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Genetic Diversity of European and Chinese Oilseed Brassica rapa Cultivars from Different Breeding Periods

Agricultural Sciences in China 2009年第8期8卷 931-938页

作者： ZHAO Yong-guo ofori atta LU Chang-ming Oil Crops Research Institute Chinese Academy of Agricultural Sciences Wuhan 430062 P.R.China Graduate School Chinese Academy of Agricultural Sciences Beijing 100081 P.R. China Department of Crop Sciences Georg-August-University Goettingen Goettingen 37075 Germany

The Brassica oilseed crops went through two major breeding bottlenecks during the introgression of genes for zero erucic acid and low glucosinolate content, respectively, which may lead to reduced genetic biodiversity of the crop. This study investigates the impact of these bottlenecks on the genetic diversity within and across European and Chinese winter B. rapa cultivars. We compared eight cultivars from Europe and China, representing three different seed qualities from three different breeding periods：（1） high erucic acid, high glucosinolates （＋＋）; （2） zero erucic acid, high glucosinolates（0＋）; （3） zero erucic acid, low glucosonolates （00, canola quality）. Diversity was estimated on 32 plants per cultivar, with 16 simple sequence repeat （SSR） markers covering each of the B. rapa linkage groups. The analysis of molecular variance （AMOVA） showed that genetic variations within cultivars, across cultivars and across regions （Europe and China） were significant, with about 60% of the total variation within cultivars. There was a slight, but non-significant loss in genetic diversity within cultivars when comparing the three breeding periods as indicated by effective number of alleles （2.39, 2.23, and 1.99 for breeding periods 1, 2, and 3, respectively）, Shannon information index （0.93, 0.90, 0.75）, and expected heterozygosity （0.51, 0.49, 0.42）. By cluster analysis （UPGMA dendrogram） and principal coordinate analysis, Chinese and European cultivars were clearly divided into two distinct groups. In conclusion, quality improvement did not significantly reduce the genetic diversity of European and Chinese B. rapa cultivars.

关键词： Brassica rapa genetic diversity breeding period simple sequence repeat

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Considering solid shear stress in MP-PIC simulation of a CFB riser

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Particuology 2024年第6期89卷 79-87页

作者： Tagir Kadyrov Fei Li atta Ullah Nature-inspired Engineering Center University of TyumenTyumen 625003Russia Laboratory of Theory and Optimization of Chemical and Technological Processes University of TyumenTyumen625003Russia State Key Laboratory of Multi-phase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China Department of Chemical Engineering Pakistan Institute of Engineering&Applied SciencesIslamabad 45650Pakistan

To enable successful multi-phase particle-in-cell(MP-PIC)simulations of circulating fluidized beds(CFBs),both the interphase drag force and interparticle collisions need to be carefully *** collisions are usually represented by the solid stress consisting of the normal and shear components,in which the normal stress was found to have a leading role in the numerical stability of MP-PIC simulations,whereas the impact of the shear stress has seldom been *** this work,the effects of the solid shear stress are investigated by using two-dimensional simulations of the moderately dense laboratory-scale CFB riser with in-house MP-PIC code implemented on MFIX open-source *** including only normal solid stress and those considering both normal and shear solid stresses are *** results of solids flux,axial and radial solids profiles are compared with available experimental *** results show that the solid shear stress plays a minor role on the accuracy of simulation,and the increase of PPP(number particles per parcel)leads to a lower accuracy of simulation.

关键词： Simulation Fluidization Multiphase particle-in-cell(MP-PIC) Solid shear stress

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Evaluation of Major Chemical Components in Beans of Some Selected International Cocoa Clones in Ghana

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Journal of Agricultural Science and Technology(B) 2014年第3期4卷 200-208页

作者： Abu Mustapha Dadzie Stephen Yaw Opoku atta ofori Samuel Lowor Jemmy Felix Takrama Francis Kwame Padi Julius Yeboah Department of Plant Breeding Cocoa Research Institute of Ghana (CRIG) Tafo-Akim Ghana

Cocoa bean is an important raw material for the chocolate, pharmaceutical and cosmetic industries. The butter content and other chemical components such as polyphenols play essential role in the health benefits of consumers as well as flavor of chocolates produced. In this study cocoa beans from 15 international clones （genotypes） were fermented and dried for six and 14 days, respectively. Genotypic effect on the major chemical components of the beans that affect chocolate flavour and taste were assessed using various protocols in the laboratory. Concentrations and relationship existing among the chemical components tested during three- and two-year periods were determined. Genotypic differences were found to account for variation in the concentration of various components tested. Among the genotypes used Man 15-2 seems to be high in fat content whilst IMC 47 was low. In terms of O-dihydric phenol content ICS 1 recorded the highest whilst MO 20 recorded the least. A further test on polyphenols content showed high levels for Gu 255 whilst T 79/501 recorded the least. Significant positive correlation was also observed among the various chemical components tested. The findings of this work clearly confirmed the existence of significant correlations among the major chemical components in cocoa beans and the influence of genotype on the chemical component concentration. This information could be very useful in breeding and selection for a particular component since genotype plays a major role.

关键词： Cocoa clones polyphenols O-dihydrics.

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Genotypic Effect of Rootstock and Scion on Grafting Success and Growth of Kola (Cola nitida) Seedlings

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American Journal of Plant Sciences 2014年第26期5卷 3873-3879页

作者： Abu Mustapha Dadzie Abraham Akpertey Julius Yeboah Stephen Yaw Opoku atta ofori Samuel Lowor Richard Ackyeampong Patricia Adu- Yeboah Mercy Asamoah Frank Manu Amoah Cocoa Research Institute of Ghana (CRIG) Tafo-Akim Ghana

Kola (Cola nitida) is an important economic cash crop for many West and Central African countries. It has several medicinal uses in the pharmaceutical industries and also plays a major role in traditional marriages among Islamic communities across West and Central Africa. The crop is extensively cultivated in Nigeria and Ghana. However, it exhibit signs of total and partial sterility as well as self incompatibility when propagated from seeds in most cases. Therefore, grafting is seen as a method of choice in addressing the problem stated above. Though grafting accounts for some degree of success, there is the need to assess genotypic and physiological factors that account for high or low grafting success. Genetic and physiological factors (such as rootstock age) affecting grafting success and growth in kola (C. nitida) were investigated in two separate experiments. In experiment I720 kola seedlings were raised from unselected kola nuts and sown at two monthly intervals. Four groups of seedlings (180/group) i.e. 6, 8, 10 and 12 months old were thus produced. Three different scions (A1, A12 and JB1) measuring (5-10 cm) were grafted onto the four age groups of rootstocks, namely, 6, 8, 10 and 12 months. Experiment II consisted of 540 seedlings raised from three main crosses (JX1/9 × JX1/11 * B1/142 × B1/151, JX1/9 × JX1/11 * B2/177 × B2/156 and JX1/9 × JX1/11 * GX1/46 × GX1/53). Grafting was done after six months using the same set of scions as described in experiment I. Experimental design used was 3 × 4 and 3 × 3 factorial designs in completely randomised design with three replicates for experiment I and II respectively. The fixed effects were the different genotype and age of rootstock at grafting whilst the response variable was the percentage of successful grafting two months as well as growth at six monthly intervals. Results from the study showed that grafting onto 6 months old stocks gave the highest percentage success and growth of grafts followed by 8, 10 and

关键词： Kola Rootstock Scion Genotype

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Effectiveness of external prestressing in enhancing the non-ductile hanger failure mechanism in reinforced concrete inverted T-beams

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Frontiers of Structural and Civil Engineering 2024年第7期18卷 1050-1065页

作者： Ahmed M.atta Reda N.BEHIRY Mohammed I.HARAZ Structural Engineering Department Faculty of EngineeringTanta UniversityTanta 33511Egypt Nile Higher Institute for Engineering and Technology Mansoura 11001Egypt

Recently,inverted T-beams have been used in reinforced concrete(RC)bridges to support transverse precast *** T-beams,contrary to practice with conventional beams,are loaded on the flanges upper *** loading configuration causes hanger failure due to the generation of vertical tensile stresses near the bottom of the *** key purpose of this study is to investigate the efficiency of vertical external prestressing stainless-steel bars in mitigating non-ductile hanger failure in reinforced concrete inverted *** experimental study on six inverted-T beams,including two un-strengthened specimens,was carried *** study showed that the value of the prestressing level had a considerable impact on the performance of hanger mechanism in relation to crack pattern,ultimate loads,cracking behavior,load-deflection,strains,and *** experimental results indicated that the suggested method for strengthening inverted T-beams had efficacy in reducing the seriousness of the non-ductile hanger failure and resulted in a strength increase of up to 53% when compared to that of the un-strengthened ***,two analytical models for estimating the hanger capacity and the average crack width of the strengthened RC inverted T-beams were *** models that were proposed exhibited a high degree of agreement with the experimental results.

关键词： RC bridges inverted T-beams strengthening hanger failure external prestressing

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Detection of onset of agglomeration in a bubbling fluidized bed biomass combustor using reactive Eulerian computational fluid dynamics

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Particuology 2024年第7期90卷 504-515页

作者： Abdullah Tasleem atta Ullah Fei Li Qun Yi William Nimmo Syed Sheraz Daood Department of Chemical Engineering Pakistan Institute of Engineering and Applied Sciences(PIEAS)Lehtrar RoadP.O.Nilore45650IslamabadPakistan Institute of Process Engineering Chinese Academy of SciencesBeijing100190China School of Chemical Engineering and Pharmacy Wuhan Institute of TechnologyWuhan430205China Energy Engineering Group Energy 2050Department of Mechanical EngineeringUniversity of SheffieldSheffieldS37RDUnited Kingdom Institute of Energy and Environmental Engineering Faculty of ElectricalEnergy&Environmental EngineeringUniversity of the PunjabQuaid-e-Azam CampusLahorePakistan Energy Engineering Research and Development Centre Faculty of ElectricalEnergy&Environmental EngineeringUniversity of the PunjabQuaid-e-Azam CampusLahorePakistan

The choice of a type of combustion technology to be used for heat or power generation depends on economic,technical,operational and fuel availability *** benefits associated with the evolving market driven by the fluidised bed combustion(FBC)technology cannot be overlooked especially when gauged at 65 GWth of worldwide installed capacity alongside added benefits of handling fuel variation,low pollutant emissions and high combustion *** or biomass waste will continue to have a vital role to play in the future FBC technology-based power *** often contains high levels of inorganic species that can form sticky agglomerates posing a significant risk to boiler operation resulting in unscheduled *** added complexity of the behaviour of the fuel and bed material mix highlights the requirement for simulation models to identify agglomeration to help improve the overall performance and reliability of FBC *** resolve this problem,this research devised a simulation strategy for the detection of agglomeration using the Eulerian–Eulerian *** developed modelling strategy is validated with the experimental data available in literature for two-dimensional simplified geometry of a pilot-scale fluidised bed *** model results were found promising and robust to predict bed defluidisation times and other parameters consistent with the experimental data.

关键词： Fluidized bed combustion Eulerian Models Biomass Agglomeration Defluidisation

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Building a Smart Management System for the Field Training Course at the Faculty of Specific Education-Mansoura University

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Computer Systems Science & Engineering 2024年第5期48卷 1213-1250页

作者： Soha A.Shaban Amira A.atta Dalia L.Elsheweikh Department of Computer Science Faculty of Specific EducationMansoura UniversityMansoura35516Egypt

Field training is the backbone of the teacher-preparation *** importance stems from the goals that colleges of education aim to achieve,which include bridging the gap between theory and practice and aligning with contemporary educational trends during teacher ***,trainee students attendance in field training is recordedmanually through signatures on attendance ***,thismethod is prone to impersonation,time wastage,and ***,traditional methods of evaluating trainee students are often susceptible to human errors during the evaluation and scoring *** training also lacks modern technology that the supervisor can use in case of his absence from school to monitor the trainee students’implementation of the required activities and *** shortcomings do not meet the needs of the digital era that universities are currently *** a result,this paper presents a smart management system for field training based on Internet of Things(IoT)and mobile *** includes three subsystems:attendance,monitoring,and *** attendance subsystem uses an R307 fingerprint sensor to record trainee students’*** Arduino Nano microcontroller transmits attendance data to the proposed Android application via an ESP-12F Wi-Fi module,which then forwards it to the Firebase database for *** monitoring subsystem utilizes Global Positioning System(GPS)technology to continually track trainee students’locations,ensuring they remain at the school during *** also enables remote communication between trainee students and supervisors via audio,video,or text by integrating video call and chat *** evaluation subsystem is based on three items:an online exam,attendance,and implementation of required activities and *** results have demonstrated the accuracy and efficiency of the proposed management system in recording attendance,as well as in monitoring and evaluating

关键词： Field training digital transformation mobile technology GPS video call chat online exam

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Room Temperature Synthesis of Vertically Aligned Amorphous Ultrathin NiCo-LDH Nanosheets Bifunctional Flexible Supercapacitor Electrodes

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Energy & Environmental Materials 2024年第2期7卷 277-286页

作者： Kwadwo Asare Owusu Zhaoyang Wang Ali Saad Felix ofori Boakye Muhammad Asim Mushtaq Muhammad Tahir Ghulam Yasin Dongqing Liu Zhengchun Peng Xingke Cai Institute for Advanced Study Shenzhen UniversityShenzhen 518060China College of Physics and Optoelectronics Shenzhen University3688 Nanhai BoulevardNanshan DistrictShenzhen 518060China School of Chemistry and Materials Science Hubei Engineering UniversityNo.272 Traffic AvenueXiaogan 432000China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyNo.122 Luoshi RoadWuhan 430070China Key Laboratory of Green Printing CAS Research Centre for Excellence in Molecular ScienceInstitute of Chemistry Chinese Academy of Sciences(ICCAS)Beijing 100190China College of Mechatronics and Control Engineering Shenzhen University3688 Nanhai BoulevardNanshan DistrictShenzhen 518050China

Developing a simple scalable method to fabricate electrodes with high capacity and wide voltage range is desired for the real use of electrochemical ***,we synthesized amorphous NiCo-LDH nanosheets vertically aligned on activated carbon cloth substrate,which was in situ transformed from Co-metal-organic framework materials nano-columns by a simple ion exchange process at room *** to the amorphous and vertically aligned ultrathin structure of NiCo-LDH,the NiCo-LDH/activated carbon cloth composites present high areal capacities of 3770 and 1480 mF cm^(-2)as cathode and anode at 2 mA cm^(-2),and 79.5%and 80%capacity have been preserved at 50 mA cm^(-2).In the meantime,they all showed excellent cycling performance with negligible change after>10000 *** fabricating them into an asymmetric supercapacitor,the device achieves high energy densities(5.61 mWh cm^(-2)and 0.352 mW cm^(-3)).This work provides an innovative strategy for simplifying the design of supercapacitors as well as providing a new understanding of improving the rate capabilities/cycling stability of NiCo-LDH materials.

关键词： amorphous nanosheets aqueous supercapacitor high volumetric/areal energy density NiCo-LDH room temperature synthesis

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Diabetic Retinopathy Detection: A Hybrid Intelligent Approach

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Computers, Materials & Continua 2024年第9期80卷 4561-4576页

作者： atta Rahman Mustafa Youldash Ghaida Alshammari Abrar Sebiany Joury Alzayat Manar Alsayed Mona Alqahtani Noor Aljishi Department of Computer Science(CS) College of Computer Science and Information Technology(CCSIT)Imam Abdulrahman Bin Faisal University(IAU)P.O.Box 1982Dammam31441Saudi Arabia Department of Computer Engineering(CE) College of Computer Science and Information Technology(CCSIT)Imam Abdulrahman Bin Faisal University(IAU)P.O.Box 1982Dammam31441Saudi Arabia

Diabetes is a serious health condition that can cause several issues in human body organs such as the heart and kidney as well as a serious eye disease called diabetic retinopathy(DR).Early detection and treatment are crucial to prevent complete blindness or partial vision *** detection methods,which involve ophthalmologists examining retinal fundus images,are subjective,expensive,and ***,this study employs artificial intelligence(AI)technology to perform faster and more accurate binary classifications and determine the presence of *** this regard,we employed three promising machine learning models namely,support vector machine(SVM),k-nearest neighbors(KNN),and Histogram Gradient Boosting(HGB),after carefully selecting features using transfer learning on the fundus images of the Asia Pacific Tele-Ophthalmology Society(APTOS)(a standard dataset),which includes 3662 images and originally categorized DR into five levels,now simplified to a binary format:No DR and DR(Classes 1-4).The results demonstrate that the SVM model outperformed the other approaches in the literature with the same dataset,achieving an excellent accuracy of 96.9%,compared to 95.6%for both the KNN and HGB *** approach is evaluated by medical health professionals and offers a valuable pathway for the early detection of DR and can be successfully employed as a clinical decision support system.

关键词： Diabetic retinopathy transfer learning machine learning fundus images binary classification APTOS

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Straw return influences the structure and functioning of arbuscular mycorrhizal fungal community in a rice-wheat rotation system

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Pedosphere 2024年第2期34卷 339-350页

作者： Silong ZHAI Junjie XIE Zongyi TONG Bing YANG Weiping CHEN Roger TKOIDE Yali MENG Xiaomin HUANG atta Mohi Ud DIN Changqing CHEN Haishui YANG College of Agriculture Nanjing Agricultural UniversityNanjing 210095China Department of Biology Brigham Young UniversityProvo UT 84602USA Jiangsu Key Laboratory of Crop Genetics and Physiology/Jiangsu Key Laboratory of Crop Cultivation and Physiology Agricultural College of Yangzhou UniversityYangzhou 225009China National Research Center of Intercropping The Islamia University of BahawalpurBahawalpur 63100Pakistan Jiangsu Collaborative Innovation Center for Modern Crop Production Nanjing Agricultural UniversityNanjing 210095China

Straw return is a sustainable soil fertility-building practice,which can affect soil microbial ***,how straw return affects arbuscular mycorrhizal fungi(AMF)is not well ***,we studied the impacts of different straw management treatments over eight years on the structure and functioning of AMF communities in a rice-wheat rotation *** straw management treatments included no tillage with no straw(NTNS),rotary tillage straw return(RTSR),and ditch-buried straw return(DBSR).The community structure of AMF was characterized using high-throughput sequencing,and the mycorrhizal functioning was quantified using an in situ mycorrhizal-suppression *** straw management treatments formed unique AMF community structure,which was closely related to changes in soil total organic carbon,available phosphorus,total nitrogen,ammonium,and *** compared with NTNS,RTSR significantly increased Shannon diversity in 0–10 cm soil layer,while DBSR increased it in 10–20 cm soil layer;DBSR significantly increased hyphal length density in the whole ploughing layer(0–20 cm),but RTSR only increased it in the subsurface soil layer(10–20 cm).The mycorrhizal responses of shoot biomass and nutrient(N and P)uptake were positive under both straw return treatments(RTSR and DBSR),but negative under *** community composition of AMF was significantly correlated to hyphal length density,and the latter was further a positive predictor for the mycorrhizal responses of plant growth and nutrient *** findings suggest that straw return can affect AMF community structure and functioning,and farmers should manage mycorrhizas to strengthen their beneficial effects on crop production.

关键词： community structure hyphal length density shoot biomass shoot N uptake shoot P uptake soil physicochemical properties straw management tillage

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