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Synthesis and Characterization of Biphasic Calcium Phosphate Doped with Zirconia

材料科学与工程（中英文B版） 2011年第1期1卷 34-42页

作者： sam＇an m. masudi manal Farea Ahmad F. masudi meor Y. m. Sulaiman Zainul A. Ration Dasmawati mohamad Comelis H Pameijer School of Dental Sciences University of Science Malaysia 16150 Kubang Kerian Kelantan Malaysia Faculty of Chemical Engineering University of Malaya 50603 Kuala Lumpur Malaysia malaysian Nuclear Agency Bangi 43000 Kajang Selangor Malaysia Professor Emeritus University of Connecticut Farmington CT USA

Biphasic Calcium Phosphate (BCP) is bioactive and bioresorbable which can be controlled by manipulating the HA to β-TCP ratio. However, the biomedical uses of BCP are limited to non-load bearing applications. ZrO2 can be used to produce a biocomposite Zirconia (Zr) and calcium phosphate biomaterial for better strength, x-ray contrast and opacity. To determine the characterization of BCP-Zr material, we carried out a chemical and structural analysis of Zr-doped BCP by means of Transmission and Scanning Electron microscopy and Energy Dispersive X-ray analysis. BCP with Zr was prepared using organic diethyl hexyl phosphoric acid (DEHPA) as the source for phosphate. Sixty gram calcium hydroxide [Ca (OH)2] was diluted in 300 ml distilled water and activated using a magnetic stirrer at 70 °C for 2 h and was subsequently cooled to room temperature. Next, 5 g of zirconyl chloride octahydrate was diluted in 150 ml 4 m HCl, stirred and heated to 70 ?C until zirconyl chloride octahydrate was fully dissolved. The solution was then mixed with 300 ml DEHPA, stirred for 20 minutes and separated by using a separating funnel glassware. Two layers were formed; the bottom layer (supernatant) was discarded while the upper layer, the organophosphate solution, was then added slowly (drop by drop) using a separating funnel to the Ca (OH)2 solution, while being stirred continuously for 2 h. This mixture was left overnight, thus allowing for the formation of a BCP-Zr precipitate. The precipitate was then filtered and the BCP-Zr precipitate was collected and stored in a glass beaker covered with aluminum foil for drying in an oven at 72 °C for 24 h. The BCP-Zr precipitate was then placed in a clay crucible for the calcination process. This was carried out in a furnace at 1,000 °C for 3 h resulting in BCP doped Zirconia powder. The result showed that some crystalline structural changes occurred with the addition of Zr which resulted in formation of BCP. Zr appeared in monoclinic, tetragonal a

关键词：氧化锆粉末 P掺杂磷酸钙合成双相 Ca(OH)2 磁力搅拌器八水氢氧化钡

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Anti-diabetic potential of apigenin,luteolin,and baicalein via partially activating PI3K/Akt/GLUT-4 signaling pathways in insulin-resistant HepG2 cells

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Food Science and Human Wellness 2023年第6期12卷 1991-2000页

作者： Lingchao miao Haolin Zhang meng sam Cheong Ruting Zhong Paula Garcia-Oliveira miguel A.Prieto Ka-Wing Cheng mingfu Wang Hui Cao Shaoping Nie Jesus Simal-Gandara Wai San Cheang Jianbo Xiao Institute of Chinese medical Sciences University of MacaoMacao 999078China Department of Analytical Chemistry and Food Science Faculty of Food Science and TechnologyUniversity of Vigo-Ourense CampusOurense E-32004Spain Institute for Advanced Study Shenzhen UniversityShenzhen 508060China School of Biological Sciences The University of Hong KongHong Kong 999077China College of Food Science and Technology Guangdong Ocean UniversityGuangdong Provincial Key Laboratory of Aquatic Product Processing and SafetyGuangdong Province Engineering Laboratory for Marine Biological ProductsGuangdong Provincial Engineering Technology Research Center of SeafoodKey Laboratory of Advanced Processing of Aquatic Product of Guangdong Higher Education InstitutionZhanjiang 524088China State Key Laboratory of Food Science and Technology China-Canada Joint Lab of Food Science and Technology(Nanchang)Nanchang UniversityNanchang 330047China International Research Center for Food Nutrition and Safety Jiangsu UniversityZhenjiang 212013China

Dietary flavonoids are abundant in natural plants and possess multiple pharmacological and nutritional *** this study,apigenin,luteolin,and baicalein were chosen to evaluate their anti-diabetic effect in high-glucose and dexamethasone induced insulin-resistant(IR)HepG2 *** flavonoids improves the glucose consumption and glycogen synthesis abilities in IR-HepG2 cells via activating glucose transporter protein 4(GLUT4)and phosphor-glycogen synthase kinase(GSK-3β).These fl avonoids signifi cantly inhibited the production of reactive oxygen species(ROS)and advanced glycation end-products(AGEs),which were closely related to the suppression of the phosphorylation form of NF-κB and *** expression levels of insulin receptor substrate-1(IRS-1),insulin receptor substrate-2(IRS-2)and phosphatidylinositol 3-kinase(PI3K)/protein kinase B(Akt)pathway in IR-HepG2 cells were all partially activated by the fl avonoids,with variable ***,the intracellular metabolic conditions of the fl avonoids were also evaluated.

关键词： Apigenin Luteolin Baicalein Insulin-resistant HepG2 cells Signaling pathway Reactive oxygen species(ROS) Advanced glycation end-products(AGEs) Glycogen synthase kinase(GSK-3β) Glucose transporter protein 4(GLUT4)

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Spatiotemporal dynamics of ecosystem fires and biomass burning-induced carbon emissions in China over the past two decades

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Geography and Sustainability 2020年第1期1卷 47-58页

作者： Anping Chen Rongyun Tang Jiafu mao Chao Yue Xiran Li mengdi Gao Xiaoying Shi mingzhou Jin Daniel Ricciuto sam Rabin Phillippe Ciais Shilong Piao Department of Biology Colorado State UniversityFort CollinsCO 80523USA Graduate Degree Program in Ecology Colorado State UniversityFort CollinsCO 80523USA Department of Industrial and Systems Engineering University of TennesseeKnoxvilleTN 37996USA Environmental Sciences Division and Climate Change Science Institute Oak Ridge National LaboratoryOak RidgeTN 37831USA State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Northwest Agriculture&Forestry UniversityYanglingShanxi 712100China College of Urban and Environmental Sciences Central China Normal UniversityWuhanHubei 430079China Sino-French Institute for Earth System Science College of Urban and Environmental SciencesPeking UniversityBeijing 100871China Atmospheric Environmental Research(ImK-IFU) Institute of Meteorology and Climate ResearchKarlsruhe Institute of Technology(KIT)Kreuzeckbahnstraße 19Garmisch-Partenkirchen 82467Germany LSCE UMR CEA-CNRSBat.709CEL’Orme des MerisiersGif-sur-Yvette 91191France

Fire is a major type of disturbance that has important influences on ecosystem dynamics and carbon *** our understanding of ecosystem fires and their carbon cycle consequences is still limited,largely due to the difficulty of large-scale fire monitoring and the complex interactions between fire,vegetation,climate,and anthropogenic ***,using data from satellite-derived fire observations and ecosystem model simulations,we performed a comprehensive investigation of the spatial and temporal dynamics of China’s ecosystem fire disturbances and their carbon emissions over the past two decades(1997–2016).Satellite-derived results showed that on average about 3.47-4.53×10^(4) km^(2) of the land was burned annually during the past two decades,among which annual burned forest area was about 0.81-1.25×10^(4) km^(2),accounting for 0.33-0.51%of the forest area in *** burning emitted about 23.02 TgC per *** to satellite products,simulations from the Energy Exascale Earth System Land model(ELm)strongly overestimated China’s burned area and fire-induced carbon *** burned area and fire-induced carbon emissions were high for boreal forest in Northeast China’s Daxing’anling region and subtropical dry forest in South Yunnan,as revealed by both the satellite product and the model *** results suggest that climate and anthropogenic factors play critical roles in controlling the spatial and seasonal distribution of China’s ecosystem fire *** findings highlight the importance of multiple complementary approaches in assessing ecosystem fire disturbance and its carbon *** studies are required to improve the methods of observing and modelling China’s ecosystem fire disturbances,which will provide valuable information for fire management and ecosystem sustainability in an era when both human activities and the natural environment are rapidly changing.

关键词： Fire emission Burned area Fire models China

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轿跑时代？

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汽车杂志 2007年第1期 248-251页

作者： sam

最近．汽车界经常提到的一个词——“轿跑车”，雪铁龙C4 Coupe打着轿跑车的概念进入中国市场，标致407Coupe也是所谓纯正法国轿跑；2006北京车展中自主品牌有诸如华展m3．海马轿跑车等国产原倒轿龅车亮相．一时间让人不禁要问：家用轿... 详细信息

最近．汽车界经常提到的一个词——“轿跑车”，雪铁龙C4 Coupe打着轿跑车的概念进入中国市场，标致407Coupe也是所谓纯正法国轿跑；2006北京车展中自主品牌有诸如华展m3．海马轿跑车等国产原倒轿龅车亮相．一时间让人不禁要问：家用轿车还没普及的今天．中国又开始了轿跑车时代？

关键词：中国市场 Coupe 轿跑车家用轿车北京车展雪铁龙汽车标致

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CLASS STRUGGLES

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The World of Chinese 2021年第6期 38-43页

作者： sam DAVIES 不详

On paper,Xiaoxin’s schedule looks like that of any other overburdened teenager in China’s education system:crammed full of English,math,Chinese,and political theory courses from 6:40 *** 8 p.m.,with additional cours... 详细信息

关键词： CLASS system theory

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A Floating Island Treatment System for the Removal of Phosphorus from Surface Waters

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Engineering 2018年第5期4卷 597-609页

作者： mark T. Brown Treavor Boyer R.J. Sindelar sam Arden Amar Persaud Sherry Brandt-Williams Department of Environmental Engineering Sciences University of Florida Gainesville FL 32611 USA St. Johns River Water management District Palatka FL 32177 USA

The goal of this project was to design, build, and test a pilot-scale floating modular treatment system for total phosphorus （TP） removal from nutrient-impaired lakes in central Florida, USA. The treatment sys-tem consisted of biological and physical-chemical treatment modules. First, investigations of prospective biological and physical-chemical treatment processes in mesocosms and in bench-scale experiments were conducted. Thirteen different mesocosms were constructed with a variety of substrates and combi-nations of macrophytes and tested for TP and orthophosphate （PO4-^3） removal efficiencies and potential areal removal rates. Bench-scale jar tests and column tests of seven types of absorptive media in addition to three commercial resins were conducted in order to test absorptive capacity. Once isolated process testing was complete, a floating island treatment system （FITS） was designed and deployed for eight months in a lake in central Florida. Phosphorus removal efficiencies of the mesocosm systems averaged about 40%-50%, providing an average uptake of 5.0 g.m ^2.a ^1 across all mesocosms. The best-performing mesocosms were a submerged aquatic vegetation （SAV） mesocosm and an algae scrubber （AGS）, which removed 20 and 50 mg.m ^2.d ^1, respectively, for an average removal of 5.5 and 12.0 g.m ^2.a ^1 for the SAV and AGS systems, Of the absorptive media, the best performance was alum residual （AR）, which reduced PO4-^3 concentrations by about 75% after 5 min of contact time. Of the commercial resins tested, the PhosX resin was superior to the others, removing about 40% of phosphorus after 30 rain and 60% after 60min. Under baseline operation conditions during deployment, the FITS exhibited mean PO4-^3 removal efficiencies of 53%; using the 50th and 90th percentile of PO4-^3 removal during deployment, and the footprint of the FITS system, yielded efficiencies for the combined FITS system of 56% and 86%, respectively, and areal phosphorus removal rates between 8.9

关键词： Phosphorus removal Lake ecosystem Floating island treatment

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Dielectric Analysis of Response Time in Electrorheological Fluids Developed for medical Devices

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American Journal of Analytical Chemistry 2011年第2期2卷 85-92页

作者： Naullage I. Perera manik Pavan maheswaram Dhruthiman mantheni Dhanuja D. Perera m. Ellen matthews Alan Riga Tobili sam Yellowe 不详

Three electrorheological fluids (ERFs) of recently synthesized *** and Cellulose fluids as well as a commercial product from Fludicon? (Germany), were evaluated with a two-electrode probe unit and by Dielectric Analysis (DEA). The study was a part of an ongoing medical device development project. The dielectric response times were calculated using the critical peak frequency in a corresponding Debye plot of Tan Delta (loss factor/permittivity) vs. log frequency. The DEA revealed the response times (tau, τ) in ms. The Fludicon? ERF was DEA durable (repeat cycles produced same results) and the τ was temperature dependent: 16 ms at 25°C and 0.16 ms at 80°C. The Cellulose ERF was somewhat DEA durable and the τ was 5.5 ms at 25°C and 0.21 ms at 80°C. The response times were logarithmic with the temperature (°C) with a correlation coefficient of >0.98 for the Cellulose and Fludicon? ERFs. The Polyaniline ERF had a τ of 53 ms at 25°C in the 1st DEA run and there was no indication of a τ for the remaining DEA tests.

关键词： ERF Tan Delta DEA Fibrillation Debye Plot Response Time

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Alzheimer’s Disease Aβ-Amyloid Plaque morphology Varies According to APOE Isotype

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World Journal of Neuroscience 2023年第3期13卷 118-133页

作者： Ina Caesar K. Peter R. Nilsson Per Hammarström mikael Lindgren Stefan Prokop James Schmeidler Vahram Haroutunian David m. Holtzman Patrick R. Hof sam Gandy Department of Neurology Icahn School of Medicine at Mount Sinai New York NY USA Department of Physics Chemistry and Biology Link&#246ping University Link&#246ping Sweden Department of Physics Norwegian University of Science and Technology Trondheim Norway Department of Neuropathology Charité Universit&#228tsmedizin Berlin Berlin Germany Department of Psychiatry Icahn School of Medicine at Mount Sinai New York NY USA Alzheimer’s Disease Research Center Icahn School of Medicine at Mount Sinai New York NY USA James J. Peters VA medical Center Bronx NY USA Nash Family Department of Neuroscience and Friedman Brain Institute Icahn School of Medicine at Mount Sinai New York NY USA Department of Neurology Hope Center for Neurological Disorders Knight Alzheimer’s Disease Research Center Washington University St. Louis MO USA Ronald m. Loeb Center for Alzheimer’s Disease Icahn School of Medicine at Mount Sinai New York NY USA

Background: The apolipoprotein E (APOE, gene;apoE, protein) ε4 allele is the most commonly identified genetic risk factor for typical late-onset sporadic Alzheimer’s disease (AD). Each APOE ε4 allele roughly triples the relative risk for AD compared to that of the reference allele, APOE ε3. methods: We have employed hyperspectral fluorescence imaging with an amyloid-specific, conformation-sensing probe, p-FTAA, to elucidate protein aggregate structure and morphology in fresh frozen prefrontal cortex samples from human postmortem AD brain tissue samples from patients homozygous for either APOE ε3 or APOE ε4. Results: As expected APOE ε4/ε4 tissues had a significantly larger load of CAA than APOE ε3/ε3. APOE isoform-dependent morphological differences in amyloid plaques were also observed. Amyloid plaques in APOE ε3/ε3 tissue had small spherical cores and large coronas while amyloid plaques in APOE ε4/ε4 tissues had large irregular and multi-lobulated plaques with relatively smaller coronas. Despite the different morphologies of their cores, the p-FTAA stained APOE ε3/ε3 amyloid plaque cores had spectral properties identical to those of APOE ε4/ε4 plaque cores. Conclusions: These data support the hypothesis that one mechanism by which the APOE ε4 allele affects AD is by modulating the macrostructure of pathological protein deposits in the brain. APOE ε4 is associated with a higher density of amyloid plaques (as compared to APOE ε3). We speculate that multilobulated APOE ε4-associated plaques arise from multiple initiation foci that coalesce as the plaques grow.

关键词： Alzheimer’s Disease Amyloid Apolipoprotein Luminescent Conjugated Oligothiophenes Hyperspectral Separation

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Fecal lactoferrin accurately reflects mucosal inflammation in inflammatory bowel disease

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World Journal of Gastrointestinal Pathophysiology 2019年第5期10卷 54-63页

作者： marrieth G Rubio Kofi Amo-mensah James m Gray Vu Q Nguyen sam Nakat Douglas Grider Kim Love James H Boone Dario Sorrentino IBD Center-Division of Gastroenterology Virginia Tech Carilion School of MedicineRoanokeVA 24016United States Department of Radiology Virginia Tech Carilion School of MedicineRoanokeVA 24016United States Department of Basic Science Education Virginia Tech Carilion School of medicine and Dominion Pathology Associates RoanokeVA 24016United States K.R.Love Quantitative Consulting and Collaboration AthensGA 30605United States Research and Development TECHLAB IncBlacksburgVA 24060United States Department of Clinical and Experimental medical Sciences University of Udine School of MedicineUdine 33100Italy

BACKGROUND Studies have demonstrated a potential role for fecal biomarkers such as fecal calprotectin(FC)and fecal lactoferrin(FL)in monitoring inflammatory bowel diseases(IBD)-Crohn's disease(CD)and ulcerative colitis(UC).However,their correlation to endoscopic scores,disease severity and affected intestinal surface has not been extensively *** To correlate FL,and for comparison white blood cell(WBC)and C-reactive protein(CRP),with endoscopic scores,disease extent and location in CD and *** Retrospective analysis in 188 patients who had FL,CRP and WBC determined within 30 d of *** location,disease extent(number of intestinal segments involved),disease severity(determined by endoscopic scores),timing of FL testing in relation to colonoscopy,as well as the use of effective fast acting medications(steroids and biologics)between colonoscopy and FL measurement,were *** In 131 CD and 57 UC patients,both CRP and FL-but not WBC-distinguished disease severity(inactive,mild,moderate,severe).In patients receiving fastacting(steroids or biologics)treatment in between FL and colonoscopy,FL showed a higher correlation to endoscopic scores when tested before vs after the procedure(r=0.596,Pmple Endoscopic Score for CD;and r=0.402,P=0.01 vs r=0.054 P=0.84 for Disease Activity Index).Finally,FL was significantly correlated with the diseased mucosal surface(colon-ileocolon>small bowel)and the number of inflamed colon *** FL and CRP separated disease severity categories with FL showing lower discriminating *** showed a close correlation with the involved mucosal surface and with disease extent and was more closely correlated to endoscopy when determined before the procedure–this indicating that inflammatory activity changes associated with therapy might be rapidly reflected by FL *** can accurately and timely characterize intestinal inflammation in IBD.

关键词： Inflammatory bowel disease Crohn’s disease Ulcerative colitis Fecal lactoferrin C-reactive protein White blood cell count mucosal inflammation

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Direct Current Generation in Carbon Nanotubes by Terahertz Field

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World Journal of Condensed matter Physics 2016年第1期6卷 56-62页

作者： Sulemana S. Abukari Frederick sam samuel Y. mensah Natalia G. mensah Rabiu musah Anthony Twum Patrick m. Amoah Alfred Owusu Department of Physics Laser and Fibre Optics Centre University of Cape Coast Cape Coast Ghana Department of mathematics University of Cape Coast Cape Coast Ghana Department of Applied Physics University for Development Studies Navorongo Ghana

We report on a theoretical investigation of a direct current generation in carbon nanotubes (CNTs) that are stimulated axially by terahertz (THz) field. We consider the kinetic approach based on the semiclassical Boltzmann’s transport equation with constant relaxation time approximation, together with the energy spectrum of an electron in the tight-binding approximation. Our results indicate that for strong THz-fields, there is simultaneous generation of DC current in the axial and circumferential directions of the CNTs, even at room temperature. We found that a THz-field can induce a negative conductivity in the CNTs that leads to the THz field induced DC current. For varying amplitude of the THz-field, the current density decreases rapidly and modulates around zero with interval of negative conductivity. The interval decreases with increasing the amplitude of the THz-field. We show that the THz-field can cause fast switching from a zero DC current to a finite DC current due to the quasi-ballistic transport, and that electron scattering is a necessary condition for switching.

关键词： Carbon Nanotubes Terahertz Fields DC Voltage Generation Negative Conductivity Electron Scattering Ballistic Transport

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