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Bio-Design and Manufacturing 2019年第3期2卷 172-180页

作者： Maha Alruwaili j.se A.Lopez kevin McCarthy Emmanuel G.Reynaud Brian j.Rodriguez Conway Institute of Biomolecular and Biomedical Research University College DublinDublinIreland School of Physics University College DublinDublinIreland School of Biomolecular and Biomedical Science University College DublinDublinIreland

Extrusion-based 3D bioprinting is a direct deposition approach used to create three-dimensional(3D)tissue scaffolds typically comprising *** are hydrated polymer networks that are chemically or physically ***,3D bioprinting is performed in air,despite the hydrated nature of hydrogels and the potential advantage of using a liquid phase to provide cross-linking and otherwise functionalize the *** this work,we print gelatin alginate hydrogels directly into a cross-linking solution of calcium chloride and investigate the influence of nozzle diameter,distance between nozzle and surface,calcium chloride concentration,and extrusion rate on the dimensions of the printed *** hydrogel layer height was generally found to increase with increasing extrusion rate and nozzle distance,according to the increased volume extruded and the available space,*** addition,the hydrogel width was generally found to increase with decreasing nozzle distance and cross-linking concentration corresponding to confinement-induced spreading and low crosslinking regimes,***/height ratios of^1 were generally achieved when the nozzle diameter and distance were comparable above a certain cross-linking *** these relationships,biocompatible 3D multilayer structures were successfully printed directly into calcium chloride cross-linking solution.

关键词： Gelatin alginate Hydrogel Additive manufacturing 3D printing 3D bioprinting Biomaterials Extrusion Bioplotting

A Comprehensive Overview of Skeletal Phenotypes Associated with Alterations in Wnt/β-catenin Signaling in Humans and Mice

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Bone Research 2013年第1期1卷 27-71页

作者： kevin A.Maupin Casey j.Droscha Bart O.Williams Program for Skeletal Pathobiology and Center for Tumor Metastasis Van Andel Research Institute333 Bostwick NEGrand RapidsMI 49503USA

The Wnt signaling pathway plays key roles in differentiation and development and alterations in this signaling pathway are causally associated with numerous human diseases. While several laboratories were examining roles for Wnt signaling in skeletal development during the 1990s, interest in the pathway rose exponentially when three key papers were published in 2001-2002. One report found that loss of the Wnt co-receptor, Low-density lipoprotein related protein-5 （LRPS）, was the underlying genetic cause of the syndrome Osteoporosis pseudoglioma （OPPG）. OPPG is characterized by early-onset osteoporosis causing increased susceptibility to debilitating fractures. Shortly thereafter, two groups reported that individuals carrying a specific point mutation in LRP5 （G171V） develop high-bone mass. Subsequent to this, the causative mechanisms for these observations heightened the need to understand the mechanisms by which Wnt signaling controlled bone development and homeostasis and encouraged significant investment from biotechnology and pharmaceutical companies to develop methods to activate Wnt signaling to increase bone mass to treat osteoporosis and other bone disease. In this review, we will briefly summarize the cellular mechanisms underlying Wnt signaling and discuss the observations related to OPPG and the high-bone mass disorders that heightened the appreciation of the role of Wnt signaling in normal bone development and homeostasis. We will then present a comprehensive overview of the core components of the pathway with an emphasis on the phenotypes associated with mice carrying genetically engineered mutations in these genes and clinical observations that further link alterations in the pathway to changes in human bone.

关键词： Wnt signaling mouse models Lrp5/Lrp6 -catenin skeletal phenotypes

Frontier orbitals and quasiparticle energy levels in ionic liquids

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npj.Computational Materials 2020年第1期6卷 441-447页

作者： j.han Matthias Kahk Ivar Kuusik Vambola Kisand kevin R.j.Lovelock j.hannes Lischner Department of Materials Imperial College LondonSouth KensingtonLondon SW72AZUK Institute of Physics University of TartuW.Ostwaldi 150411 TartuEstonia School of Chemistry Food and PharmacyUniversity of ReadingReading RG66DXUK Department of Physics and Department of Materials and the Thomas Young Centre for Theory and Simulation of Materials Imperial College LondonLondon SW72AZUK

Ionic liquids play an important role in many technological applications and a detailed understanding of their frontier molecular orbitals is required to optimize interfacial barriers,reactivity and stability with respect to electron inj.ction and *** this work,we calculate quasiparticle energy levels of ionic liquids using first-principles many-body perturbation theory within the GW approximation and compare our results to various mean-field approaches,including semilocal and hybrid density-functional theory and *** find that the mean-field results depend qualitatively and quantitatively on the treatment of exchange-correlation effects,while GW calculations produce results that are in excellent agreement with experimental photoelectron spectra of gas phase ion pairs and ionic *** results establish the GW approach as a valuable tool for understanding the electronic structures of ionic liquids.

关键词： liquids ionic quasi

Friction characteristics of confined inflatable structures

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Friction 2014年第4期2卷 365-390页

作者： Eduardo M.SOSA Gregory j.THOMPSON Ever j.BARBERO Subhadeep GHOSH kevin L.PEIL Department of Civil and Environmental Engineering West Virginia UniversityMorgantownWV 26506-6103USA Department of Mechanical and Aerospace Engineering West Virginia UniversityMorgantownWV 26506-6106USA

The availability of high‐strength fabrics and progress in the development of large‐scale inflatable technology made possible the creation of temporary and quickly deployable structures for protection of underground *** structures are relatively lightweight and portable,and can maintain the required rigidity while in *** benefits have prompted the development of inflatable structures for use in confined spaces,such as tunnels and large‐diameter pipes to act as barriers for containing flooding with minimal infrastructure *** work presents experimental results obtained from the evaluation of frictional characteristics of the fabric material that constitute the structural membrane of confined inflatable structures developed for protection of underground transportation tunnels and other large *** tests at coupon level and slippage tests in a reduced‐scale inflatable structure were performed in order to evaluate the frictional characteristics of Vectran *** at coupon level were performed to determine the friction coefficient for different surface types and *** with the reduced‐scale inflatable structure contributed to the understanding of the friction characteristics at system level when subj.cted to different pressurization or depressurization sequences designed to induce *** results indicate that friction coefficient values at coupon level are about 29 percent higher than values derived from reduced‐scale tests.

关键词： friction fabric materials inflatable structures slippage Vectran

Reduction of pro-inflammatory cytokines in rats following 7-day oral supplementation with a proprietary eggshell membrane-derived product

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Modern Research in Inflammation 2014年第1期3卷 19-25页

作者： kevin j. Ruff Dale P. DeVore ESM Technologies LLC Carthage USA Membrell LLC Carthage USA

NEM®?brand eggshell membrane is a novel dietary supplement that has been clinically shown to alleviate arthritis j.int pain and stiffness;however the mechanism of action is not well understood. Preliminary evidence from an?in vitro?study of?NEM®?indicated that the mechanism of action may be based on the reduction of pro-inflammatory cytokines.?In vivo?studies were therefore initiated to evaluate the effects of?NEM®?on pro-inflammatory and anti-inflammatory cytokines following oral administration in rats.?NEM®?was administered daily at doses of 6.13 mg/kg bw/day (Study 1), 10.0 mg/kg bw/day (Study 2), or at doses of 0 (control), 26.0 or 52.0 mg/kg bw/day (Study 3) by oral gavage for 7 consecutive days. Inflammation was induced in the Study 3 rats by intraperitoneal inj.ction of lipopolysaccharide. Changes in plasma cytokine levels from baseline following 7 days of oral supplementation with?NEM®?at 6.13 mg/kg bw/ day (Study 1) were statistically significant at Day 8 for IL-2, TIMP-1 and VEGF, at Day 21 for IL-10, and at Day 35 for MCP-1, MCP-3 and TIMP-1, and at 10.0 mg/kg bw/day (Study 2) were statistically significant at Day 8 for VEGF, at Day 21 for MIP-1β, MIP-2 and VEGF, and at Day 35 for MCP-3, MIP-1β, MIP-2 and VEGF. Changes in serum cytokine levels versus control at 26.0 mg/kg bw/day (Study 3) were statistically significant at all time-points for IL-1β?and at 1.5 hours for IL-10, and at 52.0 mg/kg bw/day (Study 3) were statistically significant at 1.5 hours for IFN-γ, IL-1β?and IL-10, and at 3 hours for IL-1β, and at 24 hours for IL-10. Taken together, these studies demonstrate that oral supplementation with?NEM®?can influence both early-phase pro-inflammatory cytokines like IL-1β?and TNF-α?(Study 3), as well as later-phase cytokines like MCP-1, MIP-1α?&?β, RANTES and VEGF (Study 1 & 2). These studies provide a possible basis for the mechanism of action of?NEM®?in vivo.

关键词： Pro-Inflammatory Cytokines Eggshell Membrane

Tree community composition,structure and diversity along an elevational gradient in an Andean forest of Northern Ecuador

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j.urnal of Mountain Science 2021年第9期18卷 2315-2327页

作者： j.MÉNEZ-PAZ Rosa WORTHY Samantha j.VALENCIA Renato PÉREZÁlvaro j.REYNOLDS Alex BARONE j.hn A BURGESS kevin S Laboratorio de Ecología de Plantas Escuela de Ciencias BiológicasFacultad de Ciencias Exactas y NaturalesPontificia Universidad Católica del EcuadorQuito 17-01-2184Ecuador Department of Biology College of Letters&SciencesColumbus State UniversityColumbusGeorgia 31907USA Herbario QCA Escuela de Ciencias BiológicasFacultad de Ciencias Exactas y NaturalesPontificia Universidad Católica del EcuadorQuito 17-01-2184Ecuador The Lovett School AtlantaGeorgia 30327USA

The Andean forests of northern Ecuador are known for their high levels of plant diversity relative to the area they ***,these forests grow on steep slopes that lead to dramatic habitat gradients across short *** extreme habitat gradients make the Andean forest ecosystem an excellent natural laboratory for understanding the effect of elevation on forest community diversity,structure and *** established 31 plots(50 m×5 m)which are divided between two elevational transects in the cloud forest of the Siempre Verde Reserve in the western foothills of the Andes Mountains of northern *** trees and tree ferns with a diameter at breast height(dbh)≥5 cm were measured and *** examined changes in community composition,structure,and diversity along and between the elevational transects and three elevational zones:low(2437–2700 m),middle(2756–3052 m),and high(3163–3334 m).We found four main trends associated with the elevational gradients at this site:(1)community composition differed between the two transects and among the three elevational zones according to N-MDS,ANOSIM,and percentage of shared species,with some species having limited distributions,(2)metrics of community structure showed opposite relationships with elevation,depending on the transect,with the only significant relationship(negative)found between basal area and elevation in the open trail transect,(3)alpha diversity,in general,peaked at mid-elevations,and(4)beta diversity consistently increased with distance between plots along *** complexity of changes in community composition,structure,and alpha diversity along elevation may be related to the heterogeneity of the environment on a local scale,such as topography,soil composition,and even human impact,or to dispersal limitation and should be investigated *** changes in community composition and the relatively high beta diversity found at this site exemplify the biological complexity of mon

关键词： Elevational gradient Cloud forest Andes Structure Composition Diversity

Current landscape in motoneuron regeneration and reconstruction for motor cranial nerve inj.ries

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Neural Regeneration Research 2020年第9期15卷 1639-1649页

作者： Yanj.n Xie kevin j.Schneider Syed A.Ali Norman D.Hogikyan Eva L.Feldman Michael j.Brenner Department of Otolaryngology-Head and Neck Surgery University of Michigan Medical SchoolAnn ArborMIUSA Department of Neurology University of Michigan Medical SchoolAnn ArborMIUSA

The intricate anatomy and physiology of cranial nerves have inspired clinicians and scientists to study their roles in the nervous system. Damage to motor cranial nerves may result from a variety of organic or iatrogenic insults and causes devastating functional impairment and disfigurement. Surgical innovations directed towards restoring function to inj.red motor cranial nerves and their associated organs have evolved to include nerve repair, grafting, substitution, and muscle transposition. In parallel with this progress, research on tissue-engineered constructs, development of bioelectrical interfaces, and modulation of the regenerative milieu through cellular, immunomodulatory, or neurotrophic mechanisms has proliferated to enhance the available repertoire of clinically applicable reconstructive options. Despite these advances, patients continue to suffer from functional limitations relating to inadequate cranial nerve regeneration, aberrant reinnervation, or incomplete recovery of neuromuscular function. These shortfalls have profound quality of life ramifications and provide an impetus to further elucidate mechanisms underlying cranial nerve denervation and to improve repair. In this review, we summarize the literature on reconstruction and regeneration of motor cranial nerves following various inj.ry patterns. We focus on seven cranial nerves with predominantly efferent functions and highlight shared patterns of inj.ries and clinical manifestations. We also present an overview of the existing reconstructive approaches, from facial reanimation, laryngeal reinnervation, to variations of interposition nerve grafts for reconstruction. We discuss ongoing endeavors to promote nerve regeneration and to suppress aberrant reinnervation and the development of synkinesis. Insights from these studies will shed light on recent progress and new horizons in understanding the biomechanics of peripheral nerve neurobiology, with emphasis on promising strategies for optimizing

关键词： axon degeneration cranial neuropathy facial nerve facial paralysis motoneuron nerve regeneration peripheral nerve recurrent laryngeal nerve synkinesis vocal fold paralysis

NOTES ON “MULTICRITERIA FUZZY DECISION-MAKING METHOD BASED ON A NOVEL ACCURACY FUNCTION UNDER INTERVAL-VALUED INTUITIONISTIC FUZZY ENVIRONMENT”

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j.urnal of Systems Science and Systems Engineering 2010年第4期19卷 504-508页

作者： kevin W. LI Zhouj.ng WANG Odette School of Business University of Windsor Windsor Ontario N9B 3P4 Canada School of Computer Science and Engineering Beihang University Beijing 100083 China Department of Automation Xiamen University Xiamen Fujian 361005 China

This note points outs the inappropriateness of an accuracy function introduced by Ye [Ye, j. （2009）. Multicriteria fuzzy decision-making method based on a novel accuracy function under interval-valued intuitionistic fuzzy environment. Expert Systems with Applications, 36 （3）： 6899-6902] and its misleading use for comparing two interval-valued intuitionistic fuzzy numbers.

关键词： Interval-valued intuitionistic fuzzy set accuracy function score function multicriteria decision-making

A strategy to prevent future epidemics similar to the 2019-nCoV outbreak

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生物安全与健康(英文) 2020年第1期2卷 6-8页

作者： Daszak Peter Olival j. kevin Li Hongying EcoHealth Alliance 460 West 34th Street New York NY 10001 USA

A novel bat-origin coronavirus emerged in Wuhan, China in December 2019 and continues to spread across China and the world. At the time of writing, a massive global response has been implemented to control the disease as it spreads from person to person. Yet the high-risk human-wildlife interactions and interfaces that led to the emergence of SARS-CoV and of 2019-nCoV continue to exist in emerging disease hotspots globally. To prevent the next epidemic and pandemic related to these interfaces, we call for research and investment in three areas: 1) surveillance among wildlife to identify the high-risk pathogens they carry; 2) surveillance among people who have contact with wildlife to identify early spillover events; and 3) improvement of market biosecurity regarding the wildlife trade. As the emergence of a novel virus anywhere can impact the furthest reaches of our connected world, international collaboration among scientists is essential to address these risks and prevent the next pandemic.

关键词： Novel coronavirus Disease emergence SurveillanceRisk reductionMarket biosecurity 2019-nCoV

Macular carotenoid supplementation improves disability glare performance and dynamics of photostress recovery

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Eye and Vision 2016年第1期3卷 231-238页

作者： j.mes M.Stringham kevin j.O’Brien Nicole T.Stringham Nutritional Neuroscience Laboratory Department of Physiology and PharmacologyUniversity of GeorgiaAthensGA 30602USA Vision Sciences Laboratory Department of PsychologyUniversity of GeorgiaAthensGA 30602USA Interdisciplinary Neuroscience Program Biomedical Health Sciences InstituteUniversity of GeorgiaAthensGA 30602USA

Background:The so-called macular carotenoids(MC)lutein(L),zeaxanthin(Z),and meso-zeaxanthin(MZ)comprise the diet-derived macular pigment(MP).The purpose of this study was to determine effects of MC supplementation on the optical density of MP(MPOD),repeated-exposure photostress recovery(PSR),and disability glare(DG)***:This was a double-blind,placebo-controlled ***-nine young(mean age=21.7),healthy volunteers participated in this *** supplemented their daily diet with either 10 mg L+2 mg total Z(1 mg Z+1 mg MZ;n=24),20 mg L+4 mg total Z(2 mg Z+2 mg MZ;n=25),or placebo(n=10)for 12 *** primary outcome was a composite measure of visual performance in glare,defined by change in DG and *** outcomes included MPOD and visual *** primary endpoint for outcomes was 12 *** was assessed with customized heterochromatic flicker *** times for an 8 cycle/degree,15%contrast Gabor patch target were determined after each of five successive exposures to intense LED *** threshold was defined as the intensity of a ring of lights through which subj.cts were able to maintain visibility of the aforementioned *** of all parameters were conducted at baseline,6 months,and 12 ***-measures ANOVA,and Pearson product-moment correlations were used to determine statistically significant correlations,and changes within and between ***:MPOD for subj.cts in both supplementation groups increased significantly versus placebo at both 6-and 12-month visits(pj.cts’DG thresholds were significantly related to chang

关键词： Lutein Zeaxanthin Mesozeaxanthin Visual performance Photostress recovery Disability glare Macular pigment Visual cycle