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Spontaneous Imbibition of Water and Determination of Effective Contact Angles in the Eagle Ford Shale Formation Using Neutron Imaging

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Journal of Earth Science 2017年第5期28卷 874-887页

作者： Victoria H.DiStefano michael C.Cheshire Joanna mcFarlane Lindsay m.Kolbus Richard E.Hale Edmund Perfect Hassina Z.Bilheux Louis J.Santodonato Daniel S.Hussey David L.Jacobson Jacob m.Lamanna Philip R.Bingham Vitaliy Starchenko lawrence m.anovitz Physical Sciences Directorate Chemical Sciences Division Oak Ridge National Laboratory Bredesen Center University of Tennessee Energy & Environmental Sciences Directorate Energy & Transportation Sciences Division Oak Ridge National Laboratory Neutron Sciences Directorate Chemical and Engineering Materials Division Oak Ridge National Laboratory Nuclear Science & Engineering Directorate Reactor & Nuclear Systems Division Oak Ridge National Laboratory Department of Earth and Planetary Science University of Tennessee Neutron Sciences Directorate Instrument and Source Division Oak Ridge National Laboratory Physical measurement Laboratory National Institute of Standards and Technology Energy & Environmental Sciences Directorate Electrical & Electronics Systems Research DivisionOak Ridge National Laboratory

Understanding of fundamental processes and prediction of optimal parameters during the horizontal drilling and hydraulic fracturing process results in economically effective improvement of oil and natural gas extraction. Although modern analytical and computational models can capture fracture growth, there is a lack of experimental data on spontaneous imbibition and wettability in oil and gas reservoirs for the validation of further model development. In this work, we used neutron im- aging to measure the spontaneous imbibition of water into fractures of Eagle Ford shale with known geometries and fracture orientations. An analytical solution for a set of nonlinear second-order diffe- rential equations was applied to the measured imbibition data to determine effective contact angles. The analytical solution fit the measured imbibition data reasonably well and determined effective con- tact angles that were slightly higher than static contact angles due to effects of in-situ changes in veloci- ty, surface roughness, and heterogeneity of mineral surfaces on the fracture surface. Additionally, small fracture widths may have retarded imbibition and affected model fits, which suggests that aver- age fracture widths are not satisfactory for modeling imbibition in natural systems.

关键词： spontaneous imbibition effective contact angle neutron imaging Eagle Ford shale rock fractures.

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Vascularization in interconnected 3D printed Ti-6Al-4V foams with hydrogel matrix for biomedical bone replacement implants

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Science China materials 2018年第4期61卷 565-578页

作者： Victor L.Correa Kristine m.Garza lawrence E.murr Department of metallurgical Materials and Biomedical Engineering University of Texas at El Paso Department of Biological Sciences University of Texas at El Paso

Vascularization on newly implanted metal orthopedic implants has remained a challenge in the field of tissue engineering. To address this challenge, in this research,an interconnected foam structure of Ti-6 Al-4 V was microfabricated by electron beam melting(EBm) technique. The foam in question has a density of 1.77 g cm-3 with 60% porosity and a tensile strength of 18 GPa. An extracellular matrix based hydrogel was added as an aqueous matrix to the *** mimetic stress has been closely related to many wound healing biomedical applications as it increases survival and proliferation molecular signals. To that end, increased expression of hypoxia-inducible factor-1α(Hif-1α) and vascular endothelial growth factor(VEGF) in the aqueous hydrogel matrix was achieved by the addition of a hypoxia mimetic deferoxamine mesylate(DFm). In this study, the formation of an endothelial network was achieved in a hydrogel matrix in the presence of the before mentioned 3 D printed metal foam. Cellular viability, fluorescent microscopy and scanning electron microscopy imaging analysis demonstrate that pre-osteoblasts undergo proliferation and also attach efficiently to the foam when exposed to DFm. Human umbilical vascular endothelial cells(HUVECs) were grown in an extracellular matrix-like 3 D hydrogel and a hypoxia-like stress was achieved. This research demonstrates that pre-osteoblast cells undergo cell differentiation and increase the production of hydroxyapatite on exposure to the hypoxia mimetic molecule. This proposed approach encompasses an ideal prototype for a completely living implanted structure for future orthopedic implants.

关键词： Ti-6Al-4V electron beam melting angiogenesis deferoxamine mesylate hydrogel vascularization

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Strategies for creating living, additively manufactured, open-cellular metal and alloy implants by promoting osseointegration,osteoinduction and vascularization: An overview

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Journal of materials Science & Technology 2019年第2期35卷 231-241页

作者： lawrence E.murr Department of metallurgical Materials and Biomedical Engineering The University of Texas at El Paso W.m.Keck Center for 3D Innovation The University of Texas at El Paso

Additive manufacturing of porous, open-cellular metal or alloy implants, fabricated by laser or electron beam melting of a powder bed, is briefly reviewed in relation to optimizing biomechanical compatibility by assuring elastic(Young's) modulus matching of proximate bone, along with corresponding pore sizes assuring osseointegration and vasculature development and migration. In addition, associated, requisite compressive and fatigue strengths for such implants are described. Strategies for optimizing osteoblast(bone cell) development and osteoinduction as well as vascularization of tissue in 3 D scaffolds and tissue engineering constructs for bone repair are reviewed in relation to the biology of osteogenesis and neovascularization in bone, and the role of associated growth factors, bone morphogenic proteins, signaling molecules and the like. Prospects for infusing hydrogel/collagen matrices containing these cellular and protein components or surgically extracted intramedullary(bone marrow) concentrate/aspirate containing these biological and cell components into porous implants are discussed, as strategies for creating living implants, which over the long term would act as metal or alloy scaffolds.

关键词： Additive manufacturing Open cellular metal and alloy implants Electron beam melting Living implant strategies Vascularization Osseointegration Osteoinduction

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Frontiers of 3D Printing/Additive manufacturing: from Human Organs to Aircraft Fabrication

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Journal of materials Science & Technology 2016年第10期32卷 987-995页

作者： lawrence E.murr Department of metallurgical Materials and Biomedical Engineering The University of Texas at El Paso W.m.Keck Center for 3D Innovation The University of Texas at El Paso

It has been more than three decades since stereolithography began to emerge in various forms of additive manufacturing and 3D printing. Today these technologies are proliferating worldwide in various forms of advanced manufacturing. The largest segment of the 3D printing market today involves various polymer component fabrications, particularly complex structures not attainable by other manufacturing *** printer head systems have also been adapted to selectively print various speciated human cells and special molecules in attempts to construct human organs, beginning with skin and various tissue patches. These efforts are discussed along with metal and alloy fabrication of a variety of implant and bone replacement components by creating powder layers, which are selectively melted into complex forms（such as foams and other open-cellular structures） using laser and electron beams directed by CAD software. Efforts to create a ＂living implant＂ by bone ingrowth and eventual vascularization within these implants will be discussed briefly. Novel printer heads for direct metal droplet deposition as in other 3D printing systems are briefly described since these concepts will allow for the eventual fabrication of very large and complex products, including automotive and aerospace structures and components.

关键词： 3D printing/additive manufacturing Laser and electron beam melting Organ printing Organ and implant vascularization metal droplet printing

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Involvement of eicosanoids in the pathogenesis of pancreatic cancer: the roles of cyclooxygenase-2 and 5-lipoxygenase

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World Journal of Gastroenterology 2014年第31期20卷 10729-10739页

作者： lawrence m Knab Paul J Grippo David J Bentrem Department of Surgery Northwestern University Feinberg School of Medicine Robert H Lurie Comprehensive Cancer Center Northwestern University Jesse Brown VA medical Center

The interplay between inflammation and cancer progression is a growing area of research. A combination of clinical, epidemiological, and basic science investigations indicate that there is a relationship between inflammatory changes in the pancreas and neoplastic progression. Diets high in ω-6 polyunsaturated fatty acids provide increased substrate for arachidonic acid metabolism by cyclooxygenase-2 (COX-2) and 5-lipoxygenase (5-LOX) to form eicosanoids. These eicosanoids directly contribute to pancreatic cancer cell proliferation. Both COX-2 and 5-LOX are upregulated in multiple cancer types, including pancreatic cancer. In vitro studies using pancreatic cancer cell lines have demonstrated upregulation of COX-2 and 5-LOX at both the mRNA and protein levels. When COX-2 and 5-LOX are blocked via a variety of mechanisms, cancer cell proliferation is abrogated both in vitro and in vivo. The mechanism of COX-2 has been shown to include effects on apoptosis as well as angiogenesis. 5-LOX has been implicated in apoptosis. The use of COX-2 and 5-LOX inhibitors in clinical studies in patients with pancreatic cancer has been limited. Patient enrollment has been restricted to those with advanced disease which makes evaluation of these drugs as chemopreventive agents difficult. COX-2 and 5-LOX expression have been shown to be present during the early neoplastic changes of pancreatic cancer, well before progression to invasive disease. This indicates that the ideal role for these interventions is early in the disease process as preventive agents, perhaps in patients with chronic pancreatitis or hereditary pancreatitis.

关键词： Arachidonic acid Eicosanoid Cyclooxygenase-2 5-lipoxygenase Pancreatic cancer Inflammation

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morphology and orientation evolution of Cu_(6)Sn_(5)grains on(001)Cu and(011)Cu single crystal substrates under temperature gradient

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Journal of materials Science & Technology 2021年第36期95卷 29-39页

作者： Yuanyuan Qiao Xiaoying Liu Ning Zhao lawrence C m Wu Chunying Liu Haitao ma School of materials Science and Engineering Dalian University of TechnologyDalian 116024China Department of materials Science and Engineering City University of Hong KongHong Kong Special Administrative RegionChina

The morphology and orientation evolution of Cu_(6)Sn_(5)grains formed on(001)Cu and(011)Cu single crystal substrates under temperature gradient(TG)were *** initial orientated prism-type Cu_(6)Sn_(5)grains transformed to non-orientated scallop-type after isothermal ***,the Cu_(6)Sn_(5)grains with strong texture were revealed on cold end single crystal Cu substrates by imposing *** Cu_(6)Sn_(5)grains on(001)Cu grew along their c-axis parallel to the substrate and finally merged into one grain to form a fully ImC joint,while those on(011)Cu presented a strong texture and merged into a few dominant Cu_(6)Sn_(5)grains showing about 30°angle with the *** merging between neighboring Cu_(6)Sn_(5)grain pair was attributed to the rapid grain growth and grain boundary ***,a model was put forward to describe the merging *** different morphology and orientation evolutions of the Cu_(6)Sn_(5)grains on single crystal and polycrystal Cu substrates were revealed based on crystallographic relationship and Cu *** method for controlling the morphology and orientation of Cu_(6)Sn_(5)grains is really benefitial to solve the reliability problems caused by anisotropy in 3 D packaging.

关键词： 3D packaging Single crystal Cu Temperature gradient Orientation Disregistry Grain boundary migration

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Control of Cell Wall Extensibility during Pollen Tube Growth

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molecular Plant 2013年第4期6卷 998-1017页

作者： Peter K. Hepler Caleb m. Rounds lawrence J. Winship Biology Department University of Massachusetts Amherst MA 01003 USA School of Natural Science Hampshire College Amherst MA 01002 USA

In this review, we address the question of how the tip-growing pollen tube achieves its rapid rate of elongation while maintaining an intact cell wall. Although turgor is essential for growth to occur, the local expansion rate is controlled by local changes in the viscosity of the apical wall. We focus on several different structures and underly- ing processes that are thought to be major participants including exocytosis, the organization and activity of the actin cytoskeleton, calcium and proton physiology, and cellular energetics. We think that the actin cytoskeleton, in particular the apical cortical actin fringe, directs the flow of vesicles to the apical domain, where they fuse with the plasma mem- brane and contribute their contents to the expanding cell wall. While pH gradients, as generated by a proton-ATPase located on the plasma membrane along the side of the clear zone, may regulate rapid actin turnover and new polymeri- zation in the fringe, the tip-focused calcium gradient biases secretion towards the polar axis. The recent data showing that exocytosis of new wall material precedes and predicts the process of cell elongation provide support for the idea that the intussusception of newly secreted pectin contributes to decreases in apical wall viscosity and to cell expansion. Other prime factors will be the localization and activity of the enzyme pectin methyl-esterase, and the chelation of calcium by pectic acids. Finally, we acknowledge a role for reactive oxygen species in the control of wall viscosity.

关键词： cell expansion cell walls cytoskeleton dynamics polarity pollen development.

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The use of woods-run chips in filter socks to control erosion and sedimentation during petroleum development in the Appalachian Basin

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International Journal of Sediment Research 2019年第6期34卷 608-615页

作者： Shawn T.Grushecky Louis m.mcDonald lawrence Osborn West Virginia University Davis College of Agriculture Natural Resources and Design School of Natural Resources Appalachian Hardwood Center at West Virginia University School of Natural Resources Energy Land Management 3. Division of Plant and Soil SciencesEnvironmental Soil Chemistry and Soil Fertility

Filter socks frequently are used for erosion and sediment perimeter control during oil and gas development activities in the Appalachian Basin of the United *** specify the use of composted wood material for sock *** specification,as opposed to non-composted or fresh wood chips(woods-run),has created inefficiencies during well site *** than use fresh wood chips created during site construction,composted chips must be procured and used as filter sock media for erosion and sedimentation *** woods-run chips could be used as filter sock media instead of composted chips,there could be a significant reduction in energy/capital costs,truck traffic,and disposal *** primary objective of this research project was to compare the effectiveness of woodsrun material versus traditionally composted wood chips in controlling sediment transport as well as other chemical and physical parameters in a laboratory *** significant differences in pH(5.96 versus 6.02) or conductivity(0.029 dS/m versus 0.035 dS/m) were found in sediment laden water filtered through woods-run versus composted chips,***,chip particle sizes were outside the allowable limits for composted sock media,and moisture content also was outside the specified limits for woods-run ***(NO) concentrations were significantly higher in woods-run,while phosphorus(P) and potassium(K) concentrations were greater in composted chips;however none of the N,P,or K concentrations were above the regulatory ***,no difference in the filtering efficiency or time was found between woods-run and composted *** laboratory results indicate that current regulations allowing the use of woods-run chips in all but the highest quality watersheds is justified.

关键词： BmP Filter socks Petroleum exploration marcellus shale Wood chips

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Stigmatic exudate in the Annonaceae:Pollinator reward,pollen germination medium or extragynoecial compitum?

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Journal of Integrative Plant Biology 2017年第12期59卷 881-894页

作者： Jenny Y.Y.Lau Chun-Chiu Pang lawrence Ramsden Richard m.K.Saunders School of Biological Sciences the University of Hong KongPokfulam RoadHong KongChina

Although ＂dry-type＂ stigmas are widely re- garded as ancestral in angiosperms, the early-divergent family Annonaceae has copious stigmatic exudate. We evaluate three putative functions for this exudate： as a nutritive reward for pollinators; as a pollen germination medium; and as an extragynoecial compitum that enables pollen tube growth between carpels. Stigmatic exudate is fructose dominated （72.2%）, but with high levels of glucose and sucrose; the dominance of hexose sugars and the diversity of amino acids observed, including many that are essential for insects, support a nutritive role for pollinators. Sugar concentration in pre-receptive flowers is high （28.2%）, falling during the peak period of stigmatic receptivity （17.4%）, and then rising again toward the end of the pistillate phase （32.9%）. Pollen germination was highest in sugar concentrations 〈2%. Sugar concentrations during the peak pistillate phase therefore provide optimal osmolarity for pollen hydration and germination; subsequent changes in sugar concentration during anthesis reinforce protogyny （in which carpels mature before stamens）, enabling the retention of concentrated exudate into the staminate phase as a pollinator food reward without the possibility of pollen germination. Intercarpellary growth of pollen tubes was confirmed： the exudate therefore also functions as a suprastylar extragynoecial compitum, overcoming the limitations of apocarpy.

关键词： Stigmatic exudate in the Annonaceae pollen germination medium or extragynoecial compitum Pollinator reward

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Stress and immunological response of heifers divergently ranked for residual feed intake following an adrenocorticotropic hormone challenge

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Journal of Animal Science and Biotechnology 2018年第1期9卷 111-118页

作者： A.K.Kelly P.lawrence B.Earley D.A.Kenny m.mcGee School of Agriculture and Food Science College of Health and Agricultural SciencesUniversity College Dublin Livestock Systems Research Department Teagasc Animal&Grassland Research and Innovation CentreGrangeDunsanyCo. Animal and Bioscience Research Department Animal&Grassland Research and Innovation CentreTeagascDunsanyCo.

Background： When an animal is exposed to a stressor, metabolic rate, energy consumption and utilisation increase primarily through activation of the hypothalamic-pituitary-adrenal（HPA） axis. Changes to partitioning of energy by an animal are likely to influence the efficiency with which it is utilised. Therefore, this study aimed to determine the physiological stress response to an exogenous adrenocorticotropic hormone（ACTH） challenge in beef heifers divergently ranked on phenotypic residual feed intake（RFI）.Results： Data were collected on 34 Simmental weaning beef heifers the progeny of a well characterized and divergently bred RFI suckler beef herd. Residual feed intake was determined on each animal during the postweaning stage over a 91-day feed intake measurement period during which they were individually offered adlibitum grass silage and 2 kg of concentrate per head once daily. The 12 highest [0.34 kg Dm/d] and 12 lowest[-0.48 kg Dm/d] ranking animals on RFI were selected for use in this study. For the physiological stress challenge heifers（mean age 605 ± 13 d; mean BW 518 ± 31.4 kg） were fitted aseptically with indwelling jugular catheters to facilitate intensive blood collection. The response of the adrenal cortex to a standardised dose of ACTH（1.98 IU/kg metabolic BW^（0.75）） was examined. Serial blood samples were analysed for plasma cortisol, ACTH and haematology variables. Heifers differing in RFI did not differ（P = 0.59） in ACTH concentrations. Concentration of ACTH peaked（P 〈 0.001） in both RFI groups at 20 min post-ACTH administration, following which concentration declined to baseline levels by 150 min. Similarly, cortisol systemic profile peaked at 60 min and concentrations remained continuously elevated for 150 min. A RFI × time interaction was detected for cortisol concentrations（P = 0.06） with high RFI heifers had a greater cortisol response than Low RFI from 40 min to 150 min relative to ACTH administration. Cortisol response was positively assoc

关键词： Beef cattle Cortisol Feed efficiency Residual feed intake Stress response

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