the stabilizers this pro... Aim The solvability condition for robust stabilization problem associated with a plant family P(s,δ) having parameter uncertainty δ was considered. Methods Using Youla parameterization of the stabilizers this problem was transformed into a strong stabilization problem associated with a related plant family G (s, δ). Results A necessary solvability condition was established in terms of the parity interlacing property of each element in G(s,δ). Another apparently necessary solvability condition is that every element in P(s,δ) must be stabilizable. Conclusion The two conditions will be compared with each other and it will be shown that every element in G(s,δ) possesses parity interlacing property if P(s,δ) is stabilizable. 展开更多
关键词 robust stabilization parameter uncertainties strong stabilization parity interlacing property
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文化壁垒、政府价值取向与实际汇率波动 被引量:1
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作者 张保林 《会计与经济研究》 北大核心 2014年第4期83-90,共8页
通过博弈分析发现,在商品和生产要素自由流通、两国市场规模相同、完全信息和产品同质假定下,两国居民对待进口产品的态度不同,或两国政府在经济增长速度和保障就业水平两个目标上的偏好不同,将导致两国产品具有不同的价格水平,进而导... 通过博弈分析发现,在商品和生产要素自由流通、两国市场规模相同、完全信息和产品同质假定下,两国居民对待进口产品的态度不同,或两国政府在经济增长速度和保障就业水平两个目标上的偏好不同,将导致两国产品具有不同的价格水平,进而导致实际汇率偏离购买力平价。消费文化和政府经济调控目标差异对实际汇率有一定影响。 展开更多
关键词 实际汇率 文化壁垒 政府价值取向 购买力平价 Pur-chasing Power PARITY (PPP)
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PT对称光晶格中的缺陷暗孤子
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作者 易向东 谢庆文 +3 位作者 罗质华 石智伟 朱兴 李华刚 《量子电子学报》 CAS CSCD 北大核心 2015年第6期728-734,共7页
数值研究了实部具有缺陷的parity-time(PT)对称光晶格中的缺陷暗孤子。当衍射与自散焦非线性效应平衡时,暗孤子能够被获得;当自散焦介质中的PT对称光晶格实都被附加一个缺陷后,缺陷暗孤子也能够被获得。数值结果显示:缺陷暗孤子可以在... 数值研究了实部具有缺陷的parity-time(PT)对称光晶格中的缺陷暗孤子。当衍射与自散焦非线性效应平衡时,暗孤子能够被获得;当自散焦介质中的PT对称光晶格实都被附加一个缺陷后,缺陷暗孤子也能够被获得。数值结果显示:缺陷暗孤子可以在很大参数范围内存在并能稳定传播;PT对称光晶格实部附加的缺陷强度有一最大值,超过此值缺陷暗孤子不存在;PT对称光晶格的虚部振幅对缺陷暗孤子的稳定性有影响。 展开更多
关键词 非线性光学 缺陷暗孤子 parity—time对称光晶格 稳定性
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A Journey into Fermat's Equation 被引量:1
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作者 Mario De Paz Enzo Bonacci 《Journal of Mathematics and System Science》 2012年第9期539-544,共6页
As expounded in some recent mathematical conferences, this research on that amazing source of algebraic ideas known as Fermat's equation is aimed to prove how Fermat triples can be limited until the impossible existe... As expounded in some recent mathematical conferences, this research on that amazing source of algebraic ideas known as Fermat's equation is aimed to prove how Fermat triples can be limited until the impossible existence through a criterion of incompatible parities related to unexplored properties of the binomial coefficients. In this paper, the authors use a technique based on the analysis of four numbers and their internal relations with three basic compulsory factors. It leads to the practical impossibility to find any triple of natural numbers candidate to satisfy Fermat's equation, because when the authors try to meet a condition between parity and range the authors are compelled to violate the other one, so that they are irreducibly alternative. In particular, there is a parity violation when the authors choose all the basic factors in the allowed range and the authors obtain exceeding values of one of the involved variables when the authors try to restore the parity. Since Fermat's last theorem would consequently be demonstrated, many readers could recall the never found elementary proof of FLT (Fermat's last theorem) claimed by Pierre de Fermat. The authors are not encouraging such an interpretation because this paper is intended as a journey into Fermat's equation and the reader's attitude should be towards the algebraic achievements here proposed, with their possible hidden flaws and future developments, rather than to legendary problems like Fermat's riddle. 展开更多
关键词 Fermat's equation binomial coefficients incompatible parities Fermat's last theorem Fermat's little theorem.
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GPS自主完整性监测算法研究
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作者 廉保旺 张亮 曹娜 《电子测量技术》 2007年第10期26-28,共3页
完整性检测是GPS的重要技术问题之一,传统RAIM算法有最小二乘法和Parity法等,大多在分离多颗故障卫星时的效果不佳,本文在对卫星导航系统中现有RAIM算法进行研究的基础上,讨论了故障卫星的探测与分离方法,提出了一种将传统算法有效结合... 完整性检测是GPS的重要技术问题之一,传统RAIM算法有最小二乘法和Parity法等,大多在分离多颗故障卫星时的效果不佳,本文在对卫星导航系统中现有RAIM算法进行研究的基础上,讨论了故障卫星的探测与分离方法,提出了一种将传统算法有效结合的新算法,该算法能有效探测和分离多颗故障卫星。通过对各种不同的算法进行仿真,并对仿真结果进行对比,证明该算法具有能准确分离故障卫星和实时性强等优点。 展开更多
关键词 完整性检测 RAIM PARITY
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Modified Benes network architecture for WiMAX LDPC decoder 被引量:1
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作者 徐勐 吴建辉 张萌 《Journal of Southeast University(English Edition)》 EI CAS 2011年第2期140-143,共4页
A modified Benes network is proposed to be used as an optimal shuffle network in worldwide interoperability for microwave access (WiMAX) low density parity check (LDPC) decoders, When the size of the input is not ... A modified Benes network is proposed to be used as an optimal shuffle network in worldwide interoperability for microwave access (WiMAX) low density parity check (LDPC) decoders, When the size of the input is not a power of two, the modified Benes network can achieve the most optimal performance. This modified Benes network is non-blocking and can perform any sorts of permutations, so it can support 19 modes specified in the WiMAX system. Furthermore, an efficient algorithm to generate the control signals for all the 2 × 2 switches in this network is derived, which can reduce the hardware complexity and overall latency of the modified Benes network. Synthesis results show that the proposed control signal generator can save 25.4% chip area and the overall network latency can be reduced by 36. 2%. 展开更多
关键词 worldwide interoperability for microwave access(WiMAX) quasi-cycle low density parity check (QC-LDPC) LDPC decoder Benes network
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Effect of Cesarean Section on the Severity of Postpartum Hemorrhage in Chinese Women: The Shanxi Study 被引量:25
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作者 Chang XU Qiang FU +4 位作者 Hong-bing TAO Xiao-jun LIN Man-li WANG Shu-xu XIA Hao-ling XIONG 《Current Medical Science》 SCIE CAS 2018年第4期618-625,共8页
Postpartum hemorrhage (PPH) is one of the most adverse obstetric outcomes. Our aim is to detect the risks of multilevel PPH in different cesarean section (CS) groups [including nulliparous CS with indications, nul... Postpartum hemorrhage (PPH) is one of the most adverse obstetric outcomes. Our aim is to detect the risks of multilevel PPH in different cesarean section (CS) groups [including nulliparous CS with indications, nulliparous CS without indications, repeat cesarean (RC), vaginal birth after cesarean (VBAC), cesarean after vaginal birth (CAVB)]. We conducted a retrospective cohort study, and the data on 127 145 women collected from January 2014 to May 2016 and from 35 tertiary hospitals in Shanxi province, China, were reviewed. Based on the measuring results of PPH, an ordered logistic regression model was used to analyze the adjusted PPH risks for each of the CS groups, and comparisons were drawn between them. Finally, a total of 99 066 nulliparous (77.92%) and 28 079 multiparous (22.08%) women were observed. The number of CS cases was 61 117, and the rate for CS was 48.07%. A total of 10 029 women did not show indications for CS and accounted for 16.41% of the CS parturient, whereas 9103 women underwent a repeated cesarean, with a CS frequency of 14.89%. The number of VBAC cases was 989, whose rate was 9.88% in prior CS women. The number (proportions) of PPH was 3658 (2.88%) in L1 (PPH volume: ≥900 and 〈1500 mL), 520 (0.41%) in L2 (PPH volume: ≥1500 and〈2100 mL), and 201 (0.16%) in L3 (PPH volume: ≥2100 mL). The Ln (n= 1, 2, 3, etc.) represented the increasing order of PPH severity. In the adjusted results, compared with spontaneous vaginal delivery (SVD) as the reference group, in the adjusted result for nulliparous, there was a decreased PPH risk in CS with indications (OR: 2.32; CI: 2.04-2.62), which was lower than that of CS without indications (OR: 2.50; CI: 2.01-2.96). The highest PPH risk in all subgroups (i.e. nulliparous and multiparous groups) was observed in the RC (OR: 3.61; CI: 3.16-4.17), which was nearly twice higher than that of the VBAC (OR: 1.82; CI: 1.33-2.52). CAVB (OR: 1.03; CI: 0.65-1.62) showed no significant difference with the reference group. Thus, we deemed that CS should be avoided in nulliparous pregnancies unless indicated, to prevent or reduce the rates for the use of RC or VBAC which are high risks of severe PPH to the parturient women. 展开更多
关键词 postpartum hemorrhage cesarean section PARITY INDICATIONS
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A comparison of maternal fear of childbirth,labor pain intensity and intrapartum analgesic consumption between primiparas and multiparas:A cross-sectional study 被引量:15
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作者 Yongfang Deng Yan Lin +5 位作者 Liyuan Yang Qiuxia Liang Bailing Fu Huixian Li Huizhu Zhang Yan Liu 《International Journal of Nursing Sciences》 CSCD 2021年第4期380-387,I0002,共9页
Objectives:To describe and compare fear of childbirth and in-labor pain intensity between primiparas and multiparas and explore the association between the amount of actual pain relief and fear of childbirth.Methods:A... Objectives:To describe and compare fear of childbirth and in-labor pain intensity between primiparas and multiparas and explore the association between the amount of actual pain relief and fear of childbirth.Methods:A convenience sampling method was used.A total of 260 women undergoing spontaneous or induced labor,including 97 primiparas and 163 multiparas,were recruited in a large academic specialized hospital in Guangzhou,China,from February 2018 to August 2019.The clinical data of maternal and neonatal were extracted from a structured electronic medical record system.Other demographic information,such as employment and family monthly income,was collected by a questionnaire.The Numeric Rating Scale(NRS)and the Chinese version of the Childbirth Attitude Questionnaire(C-CAQ)were applied to assess maternal in-labor pain intensity and fear of childbirth.The analgesic consumption and the frequency of manual boluses as rescue analgesia were stored and collected from the analgesia pump.Results:Eighty-two(84.5%)primiparas and ninety-nine(60.7%)multiparas received epidural analgesia(P<0.001).In the epidural subgroup,the primiparous average fear of childbirth(36.46±10.93)was higher than that of the multiparas(32.06±10.23)(P¼0.007).However,multiparas reported more intense in-labor pain[8.0(8.0,9.0)vs.8.0(7.0,8.0)],had more successful manual boluses per hour[2.68(1.65,3.85)vs.1.77(0.90,2.47)],more hourly analgesic consumption[23.00(16.00,28.25)vs.17.24(11.52,21.36)mL]and more average analgesic consumption[0.35(0.24,0.45)vs.0.26(0.19,0.35)mL/(h$kg)]than the primiparas(P<0.05).Spearman’s correlation analysis showed that the maximum in-labor pain was weakly positively correlated with fear of childbirth(r¼0.09)(P<0.05),hourly analgesic consumption(r¼0.16)(P<0.01)and average analgesic consumption(r¼0.17)(P<0.05).No statistically significant association was uncovered between analgesic consumption and maternal fear of childbirth.Conclusions:Fear of childbirth is a potential predictor of labor pain intensity.Further study is needed to explore its role and value in pain management during delivery.Parity is not a determinant of pain relief use and should not be a preconceived preference of obstetric care team members to determine the distribution of epidural analgesia,especially when analgesia resources are insufficient. 展开更多
关键词 Epidural analgesia FEAR Labor pain Obstetrics and gynecology department of the hospital Parity PARTURITION
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Design of Irregular QC-LDPC Code Based Multi-Level Coded Modulation Scheme for High Speed Optical Communication Systems 被引量:7
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作者 Liqian Wang Dongdong Wang +3 位作者 Yongjing Ni Xue Chen Midou Cui Fu Yang 《China Communications》 SCIE CSCD 2019年第5期106-120,共15页
In this paper, we focus on the design of irregular QC-LDPC code based multi-level coded modulation(MLCM) scheme by jointly optimizing the component code rate and the degree distribution of the irregular QC-LDPC compon... In this paper, we focus on the design of irregular QC-LDPC code based multi-level coded modulation(MLCM) scheme by jointly optimizing the component code rate and the degree distribution of the irregular QC-LDPC component code. Firstly, the sub-channel capacities of MLCM systems is analyzed and discussed, based on which the optimal component code rate can be obtained. Secondly, an extrinsic information transfer chart based two-stage searching algorithm is proposed to find the good irregular QC-LDPC code ensembles with optimal component code rates for their corresponding sub-channels. Finally, by constructing the irregular QC-LDPC component codes from the designed ensembles with the aim of possibly enlarging the girth and reducing the number of the shortest cycles, the designed irregular QC-LDPC code based 16QAM and 64QAM MLCM systems can achieve 0.4 dB and 1.2 dB net coding gain, respectively, compared with the recently proposed regular QC-LDPC code based 16QAM and 64QAM MLCM systems. 展开更多
关键词 quasi-cyclic LOW-DENSITY parity check (QC-LDPC) code irregular extrinsic INFORMATION transfer(EXIT) chart generalized mutual information(GMI) MULTI-LEVEL coded modulation(MLCM)
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Equivalent low-order angular flux nonlinear finite difference equation of MOC transport calculation 被引量:6
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作者 Li-Xun Liu Chen Hao Yun-Lin Xu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2020年第12期139-151,共13页
The key issue in accelerating method of characteristics(MOC)transport calculations is in obtaining a completely equivalent low-order neutron transport or diffusion equation.Herein,an equivalent low-order angular flux ... The key issue in accelerating method of characteristics(MOC)transport calculations is in obtaining a completely equivalent low-order neutron transport or diffusion equation.Herein,an equivalent low-order angular flux nonlinear finite difference equation is proposed for MOC transport calculations.This method comprises three essential features:(1)the even parity discrete ordinates method is used to build a low-order angular flux nonlinear finite difference equation,and different boundary condition treatments are proposed;(2)two new defined factors,i.e.,the even parity discontinuity factor and odd parity discontinuity factor,are strictly defined to achieve equivalence between the low-order angular flux nonlinear finite difference method and MOC transport calculation;(3)the energy group and angle are decoupled to construct a symmetric linear system that is much easier to solve.The equivalence of this low-order angular flux nonlinear finite difference equation is analyzed for two-dimensional(2D)pin,2D assembly,and 2D C5G7 benchmark problems.Numerical results demonstrate that a low-order angular flux nonlinear finite difference equation that is completely equivalent to the pin-resolved transport equation is established. 展开更多
关键词 Angular flux EQUIVALENCE Even parity discrete ordinates method Nonlinear finite difference
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