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一种稳健的自适应图像平滑算法 被引量:25
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作者 芮杰 吴冰 +1 位作者 秦志远 山海涛 《中国图象图形学报(A辑)》 CSCD 北大核心 2005年第1期54-58,共5页
图像平滑作为去除图像中含有噪声的图像增强处理技术,是各种与图像有关软件中必不可少的功能模块。优秀的平滑算法应该在有效处理含有多种噪声的受污图像时,仍具备良好的图像细节保持能力。为了能够在有效地处理含有多种噪声的受污图像... 图像平滑作为去除图像中含有噪声的图像增强处理技术,是各种与图像有关软件中必不可少的功能模块。优秀的平滑算法应该在有效处理含有多种噪声的受污图像时,仍具备良好的图像细节保持能力。为了能够在有效地处理含有多种噪声的受污图像的同时保持图像细节,提出了一种结合非线性和线性滤波器的稳健平滑算法,该算法是在分析几种细节保持能力良好的平滑算法(梯度加权平滑、自适应中值滤波、稳健平滑、边缘保持滤波器)的基础上,通过吸收上述几种平滑算法细节保持效果较好的优点,结合它们各自对不同噪声的适应性而得到的。针对含有多种噪声的受污图像,用该算法进行了去噪试验,多次试验结果表明,该算法在稳健地处理这些受污图像的同时,仍可以保持良好的图像细节,同时该算法还可以稳健地处理复杂的含噪图像,且具备良好自适应性,可以为涉及图像处理的软件架构,提供相应的算法支持。 展开更多
关键词 图像平滑 平滑算法 边缘保持 稳健 自适应 软件架构 图像增强 噪声 滤波器 去噪
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基于不同O2O模式的实体零售商融合策略——以步步高集团、永辉超市、天虹商场调研为例 被引量:14
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作者 陈红华 徐芬 《中国流通经济》 CSSCI 北大核心 2017年第10期81-88,共8页
目前,我国实体零售商采用的O2O模式主要包括自建模式、借用模式、自建+借用模式三类。不同模式的典型代表企业受自身条件与外部环境影响,其O2O融合方式比较多样化,但均致力于对原有供应链体系的升级改造,并在战略资源、渠道功能、运行... 目前,我国实体零售商采用的O2O模式主要包括自建模式、借用模式、自建+借用模式三类。不同模式的典型代表企业受自身条件与外部环境影响,其O2O融合方式比较多样化,但均致力于对原有供应链体系的升级改造,并在战略资源、渠道功能、运行机制、营销策略、信息系统、组织文化等方面进行了重新构建或相应调整。不同O2O模式融合的关键点既有相同之处,也有不同特性。其中,自建模式融合的关键在于,整合线上线下资源;借用模式融合的关键在于,合理利用合作方资源;自建+借用模式融合的关键在于,协调自建与借用平台之间的关系。实体零售商应当根据自己的战略目标选择合适的融合方式,进而结合企业供应链资源、线上线下渠道资源以及品牌形象等自身条件采取有效的融合策略。 展开更多
关键词 实体零售商 线上线下融合 自建模式 借用模式 自建+借用模式
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保费调整模型的研究 被引量:9
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作者 荣喜民 《系统工程理论与实践》 EI CSCD 北大核心 2001年第6期68-72,共5页
在分析保险累积损失和有效投资的基础上 ,利用倒向随机微分微分方程 ,建立了以投资收益相支持的保险价格调整模型 ,并对两种常见类型的保险进行了保险价格调整分析 .对保险人通过投资改变其保险市场竞争地位有积极的作用 .最后 ,用释例... 在分析保险累积损失和有效投资的基础上 ,利用倒向随机微分微分方程 ,建立了以投资收益相支持的保险价格调整模型 ,并对两种常见类型的保险进行了保险价格调整分析 .对保险人通过投资改变其保险市场竞争地位有积极的作用 .最后 ,用释例进行了说明 . 展开更多
关键词 累积损失 保险定价 倒向随机微分方程
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KELEA: A Natural Energy That Seemingly Reduces Intermolecular Hydrogen Bonding in Water and Other Liquids 被引量:8
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作者 W. John Martin 《Open Journal of Biophysics》 2015年第3期69-79,共11页
The alternative cellular energy (ACE) pathway was initially identified as a non-immunological defense mechanism against virus infections. It is particularly relevant to the suppression of stealth adapted viruses, whic... The alternative cellular energy (ACE) pathway was initially identified as a non-immunological defense mechanism against virus infections. It is particularly relevant to the suppression of stealth adapted viruses, which are not normally recognized by the cellular immune system. Many of the methods able to enhance the ACE pathway are consistent with the transfer of a natural energy to the body’s fluids. Additional support for this premise is provided in this paper. The vapor pressure and rate of evaporation of activated water, ethanol and gasoline increase to beyond atmospheric pressure over time. The term KELEA (kinetic energy limiting electrostatic attraction) is proposed for a natural energy that increases the volatility of fluids, seemingly through the loosening of intermolecular hydrogen bonding. KELEA activated fluids have many potential health, agricultural and industrial applications, as well as providing the opportunity for fundamental research. 展开更多
关键词 Alternative Cellular ENERGY ACE Pathway Magnesium Oxide KELEA-Kinetic ENERGY Limiting Electrostatic ATTRACTION Vapor Pressure Volatility STEALTH adapted Viruses WATER Alcohol Gasoline KikoTM Technology EnercelTM HOMEOPATHY Neutral Red Dye LIDOCAINE
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Adapted Metrics for a Modified Coulomb/Newton’s Potential
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作者 Lucian M. Ionescu Cristina-Liliana Pripoae Gabriel Pripoae 《Journal of High Energy Physics, Gravitation and Cosmology》 2023年第4期1311-1355,共45页
Modified Theories of Gravity include spin dependence in General Relativity, to account for additional sources of gravity instead of dark matter/energy approach. The spin-spin interaction is already included in the eff... Modified Theories of Gravity include spin dependence in General Relativity, to account for additional sources of gravity instead of dark matter/energy approach. The spin-spin interaction is already included in the effective nuclear force potential, and theoretical considerations and experimental evidence hint to the hypothesis that Gravity originates from such an interaction, under an averaging process over spin directions. This invites to continue the line of theory initiated by Einstein and Cartan, based on tetrads and spin effects modeled by connections with torsion. As a first step in this direction, the article considers a new modified Coulomb/Newton Law accounting for the spin-spin interaction. The physical potential is geometrized through specific affine connections and specific semi-Riemannian metrics, canonically associated to it, acting on a manifold or at the level of its tangent bundle. Freely falling particles in these “toy Universes” are determined, showing an interesting behavior and unexpected patterns. 展开更多
关键词 Modified Gravity Theory SPIN Coulomb’s Law Newton’s Law Modified Coulomb’s Law Nuclear Force adapted Connection adapted Metric
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基于自适应尺度因子的Retinex红外图像增强算法 被引量:8
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作者 郝宇 王新赛 +3 位作者 张彦波 路建方 贺菁 刘雨 《红外技术》 CSCD 北大核心 2016年第10期855-859,共5页
通过总结红外图像增强算法应该具有的基本特征,在分析了基于Retinex理论的图像增强算法中的尺度因子的作用后,提出了基于自适应尺度因子的Retinex红外图像增强算法,不仅改善了红外图像的整体效果,还使动态范围压缩与细节增强的效果达到... 通过总结红外图像增强算法应该具有的基本特征,在分析了基于Retinex理论的图像增强算法中的尺度因子的作用后,提出了基于自适应尺度因子的Retinex红外图像增强算法,不仅改善了红外图像的整体效果,还使动态范围压缩与细节增强的效果达到最优。在仿真验证实验中,不论从主观评测还是统计数据上,该方法都被证明了有效性。 展开更多
关键词 红外图像增强 多尺度因子 自适应 RETINEX理论
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被改写的他者形象——从马德琳形象看贝娄的男性霸权话语 被引量:5
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作者 汪汉利 《齐齐哈尔大学学报(哲学社会科学版)》 2006年第4期78-80,共3页
《赫索格》是索尔.贝娄的代表性作品。在描述马德琳形象时,作家通过男主人公将自己的思想情感与价值取向强加在女主人公身上,致使马德琳成了一个与“我”相对立的他者形象。贝娄运用描述者掌控的话语权力,不仅遮蔽了马德琳的真实面目,... 《赫索格》是索尔.贝娄的代表性作品。在描述马德琳形象时,作家通过男主人公将自己的思想情感与价值取向强加在女主人公身上,致使马德琳成了一个与“我”相对立的他者形象。贝娄运用描述者掌控的话语权力,不仅遮蔽了马德琳的真实面目,还对其形象进行别有用心的歪曲与改写。贝娄对“他者”马德琳的态度,客观上反映了作家的自我中心意识与男性沙文主义思想。 展开更多
关键词 他者 被改写 男性霸权话语
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图像平滑与边缘检测的迭代算法 被引量:3
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作者 任保刚 贾海波 芮杰 《测绘学院学报》 北大核心 2005年第3期178-180,共3页
图像平滑和边缘检测是图像处理、计算机视觉等领域研究的经典问题。区别以往对这两个问题独立求解的做法,文中作者将图像平滑与边缘检测问题结合起来综合考虑。首先,提出了基于全局边缘特征的边缘检测算法并对自适应平滑算法进行了改进... 图像平滑和边缘检测是图像处理、计算机视觉等领域研究的经典问题。区别以往对这两个问题独立求解的做法,文中作者将图像平滑与边缘检测问题结合起来综合考虑。首先,提出了基于全局边缘特征的边缘检测算法并对自适应平滑算法进行了改进。然后,利用迭代处理的思想对图像进行平滑和边缘检测,得到了迭代的平滑与边缘检测算法。实验表明,该算法可以有效地解决平滑过程中的细节保持和边缘检测时剔除伪边缘这两个难题。 展开更多
关键词 平滑 边缘检测 自适应 迭代
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MEMS-actuated metasurface Alvarez lens 被引量:8
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作者 Zheyi Han Shane Colburn +1 位作者 Arka Majumdar Karl F.Bohringer 《Microsystems & Nanoengineering》 EI CSCD 2020年第1期334-344,共11页
Miniature lenses with a tunable focus are essential components for many modern applications involving compact optical systems.While several tunable lenses have been reported with various tuning mechanisms,they often f... Miniature lenses with a tunable focus are essential components for many modern applications involving compact optical systems.While several tunable lenses have been reported with various tuning mechanisms,they often face challenges with respect to power consumption,tuning speed,fabrication cost,or production scalability.In this work,we have adapted the mechanism of an Alvarez lens–a varifocal composite lens in which lateral shifts of two optical elements with cubic phase surfaces give rise to a change in the optical power–to construct a miniature,microelectromechanical system(MEMS)-actuated metasurface Alvarez lens.Implementation based on an electrostatic MEMS generates fast and controllable actuation with low power consumption.The utilization of metasurfaces–ultrathin and subwavelength-patterned diffractive optics–as optical elements greatly reduces the device volume compared to systems using conventional freeform lenses.The entire MEMS Alvarez metalens is fully compatible with modern semiconductor fabrication technologies,granting it the potential to be mass-produced at a low unit cost.In the reported prototype operating at 1550 nm wavelength,a total uniaxial displacement of 6.3µm was achieved in the Alvarez metalens with a direct-current(DC)voltage application up to 20V,which modulated the focal position within a total tuning range of 68µm,producing more than an order of magnitude change in the focal length and a 1460-diopter change in the optical power.The MEMS Alvarez metalens has a robust design that can potentially generate a much larger tuning range without substantially increasing the device volume or energy consumption,making it desirable for a wide range of imaging and display applications. 展开更多
关键词 ELECTROSTATIC OPTICS adapted
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Smoother and Bayesian filter based semi-codeless tracking of dual-frequency GPS signals 被引量:5
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作者 LIAO Bingyu YUAN Hong LIN Baojun 《Science in China(Series F)》 2006年第4期533-544,共12页
To precisely determine the integrated orbit of the Chinese manned spacecraft mission, a smoother and Bayesian filter based technique for optimum semi-codeless tracking of the P(Y) code on dual-frequency GPS signals ... To precisely determine the integrated orbit of the Chinese manned spacecraft mission, a smoother and Bayesian filter based technique for optimum semi-codeless tracking of the P(Y) code on dual-frequency GPS signals has been advanced. This signal processing technique has been proven effective and robust for affording access to dual-frequency GPS signals. This paper introduces the signal dynamics and measurement models, describes the W o D bit estimation method, and corrects the mistakes of direct estimation of W bit in current semi-codeless tracking. Median filter is chosen as a smoother to find the best measurements at the current time among the history and current information. The Bayesian filter is used to track the L2 P(Y) code phase and L2 carrier phase recursively. 展开更多
关键词 GPS P(Y) code W code A/S technology adapted median filter Bayesian filter.
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On the origin of SARS-CoV-2——The blind watchmaker argument 被引量:7
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作者 Chung-I Wu Haijun Wen +19 位作者 Jian Lu Xiao-dong Su Alice CHughes Weiwei Zhai Chen Chen Hua Chen Mingkun Li Shuhui Song Zhaohui Qian Qihui Wang Bingjie Chen Zixiao Guo Yongsen Ruan Xuemei Lu Fuwen Wei Li Jin Le Kang Yongbiao Xue Guoping Zhao Ya-Ping Zhang 《Science China(Life Sciences)》 SCIE CAS CSCD 2021年第9期1560-1563,共4页
In the comparison with SARS-CoVof 2003,SARS-CoV-2 is extremely well adapted to the human populations and its adaptive shift from the animal host to humans must have been even more extensive.By the blind watchmaker arg... In the comparison with SARS-CoVof 2003,SARS-CoV-2 is extremely well adapted to the human populations and its adaptive shift from the animal host to humans must have been even more extensive.By the blind watchmaker argument,such an adaptive shift can only happen prior to the onset of the current pandemic and with the aid of step-by-step selection. 展开更多
关键词 ARGUMENT ORIGIN adapted
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Existence and uniqueness for BSDE with stopping time 被引量:4
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作者 CHEN Zengjing Department of Mathematics, Shandong University, Jinan 250100, China 《Chinese Science Bulletin》 SCIE EI CAS 1998年第2期96-99,共4页
The existence and uniqueness of the solutions for a class of backward stochastic differential equations (BSDEs for short) in a random interval are discussed.
关键词 BSDE STOPPING TIME adapted solution.
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Prevalence and dietetic management of mild gastrointestinal disorders in milk-fed infants 被引量:6
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作者 D Infante Pina X Badia Llach +1 位作者 B Ario-Armengol V Villegas Iglesias 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第2期248-254,共7页
AIM: To assess the prevalence of mild gastrointestinal disorders in milk-fed infants in paediatric practice, and to evaluate the effectiveness and satisfaction with dietetic treatment.METHODS: A cross-sectional epidem... AIM: To assess the prevalence of mild gastrointestinal disorders in milk-fed infants in paediatric practice, and to evaluate the effectiveness and satisfaction with dietetic treatment.METHODS: A cross-sectional epidemiological study was first carried out. A total of 285 paediatricians included 3487 children seen during a period of one week. In a second phase an observational, prospective and multicentre study was conducted and 2069 milk-fed infants with mild gastrointestinal disorders (colic, constipation, regurgitation and diarrhoea) were included. There was a baseline visit (start of treatment) and a final visit four weeks later. The effectiveness of the various Novalac formulas, as well as the satisfaction of the parents/tutors and paediatricians with the dietetic treatment were assessed at the final visit.RESULTS: The prevalence of mild gastrointestinal disorders was 27.8% of all paediatrician consultations (9.2%, 7.8%, 6.1% and 4.6% in relation to colic, constipation, regurgitation and diarrhoea, respectively). The several Novalac adapted milk formulas resolved 88.4% of the mild gastrointestinal disorders. Depending on the type of disorder, differences in response rate were observed. The highest effectiveness was recorded with respect to diarrhoea (92.6%), followed by constipation (91.6%), colic (87.6%) and regurgitation (81%). Overall, 91% of the paediatricians and 88.8% of the parents/tutors were satisfied or very satisfied with the Novalac adapted milk formulas.CONCLUSION: Mild gastrointestinal disorders show a high prevalence in paediatric practice. The Novalac adapted milk formulas have been shown to be effective in treating mild gastrointestinal disorders in milk-fed infants in the context of routine clinical practice. 展开更多
关键词 Mild gastrointestinal disorders PREVALENCE adapted infant formulas Effectiveness SATISFACTION
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Tales of Her
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作者 Zheng Yiwen 《The World of Chinese》 2024年第3期90-93,共4页
Hong Kong novelist Yi Shu’s works are being adapted for movie and TV,but not everyone is sold on the messaging of these female-centric stories.Under a brilliant autumn sky,Huang Yimei glides down the open road.A blac... Hong Kong novelist Yi Shu’s works are being adapted for movie and TV,but not everyone is sold on the messaging of these female-centric stories.Under a brilliant autumn sky,Huang Yimei glides down the open road.A black leather jacket clings to her form.Her motorcycle hums with power.As she rides,the yellow leaves of the trees lining the street blur into a golden haze.“From now on,the world points wherever I want to go,and I embrace my being,fully and utterly,”she says. 展开更多
关键词 YELLOW EVERYONE adapted
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Osteocyte Egln1/Phd2 links oxygen sensing and biomineralization via FGF23 被引量:2
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作者 Megan L.Noonan Pu Ni +15 位作者 Emmanuel Solis Yamil G.Marambio Rafiou Agoro Xiaona Chu Yue Wang Hongyu Gao Xiaoling Xuei Erica L.Clinkenbeard Guanglong Jiang Sheng Liu Steve Stegen Geert Carmeliet William R.Thompson Yunlong Liu Jun Wan Kenneth E.White 《Bone Research》 SCIE CAS CSCD 2023年第1期178-192,共15页
Osteocytes act within a hypoxic environment to control key steps in bone formation.FGF23,a critical phosphate-regulating hormone,is stimulated by low oxygen/iron in acute and chronic diseases,however the molecular mec... Osteocytes act within a hypoxic environment to control key steps in bone formation.FGF23,a critical phosphate-regulating hormone,is stimulated by low oxygen/iron in acute and chronic diseases,however the molecular mechanisms directing this process remain unclear.Our goal was to identify the osteocyte factors responsible for FGF23 production driven by changes in oxygen/iron utilization.Hypoxia-inducible factor-prolyl hydroxylase inhibitors(HIF-PHI)which stabilize HIF transcription factors,increased Fgf23 in normal mice,as well as in osteocyte-like cells;in mice with conditional osteocyte Fgf23 deletion,circulating i FGF23 was suppressed.An inducible MSC cell line(‘MPC2’)underwent FG-4592 treatment and ATACseq/RNAseq,and demonstrated that differentiated osteocytes significantly increased HIF genomic accessibility versus progenitor cells.Integrative genomics also revealed increased prolyl hydroxylase Egln1(Phd2)chromatin accessibility and expression,which was positively associated with osteocyte differentiation.In mice with chronic kidney disease(CKD),Phd1-3 enzymes were suppressed,consistent with FGF23 upregulation in this model.Conditional loss of Phd2 from osteocytes in vivo resulted in upregulated Fgf23,in line with our findings that the MPC2 cell line lacking Phd2(CRISPR Phd2-KO cells)constitutively activated Fgf23 that was abolished by HIF1αblockade.In vitro,Phd2-KO cells lost iron-mediated suppression of Fgf23 and this activity was not compensated for by Phd1 or-3.In sum,osteocytes become adapted to oxygen/iron sensing during differentiation and are directly sensitive to bioavailable iron.Further,Phd2 is a critical mediator of osteocyte FGF23 production,thus our collective studies may provide new therapeutic targets for skeletal diseases involving disturbed oxygen/iron sensing. 展开更多
关键词 FGF23 COLLECTIVE adapted
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Cat Prince
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作者 Xiao Yunfeng 《China Book International》 2024年第1期111-113,共3页
The novel narrates a captivating and imaginative story of"self-discovery and self-acceptance."Through the adventures shared by Xiao Yu and the Cat Prince,they develop profound reflections on their respective... The novel narrates a captivating and imaginative story of"self-discovery and self-acceptance."Through the adventures shared by Xiao Yu and the Cat Prince,they develop profound reflections on their respective lives,conquering fears and embracing life's imperfections,approaching each new day with a broader perspective.The work received the Eighth Good Shanghai Children's Book Award,and the adapted screenplay was nominated for the Golden Character Award by the Beijing Film Academy. 展开更多
关键词 APPROACHING GOLDEN adapted
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Affine Connections and Gauss-Bonnet Theorems in the Heisenberg Group
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作者 WANG Yong 《数学进展》 CSCD 北大核心 2024年第5期1103-1119,共17页
In this paper,we compute sub-Riemannian limits of Gaussian curvature associated to two kinds of Schouten-Van Kampen affine connections and the adapted connection for a Euclidean C2-smooth surface in the Heisenberg gro... In this paper,we compute sub-Riemannian limits of Gaussian curvature associated to two kinds of Schouten-Van Kampen affine connections and the adapted connection for a Euclidean C2-smooth surface in the Heisenberg group away from characteristic points and signed geodesic curvature associated to two kinds of Schouten-Van Kampen affine connections and the adapted connection for Euclidean C2-smooth curves on surfaces.We get Gauss-Bonnet theorems associated to two kinds of Schouten-Van Kampen affine connections in the Heisenberg group. 展开更多
关键词 Schouten-Van Kampen affine connection the adapted connection Gauss-Bonnet theorem sub-Riemannian limit Heisenberg group
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Whole-genome sequencing reveals selection signals among Chinese,Pakistani,and Nepalese goats 被引量:2
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作者 Yefang Li Ying Gong +7 位作者 Zhengkai Zhang Ling Li Xuexue Liu Xiaohong He Qianjun Zhao Yabin Pu Yuehui Ma Lin Jiang 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2023年第5期362-365,共4页
The goat(Capra hircus)is one of the oldest domesticated animal species,with archeological evidence indicating that its earliest domestication from the wild ancestor(bezoar)occurred in the Fertile Crescent 10,000 calib... The goat(Capra hircus)is one of the oldest domesticated animal species,with archeological evidence indicating that its earliest domestication from the wild ancestor(bezoar)occurred in the Fertile Crescent 10,000 calibrated calendar years ago(Zeder and Hesse,2000).A variety of well-adapted goat breeds with excellent economic traits have been selected artificially and naturally for human needs in China,Pakistan,and Nepal.For example,cashmere goat breeds produce fine cashmere wool and are mainly distributed on the Himalayan Plateau(e.g.,Nepal and Tibet)and in cold northern China(e.g.,Inner Mongolia and Liaoning).The Toggenburg dairy goat is the most productive breed of dairy goat and is distributed in at least 50 countries on all continents(Ferro et al.,2017).Pakistani ewes are reared mostly for meat and wool purposes,but some are used as dairy goats,such as the Bugi Toori goat and Pateri goat(Bilal et al.,2018).Additionally,indigenous goats of the southern Asian regions are well adapted to the local hot environment.Their unique traits and biodiversity serve as genetic resources that can be used for the artificial breeding of goats.Recently,several studies have provided patterns of genome-wide characteristics in goat populations to explore the underlying genetic basis of trait formation and environmental adaptability in China(Zhang et al.,2018),Pakistan(Kumar et al.,2018),and Nepal(Sasazaki et al.,2021),respectively.However,due to the proximity of these geographic regions,the profiles of genetic differences,gene flow,and common genes related to high trait performance between goat populations from China,Pakistan,and Nepal remain unclear. 展开更多
关键词 BREEDING adapted WHOLE
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Preliminary Results of Dementia Prevalence among Elderly People at Home by Cognitive Disorder Adapted Test of Niamey (Niger)
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作者 Abdoulkader Andia Maman Sani Bako +5 位作者 Maiga Zara Garba Kané Karima R. Saïdou Daou Mamane Brah Souleymane Eric Adehossi 《Open Journal of Internal Medicine》 2023年第4期471-480,共10页
Introduction: Neurocognitive disorders are frequent with aging and are often seen at advancing stages in our context. It is really difficult to evaluate rapidly Nigerien elderly persons according to tools available on... Introduction: Neurocognitive disorders are frequent with aging and are often seen at advancing stages in our context. It is really difficult to evaluate rapidly Nigerien elderly persons according to tools available on cognitive status while there is a great number of uneducated elderly people who suffer from cognitive deficiency. The purpose was to determine neurocognitive disorders prevalence in uneducated groups and Muslim elderly people by using the cognitive disorder examination (Codex) test adopted in the population living at home in Niamey (Niger). Materials and Methods: These are the results of a preliminary prospective study with simple three (3) random sampling concerning elderly people aged 60 and over living at home in whom the codex test adapted to Niamey was administered in uneducated Muslim elderly people for a total duration of four (4) minutes. This screen-adapted test should be completed by the mini-mental test of Senegal which is adapted globally to uneducated people in hospitals. The basic Codex test was developed in France for educated people, so we used this basic test in our educated people in the same study. Results: A total of 198 patients had been collected, of which 51.5% were female with an average age of 68 years with extremes of 60 to 84 years. 40 were educated. Among educated persons, 62.5% had a very low probability of dementia and 5% had a very high probability of dementia in the first step of the Codex. In the second step, 12.5% had a low probability of dementia and 20% had a high probability in the same group, while 51.3% had a very low probability of dementia and 21.3% had a very high probability of dementia in the first step of CODEX in uneducated elderly. In the second step in the same group, 12.6% had a low probability and 14.5% had a high probability of dementia. Conclusion: The adapted codex test of Niamey is simple and could be rapidly used to screen dementia among uneducated elderly Muslim prayers, and then could confirm it by complementary cognitive status test validated 展开更多
关键词 DEMENTIA ELDERLY adapted Codex of Niamey PREVALENCE NIGER
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A Finite Difference Scheme on a Priori Adapted Meshes for a Singularly Perturbed Parabolic Convection-Diffusion Equation 被引量:4
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作者 Grigory I.Shishkin 《Numerical Mathematics(Theory,Methods and Applications)》 SCIE 2008年第2期214-234,共21页
A boundary value problem is considered for a singularly perturbed parabolic convection-diffusion equation; we construct a finite difference scheme on α priori (sequentially) adapted meshes and study its convergence... A boundary value problem is considered for a singularly perturbed parabolic convection-diffusion equation; we construct a finite difference scheme on α priori (sequentially) adapted meshes and study its convergence. The scheme on α priori adapted meshes is constructed using a majorant function for the singular component of the discrete solution, which allows us to find α priori a subdomain where the computed solution requires a further improvement. This subdomain is defined by the perturbation parameter ε, the step-size of a uniform mesh in χ, and also by the required accuracy of the discrete solution and the prescribed number of refinement iterations K for improving the solution. To solve the discrete problems aimed at the improvement of the solution, we use uniform meshes on the subdomains. The error of the numerical solution depends weakly on the parameter ε. The scheme converges almost ε-uniformly, precisely, under the condition N^-1 = o (ε^v), where N denotes the number of nodes in the spatial mesh, and the value v = v(K) can be chosen arbitrarily small for suitable K. 展开更多
关键词 Singular perturbations convection-diffusion problem piecewise-uniform mesh α priori adapted mesh almost ε-uniform convergence
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