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Characterization of some bacterial strains isolated from the Egyptian eastern and northern coastlines with antimicrobial activity of Bacillus zhangzhouensis OmER4

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Acta Oceanologica Sinica 2022年第3期41卷 86-93页

作者： mohamed O.Soliman Waleed B.Suleiman mohamed m.Roushdy Eman N.Elbatrawy Ahmed m.Gad Department of Botany and microbiology Faculty of ScienceAl-Azhar UniversityCairo 11884Egypt The Regional Center for mycology and Biotechnology Al-Azhar UniversityCairo 11884Egypt microbiology Laboratory Marine Environmental DivisionNational Institute of Oceanography and FisheriesAlexandria 11865Egypt

marine microorganisms were considered to be important sources of marine bioactive *** major objective of the study was to isolate and characterize bacteria with antimicrobial activities from the various marine environment of *** this respect,thirty-five bacterial isolates were recovered from sediment samples collected from different spots along the Egyptian Red Sea coastline and Alexandria coastline during the summer season of 2017 and *** to the morphological,physiological,and biochemical characteristics,the bacterial isolates were clustered into 13 groups designated as A,B,…,***,14 Gram-negative and 21 Grampositive bacteria were *** isolated bacterial strains were screened for their potentiality for antimicrobial agent(s)production against ten indicator *** mo13 was showed high antimicrobial activity against all empirical ***,the most promising marine bacterial isolate with code mO13 was identified as Bacillus zhangzhouensis OmER4 according to the phenotypic characterization through morphological,physiological,and biochemical tests as well as genotypic characterization through the 16 S rDNA *** bioactive components were extracted with ethyl acetate,then analyzed using GC-mS and the substantial component was recognized as phenol,2,4-bis(1,1-dimethyl ethyl).

关键词： marine bacteria natural product Egyptian coastline antimicrobial Bacillus zhangzhouensis GC-mS characterization

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maternal body condition during latepregnancy is associated with in utero development and neonatal growth of Holstein calves

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Journal of Animal Science and Biotechnology 2021年第3期12卷 984-994页

作者： A.S.Alharthi D.N.Coleman I.A.Alhidary m.m.Abdelrahman E.Trevisi J.J.Loor Department of Animal Production College of Food and Agriculture SciencesKing Saud UniversityRiyadh 11451Saudi Arabia Department of Animal Sciences and Division of Nutritional Sciences University of IllinoisUrbanaIL 61801USA Department of Animal Sciences Food and Nutrition(DIANA)Faculty of AgricultureFood and Environmental ScienceUniversitàCattolica del Sacro Cuore29122 PiacenzaItaly

Background:Nutritional management in the dry period can alter body condition score(BCS)in dairy cows,a subjective measure of body *** such,differences in BCS during late-pregnancy not only mirror nutrient utilization by fat depots,but also can play important roles on the metabolic and hormonal *** investigated the association between cow BCS during late-pregnancy on developmental parameters and blood variables of neonatal ***-nine multiparous Holstein cows were retrospectively divided by prepartal BCS into normal BCS≤3.25(NormBCS;3.02±0.17,n=30)or high BCS≥3.75(HighBCS;3.83±0.15,n=19)*** samples were collected from cows at−10 d relative to *** weight,hip and wither height,hip width and body length were measured at birth and weekly through weaning(42 d of age)and until 9 weeks of *** blood samples were collected from the jugular vein at birth(before receiving colostrum,0 d),24 h after first colostrum and at 7,21,42 and 50 d of *** data were subjected to ANOVA using the mixed procedure of *** statistical model included day,BCS,and their ***:Dry matter intake(kg/d or%of body weight)during the last 4 weeks of pregnancy was lower(P≤0.06)in HighBCS *** concentrations of fatty acids,ceruloplasmin,and nitric oxide were greater overall(Pms with *** addition,plasma concentrations of fatty acids,albumin and urea(Pmaintained a lower postnatal body weight(P=0.04),hip and wither height,hip width,and body length,there was no difference(P>0.05)in daily starter intake and average daily gain due to maternal ***:Overall,results highlight an association between BCS during late-gestation on in utero calf development and postna

关键词： metabolism Neonate Nutritional programming Transition cow

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Asphaltene Surface Erosion in Air Plasma

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Plasma Science and Technology 2010年第1期12卷 81-86页

作者： m. VILLA m. CALIXTO-RODRIGUEZ H. mARTINEZ J. C. POVEDA P. G. REYES P. ALTUZAR Faculty of Sciences Autonomous University of the State of Mexico State of Mexico Mexico Institute of Physical Sciences Autonomous National University of Mexico 62210 Cuernavaca Morelos Mexico Energy Research Center Autonomous National University of Mexico 62580 Temixco Morelos Mexico

Optical emission spectroscopy was applied for plasma characterization during erosion of substrates of asphaltene. The amount of 100 mg of asphaltene was carefully applied to an electrode and exposed to air plasma glow discharge at a pressure of 1.0 Tort. The plasma was generated in a stainless steel discharge chamber by an AC generator with a frequency of 60 Hz and an output power of about 60 W. The electron temperature was found to be 6.88 eV, and the ion density is about 3.5×10^16 cm^-3. As the asphaltene was exposed to the air plasma, the surface was etched. The emission from molecular bands CS2,O3, N2^＋, NO, O2, CS, S2, CN, C7H7, C2, H2, C2^-, NiO, N2 and SO, and atomic line O, were observed and some of them were used to monitor the evolution of asphaltene erosion. The asphaltene weight was reduced gradually with an etching rate of about 0.844 mg/min, during the first 20 min.

关键词： optical emission spectroscopy asphaltene erosion

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Effect of void nucleation on microstructure and stress state in aluminum alloy tailor-welded blank

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Progress in Natural Science:materials International 2021年第1期31卷 77-85页

作者： L.Xing m.Zhan P.F.Gao m.Li Y.D.Dong T.Y.Wang State Key Laboratory of Solidification Processing School of Materials Science and Engineering Northwestern Polytechnical University Shaanxi Key Laboratory of High-Performance Precision Forming Technology and Equipment Key Laboratory of High Performance manufacturing for Aero Engine (Northwestern Polytechnical University) Ministry of Industry and Information Technology

The microscopic damage initiation characteristic in welded joint greatly determines the subsequent damage evolution and fracture behavior of aluminum alloy tailor-welded blank(TWB) during plastic forming. In this study, the interactive dependence of void nucleation on microstructure and stress state in the welded joint of a2219 aluminum alloy TWB was quantitatively explored by in-situ SEm testing. moreover, a micromechanical model based on actual microstructure was adopted to reveal the underlying mechanisms from the perspective of microscopic heterogeneous deformation. The results showed that three void nucleation mechanisms, including particle-cracking, interface-debonding and matrix-cracking, coexisted in the deformation at different microstructure regions and stress states. The nucleation strain of each mechanism mainly depended on the particle volume fraction, grain size and stress triaxiality. Besides, the proportions of particle-cracking and interfacedebonding greatly varied with the grain size and particle volume fraction, and the variation law changed with the stress state. The proportion of matrix-cracking had a weak dependence on the microstructure, while increased with the stress triaxiality decreasing. It made the damage initiation in aluminum alloy welded joint transit from particle-cracking dominance to matrix-cracking dominance with the stress triaxiality *** micromechanical modeling results suggested that the changes of evolutions and distributions of mises stress in particle, hydrostatic stress at interface and plastic strain in matrix with microstructure and stress state were responsible for the above effects.

关键词： Aluminum alloy Welded joint Void nucleation microstructure Stress state micromechanical model

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Arabidopsis ADC1 functions as an Nδ-acetylornithine decarboxylase

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Journal of Integrative Plant Biology 2020年第5期62卷 601-613页

作者： Yann-Ru Lou Sheaza Ahmed Jian Yan Adewale m.Adio Hannah m.Powell Paul F.morris Georg Jander Boyce Thompson Institute for Plant Research IthacaNY 14853USA Department of Biological Sciences Bowling Green State UniversityBowling GreenOH 43403USA Key Laboratory of Agro-Environment in the Tropics Ministry of Agriculture and Rural AffairsSouth China Agricultural UniversityGuangzhou 510642China Department of Biochemistry and molecular Biology Michigan State UniversityEast LansingMI 48824USA Bayer Crop Science 700 Chesterfield Parkway WestChesterfieldMO 63017USA

Polyamines are small aliphatic amines found in almost all organisms,ranging from bacteria to plants and *** most plants,putrescine,the metabolic precursor for longer polyamines,such as spermidine and spermine,is produced from arginine,with either agmatine or ornithine as *** we show that Arabidopsis thaliana(Arabidopsis)arginine de-carboxylase 1(ADC1),one of the two known arginine decarboxylases in Arabidopsis,not only synthesizes agmatine from arginine,but also converts *** to *** analyses indicate that duplication and neofunctionalization of ADC1 and NATA1,the enzymes that synthesize Nδ-acetylormithine in Arabidopsis,co-occur in a small number of related species in the *** ADC2,which is localized in the chloroplasts,ADC1 is in the endoplasmic reticulum together with NATA1,an indication that these two enzymes have access to the same substrate ***,these results are con-sistent with a model whereby NATA1 and ADC1 to-gether provide a pathway for the synthesis of N-acetylputrescine in Arabidopsis.

关键词： Arabidopsis Phylogenetic Together

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Solid particle erosion studies of thermally deposited alumina-titania coatings on an aluminum alloy

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International Journal of minerals,metallurgy and materials 2021年第7期28卷 1186-1193页

作者： Chellaganesh Duraipandi Adam Khan m Winowlin Jappes J.T. Nouby mGhazaly Peter madindwa mashinini School of Automotive and mechanical Engineering and Centre for Surface Engineering Kalasalingam Academy of Research and EducationKrishnankoil 626126VirudhunagarTamilnaduIndia mechanical Engineering Department Faculty of EngineeringSouth Valley UniversityQena 83523Egypt Department of mechanical and Industrial Engineering Technology University of JohannesburgDoornfontein CampusJohannesburg 2028South Africa

Thermal barrier coatings are widely used as surface modifications to enhance the surface properties of the material and protect from surface degradations such as erosion and ***-based coatings are highly recommended to increase wear resistance in the indus-trial *** this paper,an alumina-titania ceramic powder was deposited on an aluminum alloy using an atmospheric plasma spray *** investigations were performed to study the behavior and erosion rate of the *** particle erosion studies were performed by varying the particle velocity and particle flow *** angle impingement and stand-off distance were constant for *** base metal has a clinging effect and the mass change was negative at a maximum particle flow rate of 4 g·min^(−1).Under the same process conditions,the coated sample had a reduced lifetime and reached a maximum erosion rate of 0.052(Δg/g).The solid particle erosion studies confirmed that the base metal aluminum alloy had severe surface damage with erodent reinforcement when compared to the coated *** influence of the particle velocity,particle flow rate,and input process parameters were also identified.

关键词： erosion alumina wear velocity microstructure

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Crushing and embedment of proppant packs under cyclic loading: An insight to enhanced unconventional oil/gas recovery

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Geoscience Frontiers 2021年第6期12卷 376-393页

作者： K.m.A.S.Bandara P.G.Ranjith T.D.Rathnaweera W.A.m.Wanniarachchi S.Q.Yang Department of Civil Engineering Monash UniversityBuilding 60MelbourneVictoria3800Australia State Key Laboratory for Geomechanics and Deep Underground Engineering School of Mechanics and Civil EngineeringChina University of Mining and TechnologyXuzhou 221116China

Crushing and embedment are two critical downhole proppant degradation mechanisms that lead to a significant drop in production outputs in unconventional oil/gas stimulation projects. These persistent production drops due to the non-linear responses of proppants under reservoir conditions put the future utilization of such advanced stimulation techniques in unconventional energy extraction in doubt. The aim of this study is to address these issues by conducting a comprehensive experimental approach. According to the results, whatever the type of proppant, all proppant packs tend to undergo significant plastic deformation under the first loading ***, the utilization of ceramic proppants(which retain proppant pack porosity up to 75%), larger proppant sizes(which retain proppant pack porosity up to 15.2%) and higher proppant concentrations(which retain proppant pack porosity up to 29.5%) in the fracturing stimulations with higher in-situ stresses are recommended to de-escalate the critical consequences of crushing associated issues. Similarly, the selection of resin-coated proppants over ceramic and sand proppants may benefit in terms of obtaining reduced proppant *** addition, selection of smaller proppant sizes and higher proppant concentrations are suggested for stimulation projects at depth with sedimentary formations and lower in-situ stresses where proppant embedment predominates. Furthermore, correlation between proppant embedment with repetitive loading cycles was ***, microstructural analysis of the proppant-embedded siltstone rock samples revealed that the initiation of secondary induced fractures. Finally, the findings of this study can greatly contribute to accurately select optimum proppant properties(proppant type, size and concentration) depending on the oil/gas reservoir characteristics to minimize proppant crushing and embedment effects.

关键词： Proppant micro-CT analysis Proppant crushing Proppant embedment Secondary induced fractures Cyclic loading

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Increase of Diagnostic mirror Lifetime Using TiN Coated Stainless Steel by Using a Plasma Focus Device

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Plasma Science and Technology 2013年第5期15卷 485-488页

作者： K. mikaili AGAH m. GHORANNEVISS m. K. SALEm A. Salar ELAHI S. mOHAmmADI R. ARVIN Plasm a Physics Research Center Science and Research Branch Islamic Azad University

Plasma-surface interaction experiments on TiN coated stainless steel 316L （S.S.316L） using a plasma focus （PF） device have been performed in an attempt to investigate whether we can use the hardness property of TiN against erosion to increase the lifetime of the mirrors used in plasma diagnostics equipment. Firstly, two similar S.S.316L samples were chosen for this purpose. One of the samples was coated with TiN by using a PF device, while the other was kept intact as a reference for investigating the effect of TiN coating. Then, in order to study the coating effects, these samples were exposed to 200 shots of hydrogen plasma with a total duration of 7 s in a tokamak. Before and after exposure, samples were analyzed by using atomic force microscopy （AFm）, scanning electron microscopy （SEm）, X-ray diffraction （XRD） and a spectrophotometer. It was found that the uncoated sample was severely damaged, its reflection dropped significantly, and it developed some cracks and lines, while no significant change was observed on the surface characteristic of the coated sample. moreover the weight loss of the uncoated sample was higher in comparison to the coated one. Therefore the results of this experiment showed that the coating of S.S.316L by TiN using a PF device is a useful method to strengthen it against plasma erosion and with further optimization it could possibly be used in preparing plasma diagnostics mirrors.

关键词： PF device tokamak TiN diagnostics mirrors AFm SEm XRD

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System Identification modeling and Unstable Behavior of the Dynamics of Flows within the Tip Region of an Axial Compressor Blade Passage

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Journal of Thermal Science 2016年第2期25卷 109-116页

作者： STERBENTZ Dane m. PRASAI Sujan HOFLE mary m. WALTERS Thomas LIN Feng LI Ji-chao BOSWORTH Ken SCHOEN marco P. Idaho State University Measurement and Control Engineering Research Center Institute of Engineering Thermophysics Chinese Academy of Sciences

In recent years, the correlation coefficient of pressure data from the same blade passage in an axial compressor unit has been used to characterize the state of flow in the blade passage. In addition, the correlation coefficient has been successfully used as an indicator for active control action using air injection. In this work, the correlation coefficient approach is extended to incorporate system identification algorithms in order to extract a mathematical model of the dynamics of the flows within a blade passage. The dynamics analyzed in this research focus on the flow streams and pressure along the rotor blades as well as on the unsteady tip leakage flow from the rotor tip gaps. The system identification results are used to construct a root locus plot for different flow coefficients, starting far away from stall to near stall conditions. As the compressor moves closer to stall, the poles of the identified models move towards the imaginary axis of the complex plane, indicating an impending instability. System frequency data is captured using the proposed correlation based system identification approach. Additionally, an oscillatory tip leakage flow is observed at a flow coefficient away from stall and how this oscillation changes as the compressor approaches stall is an interesting result of this research. Comparative research is analyzed to determine why the oscillatory flow behavior occurs at a specific sensor location within the tip region of the rotor blade.

关键词： axial compressor correlation coefficient oscillatory behavior system identification

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Neuronal injury in the motor cortex after chronic stroke and lower limb motor impairment: a voxelbased lesion symptom mapping study

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Neural Regeneration Research 2014年第7期9卷 766-772页

作者： Alexandria m.Reynolds Denise m.Peters Jennifer m.C.Vendemia Lenwood P.Smith Raymond C.Sweet Gordon C.Baylis Debra Krotish Stacy L.Fritz Department of Psychology Barnwell College University of South Carolina Department of Exercise Science University of South Carolina Department of Psychology University of South Carolina Neurosurgery Center University of South Carolina School of Medicine Western Kentucky University University of South Carolina School of medicine

many studies have examined motor impairments using voxel-based lesion symptom mapping, but few are reported regarding the corresponding relationship between cerebral cortex injury and lower limb motor impairment analyzed using this technique. This study correlated neuro- nal injury in the cerebral cortex of 16 patients with chronic stroke based on a voxel-based lesion symptom mapping analysis. Neuronal injury in the corona radiata, caudate nucleus and putamen of patients with chronic stroke could predict walking speed. The behavioral measure scores were consistent with motor deficits expected after damage to the cortical motor system due to stroke. These findings suggest that voxel-based lesion symptom mapping may provide a more accurate prognosis of motor recovery from chronic stroke according to neuronal injury in cerebral motor cortex.

关键词： nerve regeneration magnetic resonance imaging stroke cerebral cortex motor cortex voxel-based lesion symptom mapping motor function prognosis neural regeneration

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