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multichannel imaging for monitoring chemical composition and germination capacity of cowpea(Vigna unguiculata) seeds during development and maturation

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The Crop Journal 2022年第5期10卷 1399-1411页

作者： Gamal Elmasry nasser mandour Yahya Ejeez Didier Demilly Salim.al-Rejaie Jerome Verdier Etienne Belin David Rousseau Agricultural Engineering Department Faculty of AgricultureSuez Canal UniversityIsmailiaEgypt Groupe d’Etude et de Controle des Variétés et des Semences(GEVES) Station Nationale d’Essais de Semences(SNES)Beaucouze49071AngersFrance Department of Pharmacology&Toxicology College of PharmacyKing Saud UniversitySaudi Arabia Laboratoire Angevin de Recherche en Ingenierie des Systemes(LARIS) Universited’AngersAngersFrance Institut National de la Recherche Agronomique(INRA) UMR1345 Institut de Recherche en Horticulture et SemencesBeaucouzéF-49071AngersFrance

This study aimed to set a computer-integrated multichannel spectral imaging system as a high-throughput phenotyping tool for the analysis of individual cowpea seeds harvested at different developmental stages. The changes in germination capacity and variations in moisture, protein and different sugars during twelve stages of seed development from 10 to 32 days after anthesis were nondestructively monitored. multispectral data at 20 discrete wavelengths in the ultraviolet, visible and near infrared regions were extracted from individual seeds and then modelled using partial least squares regression and linear discriminant analysis(LDA) models. The developed multivariate models were accurate enough for monitoring all possible changes occurred in moisture, protein and sugar contents with coefficients of determination in prediction R^(2) of 0.93, 0.80 and 0.78 and root mean square errors in prediction(RmSEP) of 6.045%, 2.236% and 0.890%, respectively. The accuracy of PLS models in predicting individual sugars such as verbascose and stachyose was reasonable with R~2 of 0.87 and 0.87 and RmSEP of 0.071%and 0.485%, respectively;but for the prediction of sucrose and raffinose the accuracy was relatively limited with R^(2) of 0.24 and 0.66 and RmSEP of 0.567% and 0.045%, respectively. The developed LDA model was robust in classifying the seeds based on their germination capacity with overall correct classification of96.33% and 95.67% in the training and validation datasets, respectively. With these levels of accuracy,the proposed multichannel spectral imaging system designed for single seeds could be an effective choice as a rapid screening and non-destructive technique for identifying the ideal harvesting time of cowpea seeds based on their chemical composition and germination capacity. moreover, the development of chemical images of the major constituents along with classification images confirmed the usefulness of the proposed technique as a non-destructive tool for estim

关键词： multispectral imaging multichannel imaging Chemical imaging Spectral analysis Seeds Cowpea

Real-time-guided bone regeneration around standardized critical size calvarial defects using bone marrow-derived mesenchymal stem cells and collagen membrane with and without using tricalcium phosphate: an in vivo microcomputed tomographic and histologic e

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International Journal of Oral Science 2016年第1期8卷 7-15页

作者： Khalid al-Hezaimi Sundar Ramalingam mansour al-Askar Aws S ArRejaie nasser Nooh Fawad Jawad Abdullah aldahmash muhammad Atteya Cun-Yu Wang Engineer A.B.Growth Factors and Bone Regeneration Research Chair and 3D Imaging Center College of DentistryKing Saud UniversityRiyadhSaudi Arabia Department of Periodontics and Community Dentistry College of DentistryKing Saud UniversityRiyadhSaudi Arabia Department of Oral and maxillofacial Surgery College of DentistryKing Saud UniversityRiyadhSaudi Arabia Department of Substitutive Dental Sciences College of DentistryUniversity of DammamDammamSaudi Arabia Stem Cell Unit Department of AnatomyCollege of MedicineKing Saud UniversityRiyadh Division of Oral Biology and medicine School of DentistryUniversity of California at Los AngelesLos AngelesUSA

The aim of the present real time in vivo micro-computed tomography （pCT） and histologic experiment was to assess the efficacy of guided bone regeneration （GBR） around standardized calvarial critical size defects （CSD） using bone marrow-derived mesenchymal stem cells （BmSCs）, and collagen membrane （Cm） with and without tricalcium phosphate （TCP） graft material. In the calvaria of nine female Sprague-Dawley rats, full-thickness CSD （diameter 4.6 mm） were created under general anesthesia. Treatment-wise, rats were divided into three groups. In group 1, CSD was covered with a resorbable Cm; in group 2, BmSCs were filled in CSD and covered with Cm; and in group 3, TCP soaked in BmSCs was placed in CSD and covered with Cm. all defects were closed using resorbable sutures. Bone volume and bone mineral density of newly formed bone （NFB） and remaining TCP particles and rate of new bone formation was determined at baseline, 2, 4, 6, and 10 weeks using in vivo pCT. At the lOth week, the rats were killed and calvarial segments were assessed histologically. The results showed that the hardness of NFB was similar to that of the native bone in groups I and 2 as compared to the NFB in group 3. Likewise, values for the modulus of elasticity were also significantly higher in group 3 compared to groups 1 and 2. This suggests that TCP when used in combination with BmSCs and without Cm was unable to form bone of significant strength that could possibly provide mechanical ＂lock＂ between the natural bone and NFB. The use of BmSCs as adjuncts to conventional GBR initiated new bone formation as early as 2 weeks of treatment compared to when GBR is attempted without adiunct BmSC therapy.

关键词： bone marrow-derived mesenchymal stem collagen membrane critical size defect guided bone regeneration tricalciumphosphate

A stochastic based approach for a new site classification method:application to the algerian seismic code

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Earthquake Engineering and Engineering Vibration 2015年第4期14卷 663-681页

作者： mohamed Beneldjouzi nasser Laouami Civil Engineering Faculty University of Sciences and Technology Houari Boumediene Earthquake Engineering Applied Research Center (CGS)

Building codes have widely considered the shear wave velocity to make a reliable subsoil seismic classification, based on the knowledge of the mechanical properties of material deposits down to bedrock. This approach has limitations because geophysical data are often very expensive to obtain. Recently, other alternatives have been proposed based on measurements of background noise and estimation of the H/V amplification curve. However, the use of this technique needs a regulatory framework before it can become a realistic site classification procedure. This paper proposes a new formulation for characterizing design sites in accordance with the algerian seismic building code (RPA99/ver.2003), through transfer functions, by following a stochastic approach combined to a statistical study. For each soil type, the deterministic calculation of the average transfer function is performed over a wide sample of 1-D soil profiles, where the average shear wave (S-W) velocity, Vs, in soil layers is simulated using random field theory. Average transfer functions are also used to calculate average site factors and normalized acceleration response spectra to highlight the amplification potential of each site type, since frequency content of the transfer function is significantly similar to that of the H/V amplification curve. Comparison is done with the RPA99/ver.2003 and Eurocode8 (EC8) design response spectra, respectively. In the absence of geophysical data, the proposed classification approach together with micro-tremor measures can be used toward a better soil classification.

关键词： random field transfer function soil classification RPA99/ ver. 2003 EC8 site factor response spectrum

Hierarchical TiO_2/ZnO Nanostructure as Novel Non-precious Electrocatalyst for Ethanol Electrooxidation

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Journal of materials Science & Technology 2015年第1期31卷 97-105页

作者： Gehan m.K.Tolba nasser A.m.Barakat A.m.Bastaweesy E.A.Ashour Wael Abdelmoez mohamed H.El-Newehy Salem S.al-Deyab Hak Yong Kim Organic materials and Fiber Engineering Department Chonbuk National University Chemical Engineering Department Faculty of EngineeringMinia University BioNanosystem Department Chonbuk National University Department of Chemistry College of ScienceKing Saud University

metal oxides have a higher chemical stability in comparison to metals,so they can be utilized as electrocatalysts if the activity could be *** the composition,the morphology of the nanostructures has a considerable impact on the electrocatalytic *** this work,zinc oxide nano branches-attached titanium dioxide nanofibers were investigated as an economic and stable catalyst for ethanol electrooxidation in the alkaline *** introduced material has been synthesized by electrospinning process followed by hydrothermal ***,electrospinning of colloidal solution consisting of titanium isopropoxide,poly（vinyl acetate） and zinc nanoparticles was performed to produce nanofibers embedding solid *** order to produce TiO2nanofibers containing ZnO nanoparticles,the obtained electrospun nanofiber mats were calcined in air at 600 °*** formed ZnO nanoparticles were exploited as seeds to outgrow ZnO branches around the TiO2nanofibers using the hydrothermal technique at sub-critical water conditions in the presence of zinc nitrate and bis-hexamethylene *** morphology of the final product,as well as the electrochemical measurements indicated that zinc nanoparticles content in the original electrospun nanofibers has a significant influence on the electrocatalytic activity as the best performance was observed with the nanofibers synthesized from electrospun solution containing 0.1 g Zn,and the corresponding current density was 37 mA/***,this study paves a way to titanium dioxide to be exploited to synthesize effective and stable metal oxide-based electrocatalysts.

关键词： Direct ethanol fuel cells Electrospinning Nanofibe

Effect of the degree of template removal from mesoporous silicate materials on their adsorption of heavy oil from aqueous solution

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Frontiers of Chemical Science and Engineering 2014年第4期8卷 488-497页

作者： Farouq TWAIQ m.S. nasser Sagheer A. ONAIZI Faculty of Engineering Computing and Science Swinbume University of Technology Kuching 93350 Malaysia Gas Processing Center College of Engineering Qatar University Doha P. O. Box 2713 Qatar School of Chemical Engineering and Advanced materials Newcastle University Singapore 599489 Singapore School of Chemical Engineering and Advanced materials Newcastle University Newcastle upon Tyne NE1 7RU UK

The key aim of this study is to evaluate the adsorption of heavy oil from aqueous solutions with different oil contents over mesoporous silicate materials having different surfactant template contents. The meso- porous silicate materials have been synthesized from tetraethylorthosilicate as a silica precursor and cetyltri- methylammonium bromide as a template using the sol-gel technique. Four samples were prepared by （1） totally removing the template using the calcination process, （2） partially removing the template via ethanol extraction, （3） partially removing the template via water extraction, and （4） keeping the template as synthesized, respectively. These four samples have been characterized using X-ray diffraction, nitrogen adsorption, thermal gravimetric ana- lysis and Fourier transformed infrared. The effect of the degree of template removal of these mesoporous materials for the oil removal has been investigated. The oil removal is inversely proportional to the surfactant content in the mesoporous material, being highest for the calcined sample but lowest for the as-synthesized sample. The kinetic of oil adsorption over the calcined material has been also studied and the data obtained fit well a second-order model.

关键词： adsorption heavy oil mesoporous silicatematerial kinetics template removal

Plant communities and reproductive phenology in mountainous regions of northern Libya

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Journal of Forestry Research 2017年第4期28卷 741-761页

作者： Ahmad K. Hegazy Hanan F. Kabiel Saud L. al-Rowaily Lesley Lovett-Doust Abd El-nasser S. al Borki Department of Botany and microbiology Faculty of ScienceCairo UniversityGiza 12613Egypt Department of Plant Production College of Food and Agricultural SciencesKing Saud UniversityRiyadhSaudi Arabia Department of Biology and Chemistry Nipissing UniversityNorth BayONCanada Department of Botany Faculty of Sciences and ArtsUniversity of BenghaziAgdabiaLibya

Within the semi-desert landscape of northern Libya, two sub-humid escarpments occur: al-Akhdar in the east and Nafusa (Jabal al-Gharbi) in the west. This study compares plant communities in the two regions, which are along an elevation gradient, in terms of species composition and diversity, frequency of different Raunkiaer life forms, and reproductive phenology. The two regions differed in species composition and life-form frequency between regions and between elevation zones within each region. Patterns were associated with the lower rainfall and lower moisture-holding capacity of soils at Nafusa, resulting in more xeric conditions. Only 13% of species were shared between the two regional landscapes. Species diversity, life-form frequency, and duration of the flowering-fruiting phenophase were all affected by elevation above sea level. The duration of flowering and fruiting in spring and fall was associated with environmental conditions, although there were different thresholds in the two regions. There was both a spring and fall episode of flowering at Nafusa, but only spring flowering at al-Akhdar. It is anticipated that there will be a gradual shift of plant communities to higher elevations and loss of certain sensitive species in response to ongoing climate change.

关键词： altitudinal gradient Raunkiaer life forms Reproductive phenology Southern mediterranean

Joint simulation of cross-correlated ore grades and geological domains:an application to mineral resource modeling

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Frontiers of Earth Science 2023年第2期17卷 417-436页

作者： nasser mADANI mohammad malEKI School of mining and Geosciences Nazarbayev UniversityAstana 010000Kazakhstan Department of metallurgical and mining Engineering Universidad Católica del NorteAntofagasta 1270709Chile

Spatial modeling of ore grades is frequently impacted by the local variation in geological domains such as lithological characteristics,rock types,and geological *** this information may lead to biased results in the final ore grade block model,subsequently impacting the downstream processes in a mining chain *** the current practice of ore body evaluation,which is known as stochastic cascade/hierarchical geostatistical modeling,the geological domain is first characterized,and then,within the geological model,the ore grades of interest are *** practice may be unrealistic in the case when the variability in ore grade across the boundary is gradual,following a smooth *** reproduce such characteristics,the cross dependence that exists between the ore grade and geological formations is considered in the conventional joint simulation between continuous and categorical ***,when using this approach,only one ore variable is considered,and its relationship with other ore grades that may be available at the sample location is *** this study,an alternative approach to jointly model two cross-correlated ore grades and one categorical variable(i.e.,geological domains)with soft contact relationships that exist among the geological domains is *** statistical and geostatistical tools are provided for variogram inference,Gibbs sampling,and conditional *** algorithm is also tested by applying it to a Cu deposit,where the geological formations are managed by the local and spatial distribution of two cross-correlated ore grades,Cu and Au,throughout the *** results show that the proposed algorithm outperforms other geostatistical techniques in terms of global and local reproduction of statistical parameters.

关键词： geostatistical simulation categorical variable continuous variable geological domain variogram inference

FRACTIONal HalANAY INEQUalITY AND APPLICATION IN NEURal NETWORK THEORY

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Acta mathematica Scientia 2019年第6期39卷 1605-1618页

作者： nasser-eddine TATAR King Fahd University of Petroleum and minerals Department of Mathematics and Statistics

The (integer order) Halanay inequality with distributed delays is extended to the fractional order case. It is proved that solutions decay to zero as a mittag-Leffler function as time goes to infinity provided that the delay feedback are bounded by similar *** application to a problem arising in neural network theory is provided showing that the equilibrium is mittag-Leffler stable.

关键词： Hopfield neural network mittag-Leffler stability Caputo fractional derivative fractional Halanay inequality

Post-bulbar duodenal ulcer with anterior perforation with kissing ulcer and duodenocaval fistula:A case report and review of literature

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World Journal of Clinical Cases 2022年第25期10卷 9071-9077页

作者： nasser alzerwi Department of Surgery College of MedicineMajmaah UniversityRiyadh 66RiyadhSaudi Arabia

BACKGROUND A post-bulbar duodenal ulcer(PBDU)is an ulcer in the duodenum that is distal to the duodenal *** may coexist with a synchronous posterior ulcer in rare occurrences,resulting in a kissing ulcer(KU).Duodenocaval fistula(DCF)is another uncommon but potentially fatal complication related to *** is limited knowledge of the scenarios in which PBDU is complicated by KU and DCF *** SUmmARY A 22-year-old man was admitted to the emergency department with abdominal pain,stiffness,and *** X-ray showed pneumoperitoneum,suggesting a perforated *** revealed a KU with anterior perforation and a *** Kocherization,venorrahphy was used to control caval *** to the critical condition of the patient,only primary duodenorrahphy with gastrojejunostomy was performed as a damage control ***,later,the patient developed obstructive jaundice and leakage,and two additional jejunal perforations were *** to the poor condition of the duodenum and the involvement of the ampulla in the posterior ulcer,neither primary repair nor pancreatic-free duodenectomy and ampull-oplasty/ampullary reimplantation were considered viable;therefore,an emergency pancreaticoduodenectomy was performed,along with resection and anastomosis of the two jejunal *** patient had a smooth recovery after surgery and was discharged after 27 *** The timely diagnosis of PBDU and radical surgery can aid in the smooth recovery of patients,even in the most complex cases.

关键词： Duodenal ulcer Duodenocaval fistula Kissing ulcer Emergency Whipple’s surgery Case report