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Embryo and Endosperm Phytochemicals from Polyembryonic Maize Kernels and Their Relationship with Seed Germination

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Phyton-International journal of Experimental Botany 2022年第5期91卷 929-941页

作者： j.david García-Ortíz Rebeca González-Centeno María Alejandra Torres-Tapia j.A.Ascacio-Valdés joséEspinoza-Velázquez Raúl Rodríguez-Herrera Food Research Department School of ChemistryAutonomous University of CoahuilaSaltillo25280México Plant Breeding Department Universidad Autonoma Agraria Antonio Narro(UAAAN)Saltillo25315México

Because of the growing worldwide demand for maize grain,new alternatives have been sought for breeding of this cereal,e.g.,development of polyembryonic varieties,which agronomic performance could positively impact the grain yield per unit area,and nutritional *** objectives of this study were to(1)determine the phytochemicals present in the embryo and endosperm of grain from maize families with high,low,and null polyembryony frequency,which were planted at different locations,and(2)state the relationship between these compounds and seed *** extracted phytochemicals from corn were identified by *** results showed that the genotype with the highest presence of phytochemicals was the brachytic population with high polyembryony called“BAP”,which also required less water during the germination *** number of phytochemicals in both embryo and endosperm tissues was not related to the sowing location where they came from or the type of *** number of different phytochemicals depended on the grain tissue from where they were *** chemical compounds found in the different maize tissues were related to the development of the plant,either in roots or nibs because these are mainly associated with the lignin synthesis.

关键词： Zea mays L HPLC-MS locations kernels phytochemicals

从高血压到伴有高同型半胱氨酸血症的高血压（英文）

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Science Bulletin 2023年第18期 1975-1977页

作者：范芳芳 j.david Spence 霍勇 Department of Cardiology Peking University First Hospital Institute of Cardiovascular Disease Peking University First Hospital Hypertension Precision Diagnosis and Treatment Research Center Peking University First Hospital Divisions of Neurology and Clinical Pharmacology Western University

Over the last 30 years, the number of people with cardiovascular disease(CVD) has continued to increase globally, with hypertension being the leading risk factor for CVD. The burden of hypertension is especially large in countries and regions undergoing economic development and lifestyle transition. The latest survey data from China show that from 2012 to 2015, the prevalence of hypertension among residents aged ≥18 years was as high as27.9%; that is, one in four adults suffer from hypertension [1].

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Advancement flaps

Plastic and Aesthetic Research 2022年第1期9卷 264-273页

作者： Heather Schopper j.david Kriet Clinton Humphrey Department of Otolaryngology-Head and Neck Surgery University of Kansas Medical CenterKansas CityKS 66160USA

Local advancement flaps are a key tool in the armamentarium of the reconstructive *** can be used to repair small and large defects on all areas of the face with excellent skin color and texture match,limited donor site morbidity,and flexibility to hide *** this review,we outline common categories of advancement flaps and discuss common situations for their use.

关键词： Advancement flaps local reconstruction facial cutaneous defects

Kinematic calibration of a class of parallel kinematic machines(PKM) with fewer than six degrees of freedom

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Science China(Technological Sciences) 2003年第5期46卷 515-526页

作者：黄田唐国宝李思维李亚 G.Derek Chetwynd j.david Whitehouse School of Mechanical Engineering Tianjin University Tianjin 300072 China School of Engineering The University of Warwick Coventry CV4 7AL UK

By taking a 3-DOF translational milling machine as an example, this paper investigates the kinematic calibration of PKM systems with fewer than 6-DOF. The error mapping function is formulated in such a way that the geometric errors affecting the compensatable and uncompensatable pose errors can be separated. Based upon the previous investigation, a hierarchical approach to the geometric error identification is proposed. The compensation strategy is developed which is particularly suitable for the PKM systems with translational moving capability. The experiment has been carried out to verify the effectiveness of the proposed approach and the results show that the accuracy can be significantly improved.

关键词： parallel kinematic machines, kinematic calibration, degrees of freedom.

Cyclic load testing of pre-stressed rock anchors for slope stabilization

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journal of Mountain Science 2016年第1期13卷 126-136页

作者： ZHENG Da LIU Fang-zhou jU Neng-pan FROST j.david HUANG Run-qiu State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology School of Civil and Environmental Engineering Georgia Institute of Technology

The objective of this research was to assess the characteristics of seismic induced damage and the deformation patterns of pre-stressed cement-grouted cables that are used for rock slope stabilization projects subjected to quasi-static cyclic *** experimental configuration includes the installation of 15 pre-stressed cables in a slope model made of concrete blocks(theoretically rigid rock mass) on top of a pre-existing sliding *** study showed that:(i) The pre-stressed cables exhibited great seismic *** displacement of the model blocks was observed after the complete loss of the initial pre-stress load under continued applied cyclic loads and exceedance of the state of equilibrium,which implies the higher the initial pre-stress load,the better the seismic performance of the rock anchor;(ii) The failure of the pre-stressed cables was due to fracture at the connection of the tendons and cable heads under cyclic *** sequence of failure had a distinct *** was first observed at the upper row of cables,which experienced the most severe damage,including the ejection of cable *** evidence of de-bonding was observed during the cyclic loading;(iii) The stress distribution of the bond length for pre-stressed cables was highly *** stress concentrations were observed at both the fixed end and the free end of the bond length both before and immediately after the state of equilibrium is *** results obtained can be used to evaluate the overall performance of pre-stressed rock anchors subject to seismic loading and their potential as rockfall prevention and stabilization measures.

关键词：下线服务迁移

Wet Pressing Models to Reduce Energy Consumption in Papermaking

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Paper And Biomaterials 2019年第1期4卷 1-6页

作者： j.david McDonald Richard j.Kerekes joe R.Zhao jDMcD Consulting Inc. Vaudreuil-Dorion Quebec J7V 0G1 Canada Pulp and Paper Centre the University of British Columbia Vancouver BC V6T 1Z4 Canada Tri-Y Environmental Research Institute Vancouver BC V5M 3H9 Canada

Improved wet pressing reduces the need for drying and consequently energy needed in papermaking. Accordingly, it is desirable to optimize wet pressing, but the process is very complex with many interacting variables. It is therefore desirable to employ a mathematical model that accounts for the major variables to estimate the effects of changes in equipment and operating variables. This paper descibes such a model called the Decreasing Permeability Model (DPM). Mill and pilot plant applications over a wide range of basis weights for paper and paper board are described.

关键词： wet pressing Decreasing Permeability Model (DPM) papermaking water removal rewet mathemeitical model

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从高血压到伴有高同型半胱氨酸血症的高血压

科学通报:英文版 2023年第18期68卷 1975-1977页

作者：范芳芳 j.davidSpence 霍勇 Department of Cardiology Peking University First HospitalBeijing 100034China Institute of Cardiovascular Disease Peking University First HospitalBeijing 100034China Hypertension Precision Diagnosis and Treatment Research Center Peking University First HospitalBeijing 100034China Divisions of Neurology and Clinical Pharmacology Western UniversityLondon ON N6G 2V4Canada

Over the last 30 years,the number of people with cardiovascular disease(CVD)has continued to increase globally,with hypertension being the leading risk factor for *** burden of hypertension is especially large in countries and regions undergoing economic development and lifestyle *** latest survey data from China show that from 2012 to 2015,the prevalence of hypertension among residents aged18 years was as high as 27.9%;that is,one in four adults suffer from hypertension[1].It follows that the current prevention and control of hypertension is ***,how best to improve hypertension management to reduce the CVD burden is a major global *** we depict the challenges that cardiologists and neurologist face in the present era of CVD.

关键词： hypertension prevention 高同型半胱氨酸血症

Recent Advances in Stroke Prevention

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中华脑血管病杂志（电子版） 2020年第1期14卷 1-12页

作者： j.david Spence Neurology&Clinical Pharmacology Western University/Stroke Prevention&Atherosclerosis Research CentreRobarts Research Institute

Stroke is the most important cause of death and disability in China,and most strokes(~80-90%)are *** advances in a number of measures to reduce stroke are discussed in this narrative review,including smoking cessation,a Mediterranean pattern of eating,salt restriction,B vitamins to lower homocysteine,antiplatelet therapy,anticoagulants and the management of patent foramen ovale and carotid *** of homocysteine with B vitamins does prevent stroke,but patients with variants of MTHFR require higher doses of folic acid,and because of harm from cyanocobalamin among persons with renal impairment,we should use methylcobalamin or oxocobalamin *** resistance appears to be due to enteric coating,and>50% of Chinese have a reduced response to clopidogrel because of variants of CYP2C19,required to convert the prodrug to its active *** acting oral anticoagulants(DOACs)have revolutionized anticoagulation;important differences among the DOACs are *** closure of patent foramen ovale(PFO)does reduce the risk of stroke,but in most patients with stroke and PFO the PFO is incidental;it is important to identify the subgroup in whom paradoxical embolism was the probable cause of the *** patients with PFO would be better treated with anticoagulants because of the risk of pulmonary *** stenting carries a higher risk in older patients,and most patients with asymptomatic carotid stenosis would be better treated with intensive medical therapy than with either stenting or endarterectomy;the few who could benefit can be identified.

关键词： vitamin doses instead

日常仪式化行为的形成:从雷锋日记到知青日记

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社会 2007年第1期27卷 98-119页

作者：吴艳红 j.david Knottnerus 湖南农业大学人文学院美国俄克拉何马州立大学社会学系

本文关注日常仪式化行为的形成。以知青日记写作为例,本文深入探讨了这一日常仪式化行为形成的过程。因其日常性和表达实践中的个人性,日常仪式化行为的社会性是容易被忽略的。本文主要利用结构仪式化理论,证明日常仪式化行为包含了丰... 详细信息

本文关注日常仪式化行为的形成。以知青日记写作为例,本文深入探讨了这一日常仪式化行为形成的过程。因其日常性和表达实践中的个人性,日常仪式化行为的社会性是容易被忽略的。本文主要利用结构仪式化理论,证明日常仪式化行为包含了丰富的社会内涵和群体存在特征,社会、群体存在特征和个人在日常仪式化行为形成中具有关键的作用。社会领域的公共行为是群体和个人日常仪式化行为的真正来源,群体的存在特征则为群体成员复制、选择、调整甚至改变这些公共行为提供了条件,而对社会公共行为和群体特征的估量则是由个人完成的。

关键词：日常仪式化行为日记知青仪式化