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Quantification of changes in zero valent iron morphology using X-ray computed tomography

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Journal of Environmental Sciences 2013年第11期25卷 2344-2351页

作者： Ping Luo elizabeth H.Bailey Sacha J.Mooney Division of Agricultural and Environmental Sciences School of Biosciences University of Nottingham Sutton Bonington CampusSutton Bonington

Morphological changes within the porous architecture of laboratory scale zero valent iron （ZVI） permeable reactive barriers （PRBs）, after exposure to different groundwater conditions, have been quantified experimentally for different ZVI/sand ratios （10%, 50% and 100%, W/W） with the aim of inferring porosity changes in field barriers. Column studies were conducted to simulate interaction with different water chemistries, a synthetic groundwater, acidic drainage and deionised （DI） water as control. Morphological changes, in terms of pore size and distribution, were measured using X-ray computed tomography （CT）. CT image analysis revealed significant morphological changes in columns treated with different water chemistries. For example, 100% ZVI （W/W） columns had a higher frequency of small pores （0.6 mm） was observed in ZVI grains reacted with typical groundwater, resulting in a porosity of 27%, compared to 32% when exposed to DI water. In comparison, ZVI grains treated with the acidic drainage had higher porosity （44%） and larger average pore size （2.8 mm）. 10% ZVI PRB barrier material had the highest mean porosity （56%） after exposure to any water chemistry whilst 100% ZVI （W/W） columns always had the lowest （34%） with the 50% ZVI （W/W） in between （40%）. These results agree with previously published PRB field data and simultaneously conducted geochemical monitoring and mass balance calculation, indicating that both the geochemical and hydraulic environment of the PRB play an important role in determining barrier lifespan. This study suggests that X-ray CT image analysis is a powerful tool for studying the detailed inter pores between ZVI grains within PRBs.

关键词： porosity change X-ray computer tomography mass balance permeable reactive barrier zero valent iron acidic drainage typical groundwater pore-clogging

RIP1 （ROP Interactive Partner 1）/ICR1 Marks Pollen Germination Sites and May Act in the ROP1 Pathway in the Control of Polarized Pollen Growth

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Molecular Plant 2008年第6期1卷 1021-1035页

作者： Shundai Li Ying Gu An Yan elizabeth Lord Zhen-Biao Yang Center for Plant Cell Biology Institute of Integrative Genome Biology and Department of Botany and Plant Sciences University of California Riverside CA92521 USA Present address: Energy Biosciences Institute University of California Berkeley Berkeley CA 94720 USA

Rho family small GTPases are universal signaling switches in the control of cell polarity in eukaryotic cells. Their polar distribution to the cell cortex is critical for the execution of their functions, yet the mechanism for this distribution is poorly understood. Using a yeast two-hybrid method, we identified RIP1 （ROP interactive partner 1）, which belongs to a family of five members of novel proteins that share a C-terminal region that interacts with ROP. When expressed in Arabidopsis pollen, green fluorescence protein GFP-tagged RIP1 was localized to the nucleus of mature pollen. When pollen grains were hydrated in germination medium, GFP-RIP1 switched from the nucleus to the cell cortex at the future pollen germination site and was maintained in the apical cortex of germinating pollen and growing pollen tubes. RIP1 was found to interact with ROP1 in pollen tubes, and the cortical RIP1 localization was influenced by the activity of ROP1. Overexpression of RIP1 induced growth depolarization in pollen tubes, a phenotype similar to that induced by ROP1 overexpression. Interestingly, RIP1 overexpression enhanced GFP-ROP1 recruitment to the plasma membrane （PM） of pollen tubes. Based on these observations, we hypothesize that RIP1 is involved in the positive feedback regulation of ROP1 localization to the PM, leading to the establishment of a polar site for pollen germination and pollen tube growth.

关键词： RIP1 Pollen Germination Polarized Pollen Growth Control

Can a multistage approach improve individual tree mortality predictions across the complex mixed-species and managed forests of eastern North America?

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Forest Ecosystems 2023年第1期10卷 21-30页

作者： Cen Chen John Kershaw Jr Aaron Weiskittel elizabeth McGarrigle Center for Research on Sustainable Forests University of MaineOronoME04469USA Faculty of Forestry&Environmental Management University of New BrunswickFrederictonNBE3B 5A3Canada Nova Scotia department of Natural Resources HalifaxNSB3J 3M8Canada

Tree mortality plays a fundamental role in the dynamics of forest ecosystems,yet it is one of the most difficult phenomena to accurately *** modeling strategies have been developed to improve individual tree mortality *** less explored strategy is the use of a multistage modeling *** improvements from this approach have remained largely *** this study,we developed a novel multistage approach and compared its performance in individual tree mortality predictions with a more conventional approach using an identical individual tree mortality model *** permanent plot data(n=9442)covering the Acadian Region of North America and over multiple decades(1965–2014)were used in this *** results indicated that the model behavior with the multistage approach better depicted the observed mortality and showed a notable improvement over the conventional *** difference between the observed and predicted numbers of dead trees using the multistage approach was much smaller when compared with the conventional *** addition,tree survival probabilities predicted by the multistage approach generally were not significantly different from the observations,whereas the conventional approach consistently underestimated mortality across species and overestimated tree survival probabilities over the large range of DBH in the *** new multistage approach also predictions of zero mortality in individual plots,a result not possible in conventional ***,the new approach was more tolerant of modeling errors because it based estimates on ranked tree mortality rather than error-prone predicted ***,this new multistage approach deserves to be considered and tested in future studies.

关键词： Tree mortality modeling Mortality disaggregation Mixed effect model Annualization Mixed forests

Operable gastro-oesophageal junctional adenocarcinoma: Where to next?

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World Journal of Gastrointestinal Oncology 2014年第6期6卷 145-155页

作者： elizabeth C Smyth David Cunningham department of Gastrointestinal Oncology Royal Marsden Hospital

Oesophageal junctional adenocarcinoma is a challeng-ing and increasingly common disease. Optimisation ofpre-operative staging and consolidation of surgery inlarge volume centres have improved outcomes, howev-er the preferred adjunctive treatment approach remainsa matter of debate. This review examines the benefitsof neoadjuvant, peri-operative, and post-operative che-motherapy and chemoradiotherapy in this setting in anattempt to reach an evidence based conclusion. Recentfindings relating to the molecular characterisation ofoesophagogastric cancer and their impact on therapeu-tics are explored, in addition to the potential benefitsof fluoro-deoxyglucose positron emission tomography(FDG-PET) directed therapy. Finally, efforts to decreasethe incidence of junctional adenocarcinoma using earlyintervention in Barrett's oesophagus are discussed,including the roles of screening, endoscopic mucosalresection, ablative therapies and chemoprevention.

关键词： Oesophageal adenocarcinoma Junctional adenocarcinoma Gastric adenocarcinoma Peri-operative chemotherapy Pre-operative chemoradiotherapy Molecular profiling Fluoro-deoxyglucose-positron emission tomography Barrett's oesophagus Chemoprevention

Emerging molecular targets and therapy for cholangiocarcinoma

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World Journal of Gastrointestinal Oncology 2017年第7期9卷 268-280页

作者： Hamzeh Kayhanian elizabeth C Smyth Chiara Braconi department of Gastrointestinal Oncology Royal Marsden Hospital London and Surrey SM2 5PT Institute of Cancer Research London and Surrey SM2 5PT

Cholangiocarcinoma(CCA) is a rare cancer arising from the biliary tree with a poor prognosis and limited therapeutic options. Recent large scale molecular characterisation studies have identified recurrent genetic alterations in CCA which may be amenable to therapeutic targeting. In this review we explore the genomic landscape of CCA and examine results from trials of molecularly targeted agents and immunotherapy in this disease. Challenges in CCA diagnosis, treatment and trial design are discussed and we reflect on future directions which may lead to improved outcomes for CCA patients.

关键词： Cholangiocarcinoma Biliary tract cancer Targeted therapy immunotherapy Mutation Molecular Microenvironment Stroma MiRNA

Does pH of tyrode solution modify glucose and electrolyte jejunal absorption in rats?

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Journal of Biophysical Chemistry 2012年第2期3卷 127-131页

作者： elizabeth Lage Borges Marcelo de Pinho Viana departamento de Fisiologia e Biofísica Instituto de Ciências Biológicas Universidade Federal de Minas Gerais Belo Horizonte Brazil

Studies have shown that glucose is able to decrease the pH of the surface epithelium jejunal preparations when added in vitro and the existence of a high concentration of protons in the immediate area of the mucosa could be of considerable significance for absorption of electrolytes. The aim of this study is to assess whether the change in pH of Tyrode (solution used for perfusion of the jejunum) interferes with the absorption of glucose and electrolytes. Male Wistar rats weighing 200 to 220 g (n = 6) were utilized. Jejunal absorption of glucose and electrolytes was investigated in rats. A Tyrode solution containing twice glucose, sodium and potassium concentration (pH 7.0, 7.4, 8.0 and 8.5) was infused through the jejunal loops during 40 minutes. The glucose absorption was not significantly affected by Tyrode. However, there was significantly decrease in sodium absorption at pH 7.0 and 8.5 (41.13 ± 2.79 and 41.37 ± 1.71, respectively, P de has no influence on glucose absorption. However, the major potassium uptake occurs at pH 8.0, while the absorption of sodium is impaired at pH 7.0 and 8.5.

关键词： Absorption pH Glucose Sodium Potassium Jejunum

Aging gracefully: social engagement joins exercise and enrichment as a key lifestyle factor in resistance to age-related cognitive decline

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Neural Regeneration Research 2019年第1期14卷 39-42页

作者： Tyler J.Dause elizabeth D.Kirby department of Psychology The Ohio State University department of Neuroscience The Ohio State University Chronic Brain Injury Program The Ohio State University

Cognitive impairment is a consequence of the normal aging process that effects many species, including humans and rodent models. decline in hippocampal memory function is especially prominent with age and often reduces quality of life. As the aging population expands, the need for interventional strategies to prevent cognitive decline has become more pressing. Fortunately, several major lifestyle factors have proven effective at combating hippocampal aging, the most well-known of which are environmental enrichment and exercise. While the evidence supporting the beneficial nature of these factors is substantial, a less well-understood factor may also contribute to healthy cognitive aging: social engagement. We review the evidence supporting the role of social engagement in preserving hippocampal function in old age. In elderly humans, high levels of social engagement correlate with better hippocampal function, yet there is a dearth of work to indicate a causative role. Existing rodent literature is also limited but has begun to provide causative evidence and establish candidate mechanisms. Summed together, while many unanswered questions remain, it is clear that social engagement is a viable lifestyle factor for preserving cognitive function in old age. Social integration across the lifespan warrants more investigation and more appreciation when designing living circumstances for the elderly.

关键词： aging age-related cognitive decline social engagement hippocampus cognitive enrichment exercise memory neurogenesis

VOLUME SEGMENTATION BY POST-PROCESSING DATA FROM SIMULATION OF SOLIDIFICATION IN THE METAL CASTING PROCESS

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International Journal of Modeling, Simulation, and Scientific Computing 2013年第S1期4卷 128-141页

作者： elizabeth JACOB M.MANOJ ROSCHEN SASIKUMAR Computational Modeling and Simulation Unit National Institute for Interdisciplinary Science and Technology Council of Scientific and Industrial Research Trivandrum–695019 India

In the process of interpreting simulation results,new post-processing techniques are *** work presents a post-processing method that analyzes the solidification pattern formed by simulation of the solidification process of molten metal in a mold to produce shaped *** generally involve numerical solutions of differential equations which are discretized by dividing the three-dimensional computational domain into small finite volume elements using a 3D *** locations of the grid points and values of the solidification time at these locations are used to divide the spatial data into 3D sections such that starting from a hotspot location within the section that has high solidification time,there is a gradient outwards with lower values of solidification *** section is assumed to be fed by one or more feeders that must freeze only after the section has solidified *** volume of a feeder can be determined from the volume of the section it is supposed to *** volume and surface area of sections are determined approximately to calculate feeder size and *** post-processing algorithm is a simulation-based quantitative approach to feeder design which in conventional foundry practice has been more of an art than *** is also general enough for use in other 3D segmentation applications.

关键词： Metal casting simulation solidification pattern volume segmentation feeder design.

Adult neural stem cell plasticity

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Neural Regeneration Research 2019年第2期14卷 256-257页

作者： elizabeth J.Sandquist Donald S.Sakaguchi department of Zoology Weber State University department of Genetics Development and Cell Biology Iowa State University Neuroscience Program Iowa State University Nanovaccine Institute Iowa State University

Stem cells derived from adult tissues have long been consideredmultipotent, able to differentiate into a limited number of cell typesfound in their tissue of origin. Embryonic stem cells, in contrast,are pluripotent, which may differentiate into almost all cell *** the ability to create induced pluripotent stem cells from somaticcells now available, the properties of multipotent stem cellsare being re-evaluated. If adult cells may be reverted to pluripotentstem cells, can multipotent stem cells also be manipulated towardspluripotency? Advancements in biotechnology now allow for bettermethods to investigate stem cell plasticity, such as the relativeinfluence of external versus intrinsic factors on cell fate. Recentstudies indicate that adult neural stem cells (NSCs) demonstrategreater plasticity under certain conditions, resulting in the derivationof a variety of cell types including muscle, hematopoietic, andepithelial cells. This suggests that NSCs may provide a potentialsource of rare cell types for clinical application as an alternative toembryonic stem cells. Producing rare cell types from NSCs ratherthan embryonic stem cells avoids the ethical issues surrounding theuse of this cell type. Further, NSCs may be an advantageous sourcecompared to induced pluripotent stem cells, which are difficult tocreate, expensive, and time-consuming to

关键词： cells stem cell NSCs types