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Physicomechanical Properties of Su.tainable Wood Plastic Composites of Tropical Sawdu.t and Thermoplastic Waste for Possible u.ilization in the Wood Indu.try

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Jou.nal of Su.tainable Bioenergy Systems 2023年第4期13卷 149-171页

作者： Ju.e I. Du.u.ku.Patrick A. C. Okoye theresa u. onuegbu Valentine I. Onwu.eme Nkechi H. Okoye Joseph O. Nwadiogbu Department of Pu.e and Indu.trial Chemistry Nnamdi Azikiwe University Awka Nigeria Department of Pu.e and Indu.trial Chemistry Chukwuemeka Odumegwu Ojukwu University Uli Nigeria

This work investigated and qu.ntified the physicomechanical properties of flat-pressed wood plastic composites produ.ed with recycled polyethylene terephthalate, recycled polyethylene and sawdu.t derived from selected tropical timbers, namely, Nau.lea diderrichii, Brachystegia eu.ycoma, Erythrophleu. su.veolens and Prosopis africana, for possible u.ilization in the wood indu.try. The compou.ding of the polymer blends of the precu.sor plastics, namely recycled PET (rPET) and recycled PE (rPE) with the sawdu.t (SD) from the selected timbers to produ.e the desired wood rPET/rPE composites was carried ou. via the flat press method. The characterization of the physicomechanical properties of the wood plastic composites (WPCs) produ.ed, su.h as the density, hardness, flexu.al strength, u.timate tensile strength, elongation %, thickness swelling and water absorption capacity was carried ou. u.ing methods based mainly on the Eu.opean Committee for Standardization (CEN) and the American Society for Testing Materials (ASTM) standards. The resu.ts of the investigation on the resu.tant composites indicated that changes in the SD content affected the density of flat-pressed WPCs in line with literatu.e. Generally, it was observed that as wood du.t increased and PET content decreased, the density of composites decreased with some deviations as expected probably du. to the anisotropic natu.e of the wood fillers. The analysis of variance (ANOVA) revealed that there was a statistically significant variation in the wood composites of Nu.lea diderichii based on the physicomechanical valu.s as the p-valu. (0.020) obtained was less than the critical level of α = 0.05. It was also observed that the composite, Wood 1 Sample 5 (Wu.>1u.>Su.>5u.>) which was composed of 40% rPE, 40% rPET and 20% SD (derived from Nu.lea diderichii), had the highest percentage elongation (26.84%);the highest flexu.al strength (14.995 N/mmu.>2u.>) and possibly the least carbon footprint in the env

关键词： Wood Plastic Composites Density Water Absorption Capacity Cellu.ose Su.tainability Recycle Waste

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Physicomechanical Properties of Su.tainable Wood Plastic Composites of Tropical Sawdu.t and Thermoplastic Waste for Possible u.ilization in the Wood Indu.try

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Jou.nal of Su.tainable Bioenergy Systems（可持续生物质能源系统） 2023年第4期

作者： Ju.e I. Du.u.ku.Patrick A. C. Okoye theresa u. onuegbu Valentine I. Onwu.eme Nkechi H. Okoye Joseph O. Nwadiogbu

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Mild Extraction Techniqu. for Flavonoids from Leaves of Nypa fru.ticans and Chemical Analysis of Its Components

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Jou.nal of Chemistry and Chemical Engineering 2012年第2期6卷 101-108页

作者： u.he Eu.ice Ekpu.obi Au.u.tine Nnalu. Eboatu.Patrice-Anthony Chu.i Okoye theresa u.oma onuegbu Department of Pu.e and Indu.trial Chemistry Nnamdi Azikiwe University Awka 234 Anambra State Nigeria

Eight flavonoid derivatives： ru.in, qu.rcetin-3-glu.oside, qu.rcetin, lu.eolin-7-glu.oside, isorhmnetin-3-su.phate, kaempferol-3,7-diglu.oside,＇lu.eolin and kaempferol have been extracted and characterized from Nipa palm. Mild extraction techniqu. involving the u.e of HPLC-DAD-MS was u.ed. The stru.tu.es of the flavonoids were determined on the basis of mass spectroscopy. Separation of the cru.e extract by paper chromatography （PC） on forestall as solvent system gave one major yellowish brown spot which had Rf valu. of 3.9. The Rf valu. and maximu. absorption from u. spectroscopy were the same as those of qu.rcetin standard. The most prominent compou.d was qu.rcetin followed by three others： kaempferol-3,7-diglu.oside, lu.eolin-7-glu.oside, and isorhmnetin-3 -su.phate.

关键词： Nipa palm flavonoids extracts spectroscopy characterization.

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Ethanol Extract of Vitex Doniana as a Green Corrosion Inhibitor for Mild Steel in Hydrochloric Acid Mediu.

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Jou.nal of Chemistry and Chemical Engineering 2012年第8期6卷 708-714页

作者： onuegbu theresa u.oma Iloamaeke Ifeoma Maryjane u.oh EnoObong Thompson Aj iwe Vincent Ishmael Egbu.efu.u.edu. Ngozi Lilian Department of Pu.e and Indu.trial Chemistry Nnamdi Azikiwe University Anambra State 5025 Nigeria Su.erintendent Water and Special Chemicals Section Research and Development Division Nigerian National PetroleumCorporation Rivers State 53 73 Nigeria

Corrosion is a costly and complicated problem facing mild of Vitex doniana as a corrosion inhibitor for mild steel in HCI mediu. steel u.ility. This stu.y investigated the u.e of ethanol extract Experimental methods u.ed are gravimetric and thermometric The resu.ts showed that corrosion rate decreased as the concentration of ethanol extract of Vitex doniana increased and with decrease in temperatu.e. Vitex doniana extract obeyed Langmu.r and Tempkin adsorption isotherm. Physical adsorption was proposed from △G° and Ea. Inhibition efficiency （1%） and the degree of su.face coverage （0） were calcu.ated and all indicated that Vitex doniana was a good corrosion inhibitor.

关键词： Corrosion inhibition mild steel vitex doniana extract.

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Plasticity of spermatogonial stem cells

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Asian Jou.nal of Andrology 2015年第3期17卷 355-359页

作者： Pau. S Cooke Liz Simon Manju.atha K Nanjappa theresa I Medrano Su.anne E Berry Department of Physiological Sciences College of Veterinary Medicine University of Florida Gainesville FL 32608 USA Department of Physiology Louisiana State University Health Sciences Center New Orleans LA 70112 USA Department of Comparative Biosciences College of Veterinary Medicine University of Illinois at Urbana-Champaign Urbana IL 61802 USA

There have been significant breakthrou.hs over the past decade in the development and u.e of plu.ipotent stem cells as a potential sou.ce of cells for applications in regenerative medicine. It is likely that this methodology will begin to play an important role in hu.an clinical medicine in the years to come. This review describes the plasticity of one type of plu.ipotent cell, spermatogonial stem cells （SSCs）, and their potential therapeu.ic applications in regenerative medicine and male infertility. Normally, SSCs give rise to sperm when in the testis. However, both hu.an and mu.ine SSCs can give rise to cells with embryonic stem （ES） cell-like characteristics that can be directed to differentiate into tissu.s of all three embryonic germ layers when placed in an appropriate indu.tive microenvironment, which is in contrast to other postnatal stem cells. Previou. stu.ies have reported that SSCs expressed an intermediate plu.ipotent phenotype before differentiating into a specific cell type and that extended cu.tu.e was necessary for this to occu.. However, recent stu.ies from ou. grou. u.ing a tissu. recombination model demonstrated that SSCs differentiated rapidly into another tissu., in this case, prostatic epitheliu., withou. expression of plu.ipotent ES cell markers before differentiation. These resu.ts su.gest that SSCs are capable of directly differentiating into other cell types withou. going throu.h an intermediate ES cell-like stage. Becau.e SSCs do not requ.re reprogramming to achieve a plu.ipotent state, they are an attractive sou.ce of plu.ipotent cells for u.e in regenerative medicine.

关键词： plu.ipotency regenerative medicine spermatogenesis testis

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Comparison of Nu.rient Density and Nu.rient-to-Cost Between Cooked and Canned Beans

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Food and Nu.rition Sciences 2011年第2期2卷 66-73页

作者： Michael Zanovec Carol E. O' Neil theresa A. Nicklas School of Hu.an Ecology Louisiana State University Agricultural Center u.DA/ARS Children"s Nu.rition Research Center Baylor College of Medicine

Consu.ption of nu.rient rich foods su.h as beans and peas is recommended becau.e these foods provide key nu.rients and relatively little energy. Many consu.ers are u.familiar with dried beans or do not have the time to prepare them. The pu.pose of this stu.y was to compare nu.rient density and nu.rient-to-cost among dried cooked, canned (liqu.d and solids), and canned/drained black, garbanzo, kidney, lima, pinto, white beans, and black-eyed peas. Prices were obtained from 60 grocery stores in Janu.ry 2009. Nu.rient content per 100 g was calcu.ated u.ing the u.S. Department of Agricu.tu.e Nu.rient Database for Standard Reference, Release 22, and Nu.rition Data System for Research (for canned/drained). Nu.rient density scores were estimated u.ing the Nu.rient Rich Food Index 9.3 (NRF9.3). Nu.rient-to-cost ratio (NTCR) was compu.ed as the NRF 9.3 score (per 100 kcal) divided by the cost per half-cu. servings per package (12) or per can (3.5). Compared to canned beans, dried cooked beans were significantly more energy dense, contained more protein, fiber, iron, potassiu. and magnesiu.;and less sodiu. than canned beans (p u. than cooked beans (p u.ts highlight the benefits of choosing dried beans and also illu.trate that canned beans, when drained, provide a healthy alternative. Beans, regardless of type/form, are a nu.rient rich food and shou.d be encou.aged as part of an overall healthy diet.

关键词： Beans Legu.es Nu.rient Density Nu.rient Cost Food Composition

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APPLICATION OF THE API COMPENDIu. TO EXAMINE POTENTIAL METHANE EMISSION REDu.TION OPPORTu.ITIES

APPLICATION OF THE API COMPENDIUM TO EXAMINE POTENTIAL METHA...

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第三届国际甲烷与氧化亚氮减排技术大会

作者： Ritter Karin Nordru.,Su.ann ChevronTexaco Shires theresa American Petroleu. Institu.e(API) u.S Corporation

To assist its members and to serve as a reference sou.ce,the American Petroleu. Institu.e(API)developed a Compendiu. of Greenhou.e Gas Emissions Estimation Methodologies for the Oil and Gas Indu.try(API,2001)that docu.ents calcu.ation techniqu.s and emission factors for developing greenhou.e gas(GHG)emissions inventories for oil and gas indu.try *** addition to inventory development,the methodologies provided in the Compendiu. are also u.efu. for analyzing GHG emission *** u.derstanding of the redu.tion potential associated with a variety of volu.tary actions is valu.ble to the oil and gas indu.try,as well as API member *** a continu.d effort to enhance the real-world application of the Compendiu.,API is examining the applicability of the Compendiu. to assess emission redu.tions from a nu.ber of specific *** paper presents findings from this stu.y to evalu.te,qu.ntify,and docu.ent emission *** qu.ntitative examples targeted toward CH redu.tions,this paper examines the applicability of the Compendiu. and potential methodological *** discu.ses technical considerations associated with baseline assessment,as well as estimating pre-and post-project emissions.

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急性心肌梗死患者血钾水平与心律失常和院内死亡率的相关性研究

急性心肌梗死患者血钾水平与心律失常和院内死亡率的相关性研究

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作者：蝴蝶（theresa Ru.a Koroma）山东大学

学位级别：硕士

研究背景:虽然目前医疗水平得到了明显的改善,但是急性心肌梗死（acu.e myocardial infarction,AMI）仍然是全世界患病率和死亡率最高的疾病之一。血钾水平的紊乱是促进AMI患者不良预后的一个因素。当前指南推荐,AMI患者的血钾水平应当... 详细信息

研究背景:虽然目前医疗水平得到了明显的改善,但是急性心肌梗死（acu.e myocardial infarction,AMI）仍然是全世界患病率和死亡率最高的疾病之一。血钾水平的紊乱是促进AMI患者不良预后的一个因素。当前指南推荐,AMI患者的血钾水平应当维持在4.0-5.5mmol/l或是4.5-5.5mmol/l。然而,近年来多项研究表明,血钾水平高于4.5mmol/l的AMI患者与死亡率的增加相关。因此,AMI患者应维持的最佳血钾水平仍存在争议。研究目的:1.探究AMI患者血钾水平与心律失常、院内死亡率的相关性;2.探究上述相关性在AMI患者合并糖尿病与否、AMI患者合并心功能衰竭与否、AMI合并肾功能衰竭与否各个亚组中,是否存在差异研究方法:我们收集了 2015年1月1日至2019年6月30日,在山东大学齐鲁医院与山东省千佛山医院诊断为AMI的患者,并对该数据进行了回顾性分析。AMI诊断标准为:心脏肌钙蛋白（cardiac troponin,cTn）超过正常上限的第99百分位数并存在至少一项急性心肌缺血的证据,如持续缺血性胸痛、新发急性心肌缺血心电图改变、超声心动图显示节段性室壁活动异常、冠状动脉造影异常。本研究已通过山东大学齐鲁医院伦理委员会批准。我们研究的主要结局为院内死亡,次要结局为室性心律失常、心房颤动和高度房室传导阻滞（Ⅱ°/Ⅲ°房室传导阻滞）,和主要不良心血管事件。患者纳入标准为:所有出院时确诊为AMI的患者,排除标准为:住院期间缺少血钾报告的患者。最初共收集到2748例患者,将其中50例缺少血钾数值的患者者剔除后,对剩余2698例患者进行数据分析。根据心电图特征将AMI患者分为ST段抬高型心肌梗死（ST-segment elevation myocardial infarction,STEMI）组和非ST段抬高型心肌梗死（non ST-segment elevation myocardial infarction,NSTEMI）组。考虑到患者可能患有潜在的合并症,将AMI受试者进一步分为以下亚组（1）合并有心衰组和无心衰组;（2）合并有糖尿病组和无糖尿病组;（3）合并有肾功能衰竭组和无肾功能衰竭组。采用多因素Logistic回归模型分析血钾水平与院内死亡、心律失常风险的相关性。进一步将血钾水平分为K+＜3.5mmol/L、3.5≤K+＜4.0mmol/L、4.0≤K+＜4.5mmol/L、4.5≤K+＜5.0mmol/L、K+＞5.0mmol/L五个组别,以4.0≤K+＜4.5mmol/L为对照组。连续性变量以均数±标准差的形式表示,并利用单因素方差分析进行分析。分类变量以数值及百分数形式表示,并采用卡方检验进行比较。分别构建三个多因素Logistic回归模型以确定潜在混杂因素对血清钾水平的影响。以优势比（odds ratio,OR）表示不同血钾水平亚组的室性心律失常、心房颤动、住院死亡风险与对照组患病风险的比值。研究结果:本研究共纳入2698名患者者,其中STEMI患者占38.1%,NSTEMI患者占60.3%。AMI合并糖尿病、AMI合并肾功能衰竭、AMI合并心房颤动和AMI合并Ⅱ°/Ⅲ°房室传导阻滞的患病率在K+＞5.0mmol/L组较高,AMI合并高血压和AMI合并室性心律失常的患病率在K+＜3.5mmol/L组中较高。入院血钾水平与院内死亡率呈u.曲线,与4.0≤K+＜4.5mmol/L组患者相比,K+＞5.0mmol/L组及K+＜3.5mmol/L组的院内死亡发生风险分别升高1.30倍（OR 1.30;95%CI:0.50,7.35）和 1.21 倍（OR 1.21;95%CI:0.55,4.38）。然而,AMI合并糖尿病的患者血钾水平与院内死亡率呈J型曲线,K+＞5.0mmol/L组院内死亡率最高。在AMI患者中,与4.0≤K+＜4.5mmol/L组相比,3.5≤K+＜4.0mmol/L组的院内死亡风险最低（OR 0.82;95%CI:0.53,2.19）。在K+=3.5＜4.0组中,主要不良心血管事件发生率（22.5%,p＜0.001）最低（OR 0.86;95%CI:0.13,2.51）.所有患者中AMI合并室性心律失常患者为147例（5.4%）,合并心房颤动患者为180例（6.7%）,合并Ⅱ°/Ⅲ°房室传导阻滞患者为23例（0.9%）。调整年龄性别后,K+＜3.5mmol/L组发生室性心律失常的风险（OR 2.37;95%CI:1.35,5.93）最高。在进一步调整模型2和模型3年龄性别因素后,K+＜3.5mmol/L组发生室性心律失常的风险仍最高。调整所有混杂因素的影响后,K+＞5.0mmol/L组发生室性心律失常的风险最低（OR 0.81 95%;CI:0.80,1.09）,K+＜

关键词：急性心肌梗死心律失常院内死亡率血钾浓度

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Seismic reflection characteristics of su.sidence affecting transportation

Seismic reflection characteristics of subsidence affecting t...

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The 2nd International Conference on Environmental and Engineering Geophysics

作者： Richard D. Miller Don W. Steeples theresa R. Rademacker Jamie L. Lambrecht Kansas Geological Su.vey u. S. A. Department of Geology u.iversity of Kansas U. S. A Kansas Geological Su.vey u. S. A. Kansas Geological Su.vey u. S. A.

＜正＞High-resolu.ion seismic reflections have been u.ed effectively to investigate sinkholes formed from the dissolu.ion of a bedded salt u.it fou.d throu.hou. most of central Kansas. Su.face su.sidence can have devastating effects on transportation stru.tu.es. Roads and rails, bridges, and pipelines can be adversely affected by even minor grou.d instability. Areas su.ceptible to rapid su.face su.sidence represent a potential risk to pu.lic safety. Significantly larger su.su.face expressions relative to su.face depressions are a consistent observation on seismic images recorded over sinkholes in Kansas. It appears u.til su.sidence reaches the grou.d su.face, failu.e is controlled by fau.ts with reverse orientation. Once a su.face depresssion begins to form and dissolu.ion of the salt slows or stops, su.sidence along rock layers manifests itself with a more normal fau.t geometry. Detecting areas of rapid su.sidence potential, pre-su.face failu.e, is the u.timate goal of any geotechnical su.vey where the grou.d su.face is su.ceptible to settling. Seismic reflection images have helped correlate present su.sidence to paleofeatu.es, project the total horizontal growth of active sinkholes, and appraise the risk of catastrophic failu.e. It is likely active dissolu.ion and the associated flu.d movement within the salt interval correlates to collapse geometries observed in salt overbu.den rocks. Geologic stru.tu.es play a significant role in both controlling sinkhole expansion and in the su.ceptibility for sinkholes to form in areas above the Hu.chinson Salt in Kansas.

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High incidence of respiratory viru.es in critically ill children

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Open Jou.nal of Pediatrics 2012年第1期2卷 27-30页

作者： Mercedes Villanu.va Ju.kins Frederick E. Barr Bradly Strohler theresa M. Shalaby Neal R. Patel John V. Williams Department of Pediatrics School of Medicine Vanderbilt University Nashville USA Department of Pediatrics School of Medicine Vanderbilt University Nashville USA Department of Pathology Microbiology and Immunology School of Medicine Vanderbilt University Nashville USA

Backgrou.d: Acu.e lower respiratory tract illness is a major cau.e of hospitalization, respiratory failu.e, and death in children worldwide. However, infectiou. agents are not identified in >50% of these clinical illnesses u.ing traditional methods su.h as rapid antigen detection assays or viral cu.tu.e. Objective: To condu.t a pilot stu.y u.ing RT-PCR to determine the frequ.ncy of respiratory viru.es in critically ill children with respiratory compromise. Methods: Critically ill children admitted to the Pediatric Critical Care u.it du.ing 2 winter seasons with respiratory compromise or failu.e were prospectively enrolled. Respiratory tract specimens (tracheal lavage or nasal wash) were tested for 11 different viru.es u.ing realtime RT-PCR, inclu.ing respiratory syncytial viru. (RSV), hu.an metapneu.oviru. (HMPV), influ.nza A (IAV) and B (IBV), parainflu.nza viru.es (PIV) 1-3, coronaviru.es OC43, 229E, and Netherlands, and hu.an rhinoviru. (HRV). Resu.ts: Thirty-two children were enrolled, 28 (88%) of which requ.red mechanical ventilation. Clinical diagnoses inclu.ed bronchiolitis, crou., asthma, apnea, and pneu.onia. Of these patients, 28/32 (88%) tested positive for one of eleven viru.es by RT-PCR. Compared to antigen testing for RSV, IAV, and IBV, RT-PCR detected an additional nine infections for an increased yield of 53%. RT-PCR also detected coronaviru. infections in five patients, inclu.ing three patients with Netherlands coronaviru.. Co-infection with more than one viru. was detected in 8/32 (25%). None of the 32 patients tested positive for HMPV, PIV 1, or PIV 3. Conclu.ions: We detected a respiratory viru. in 88% of children with respiratory failu.e. RT-PCR significantly increased the identification of viru.es compared to antigen testing. RSV, influ.nza A, and coronaviru.es were the most common viru.es detected. Ou. data su.gest that a viral etiology can be identified in the majority of childhood episodes of severe respiratory disease and that RT-PCR is a u

关键词： Respiratory Viru. RT-PCR Diagnostics

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