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Isolation of Thermally Stable Cellulose Nanocrystals from Spent Coffee Grounds via Phosphoric Acid Hydrolysis

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Journal of Renewable Materials 2020年第2期8卷 187-203页

作者： Brody A.Frost E.Johan Foster virginia Tech Department of Materials Science and EngineeringMacromolecules Innovation Institute117 SurgeVirginia TechBlacksburgVA 24061USA

As the world's population exponentially grows,so does the need for the production of food,with cereal production growing annually from an estimated 1.0 billion to 2.5 billion tons within the last few *** rapid growth in food production results in an ever increasing amount of agricultural wastes,of which already occupies nearly 50%of the total landfill *** example,is the billions of dry tons of cellulose-containing spent coffee grounds disposed in landfills *** paper seeks to provide a method for isolating cellulose nanocrystals(CNCs)from spent coffee grounds,in order to recycle and utilize the cellulosic waste material which would otherwise have no *** have already been shown to have vast applications in the polymer engineering field,mainly utilized for their high strength to weight ratio for reinforcement of polymer-based nanocomposites.A successful method of purifying and hydrolyzing the spent coffee grounds in order to isolate usable CNCs was *** CNCs were then characterized using current techniques to determine important chemical and physical properties.A few crucial properties determined were aspect ratio of 12±3,crystallinity of 74.2%,surface charge density of(48.4±6.2)mM/kg cellulose,and the ability to successfully reinforce a polymer based *** characteristics compare well to other literature data and common commercial sources of CNCs.

关键词： Cellulose nanocrystals phosphoric acid hydrolysis agricultural waste industrial waste spent coffee grounds polymeric nanocomposites renewable cellulosic materials

Fitness and physiology of Adelges tsugae （Hemiptera： Adelgidae） in relation to the health of the eastern hemlock

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Insect Science 2016年第6期23卷 843-853页

作者： Anne C. Jones Donald E. Mullins Carlyle Brewster James P. Rhea Scott M. Salom Department of Entomology Pennsylvania State University PA 16801 Department of Entomology Virginia Tech Blacksburg VA 24061 USDA Forest Service Asheville NC 28804-3454 USA

The hemlock woolly adelgid, Adelges tsugae Annand is an invasive insect that frequently causes hemlock （Tsuga spp.） mortality in the eastern United states. Studies have shown that once healthy hemlocks become infested by the adelgid, nutrients are depleted from the tree, leading to both tree decline and a reduction of the adelgid population. Since A. tsugae is dependent on hemlock for nutrients, feeding on trees in poor health may affect the ability of the insect to obtain necessary nutrients and may consequently affect their physiological and population health. Trees were categorized as lightly or moderately impacted by A. tsugae based on quantitative and qualitative tree health measurements. Population health ofA. tsugae on each tree was determined by measuring insect density and peak mean fecundity; A. tsugae physiological health was determined by measuring insect biomass, total carbon, carbohydrate, total nitrogen, and amino nitrogen levels. Adelges tsugae from moderately impacted trees exhibited significantly greater fecundity than from lightly impacted trees. However, A. tsugae from lightly impacted hemlocks contained significantly greater levels of carbohydrates, total nitrogen, and amino nitrogen. While the results of the physiological analysis generally support our hypothesis that A. tsugae on lightly impacted trees are healthier than those on moderately impacted trees, this was not reflected in the population health measurements. Adelges tsugae egg health in response to tree health should be verified. This study provides the first examination of A. tsugae physiological health in relation to standard A. tsugae population health measures on hemlocks of different health levels.

关键词： Adelges tsugae carbohydrates fecundity nitrogen tree health Tsuga canadensis

Sexual and spatio-temporal variation of Lake Erie Walleye growth and maturity:A consequence of multiple impacting factors

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Aquaculture and Fisheries 2021年第4期6卷 400-413页

作者： Qiuyun Ma Yan Jiao Can Zhou Yiping Ren College of Fisheries Ocean University of ChinaQingdao266003China Department of Fish and Wildlife Conservation Virginia Polytechnic Institute and State UniversityBlacksburgVA24061USA Laboratory for Marine Fisheries Science and Food Production Processes Qingdao National Laboratory for Marine Science and TechnologyQingdao266000China College of Marine Sciences Shanghai Ocean UniversityShanghai201306China

Sexual and spatio-temporal variations have been observed in the life history parameters of many aquatic species and their causes have been related to harvesting pressure and environmental *** study aims to explore sexual,spatial and temporal variation in the growth and maturity through weight-at-length,length-at-age,and maturity-at-length relationships for Lake Erie Walleye(Sander vitreus)as a case to test some *** on whether harvest pressure and environmental changes(both local and global scale)caused the temporal changes of these life history traits were further *** and spatio-temporal variations in these life history traits were formulated using mixed-effects *** study found that geographic basin,sex,year and cohort all have substantial effects on the growth and maturity of Walleye based on survey data from 1989 to *** factors including water supply of Lake Erie,temperature,fishing pressure of Walleye,and global climate factors were found to correlate with the temporal variations of growth and maturity of Walleye *** findings should contribute to the future interpretation of Walleye life history variations and population *** methodology constructed in this study could be applied to explore the heterogeneity and impacting factors for other species in aquatic ecosystems.

关键词： Heterogeneity Growth and maturity Mixed effects model Great lakes Sander vitreus

Structural engineered living materials

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Nano Research 2024年第2期17卷 715-733页

作者： Yang Geng Zian Jia Ling Li 635 Prices Fork Road Department of Mechanical EngineeringVirginia Polytechnic Institute and State UniversityBlacksburg VA24061USA

Biological structural materials not only exhibit remarkable mechanical properties but also often embody dynamic characteristics such as environmental responsiveness,autonomy,and self-healing,which are difficult to achieve in conventional engineering *** merging materials science,synthetic biology,and other disciplines,engineered living materials(ELMs)provide a promising solution to combine living organisms with abiotic components,thus facilitating the construction of functional“living”*** natural materials,ELMs possess vitality and hold immense application potential in areas such as medicine,electronics,and construction,captivating increasing research attention *** an emerging branch of ELMs,structural ELMs aim to mimic living biological structural materials by achieving desired mechanical performance while maintaining important“living”*** we summarize the recent progress and provide our perspectives for this emerging research *** first summarize the superiority of structural ELMs by reviewing biological structural materials and biomimetic material design ***,we provide a systematic discussion on the definition and classifications of structural ELMs,their mechanical performance,and physiological ***,we summarize some critical challenges faced by structural ELMs and highlight directions of future *** hope this review article can provide a timely summary of the state of the art and relevant perspectives for future development of structural ELMs.

关键词： structural materials engineered living materials(ELMs) structural ELMs composites mechanical properties

Vlodeling information exchange between living and artificial cells

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Frontiers of Electrical and Electronic Engineering in China 2017年第1期5卷 76-89页

作者： Keith C.Heyde Mary Joe K. Rice Sung-Ho Paek Felicia Y. Scott Ruihua Zhang Warren C. Ruder Department of Mechanical Engineering Carnegie Mellon University Pittsburgh PA 15213 USA Department of Mechanical Engineering Virginia Polytechnic Institute and State University Blacksburg VA 24061 USA Department of Biological Systems Engi-neering Virginia Polytechnic Institute and State University Black sburg VA 24061 USA Department of Bioengineering University of Pittsburgh Pittsburgh PA 15219 USA

Background： The tools of synthetic biology have enabled researchers to explore multiple scientific phenomena by directly engineering signaling pathways within living cells and artificial protoeells. Here, we explored the potential for engineered living cells themselves to assemble signafing pathways for non-living protocells. This analysis serves as a preliminary investigation into a potential origin of processes that may be utilized by complex living systems. Specifically, we suggest that if living cells can be engineered to direct the assembly of genetic signaling pathways from genetic biomaterials in their environment, then insight can be gained into how naturally occurring living systems might behave similarly. Methods： To this end, we have modeled and simulated a system consisting of engineered cells that control the assembly of DNA monomers on microparticle scaffolds. These DNA monomers encode genetic circuits, and therefore, these microparticles can then be encapsulated with minimal transcription and translation systems to direct protocell phenotype. The modeled system relies on multiple previously established synthetic systems and then links these together to demonstrate system feasibility. Results： In this specific model, engineered cells are induced to synthesize biotin, which competes with biotinylated, circuit-encoding DNA monomers for an avidinized-microparticle scaffold. We demonstrate that multiple synthetic motifs can be controlled in this way and can be tuned by manipulating parameters such as inducer and DNA concentrations. Conclusions： We expect that this system will provide insight into the origin of living systems as well as serve as a tool for engineering living cells that assemble complex biomaterials in their environment.

关键词： synthetic biology artificial cells biotin microparticles

套细胞淋巴瘤石蜡包埋组织中细胞周期蛋白D1和t(11;14)易位检测的临床病理意义

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中华病理学杂志 2003年第4期32卷 337-341页

作者：水若鸿杨文涛孙孟红施达仁朱雄增复旦大学附属肿瘤医院病理科上海200032

目的　探讨套细胞淋巴瘤石蜡包埋组织中细胞周期蛋白 (cyclin)D1和t(11;14 )易位检测的可行性及其诊断和鉴别诊断价值。方法　收集套细胞淋巴瘤 36例 ,对照组小B细胞恶性淋巴瘤71例 ,均为石蜡包埋组织 ,运用免疫组织化学方法观察cyclinD... 详细信息

目的　探讨套细胞淋巴瘤石蜡包埋组织中细胞周期蛋白 (cyclin)D1和t(11;14 )易位检测的可行性及其诊断和鉴别诊断价值。方法　收集套细胞淋巴瘤 36例 ,对照组小B细胞恶性淋巴瘤71例 ,均为石蜡包埋组织 ,运用免疫组织化学方法观察cyclinD1的表达 ;用半巢式聚合酶链反应(PCR)法检测t(11;14 )易位 ,以看家基因 β 肌动蛋白 (actin)作为内对照检测DNA质量。结果　 (1)36例套细胞淋巴瘤中 2 6例 (72 2 % )表达cyclinD1,对照组无 1例表达。 (2 ) 10 7例标本中 10 1例(94 4 % )可检出 β actinDNA表达。 36例套细胞淋巴瘤中 2 2例检出t(11;14 )易位 ,对照组无 1例检出。去除 β actin和t(11;14 )易位均阴性 2例 ,套细胞淋巴瘤中t(11;14 )易位检出率为 6 4 7%。 (3)36例套细胞淋巴瘤中cyclinD1染色和 (或 )t(11;14 )易位检测阳性病例为 2 9例 ,总阳性率为 80 5 %。结论　套细胞淋巴瘤石蜡包埋组织中cyclinD1和t(11;14 )易位的检测具较高的特异性和可行性。

关键词：套细胞淋巴瘤石蜡包埋组织细胞周期蛋白 D1 t(11 14) 蛋白易位临床病理学