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Human umbilical cord derived mesenchymal stem cells in peripheral nerve regeneration

World Journal of stem Cells 2020年第4期12卷 288-302页

作者： Christine Bojanic Kendrick To Bridget Zhang christopher Mak Wasim s Khan Department of Plastic and Reconstructive surgery Cambridge University Hospitals NHS TrustCambridge CB20QQUnited Kingdom Division of Trauma and Orthopaedic surgery Addenbrooke's HospitalUniversity of CambridgeCambridge CB20QQUnited Kingdom school of Clinical Medicine University of CambridgeCambridge CB20QQUnited Kingdom

BACKGROUND Peripheral nerve injury can occur as a result of trauma or disease and carries significant morbidity including sensory and motor *** body has limited ability for nerve regeneration and functional *** untreated,nerve lesions can cause lifelong *** treatment options such as neurorrhaphy and neurolysis have high failure *** reconstruction with autograft carries donor site morbidity and often provide suboptimal *** stem cells(MsCs)are known to have promising regenerative potential and have gained attention as a treatment option for nerve *** is however,unclear whether it can be effectively used for nerve *** To evaluate the evidence for the use of human umbilical cord derived MsCs(UCMsCs)in peripheral nerve *** We carried out a systematic literature review in accordance with the PRIsMA protocol.A literature search was performed from conception to september 2019 using PubMed,EMBAsE and Web of *** results of eligible studies were appraised.A risk of bias analysis was carried out using Cochrane’s RoB 2.0 *** Fourteen studies were included in this review.A total of 279 subjects,including both human and animal were treated with *** studies obtained UCMsCs from a third-party source and the remainder were harvested by the *** of the 14 studies,thirteen conducted xenogenic transplantation into nerve injury *** studies reported significant improvement in nerve regeneration in the UCMsC treated groups compared with the various different controls and untreated *** The evidence summarised in this PRIsMA systematic review of in vivo studies supports the notion that human UCMsC transplantation is an effective treatment option for peripheral nerve injury.

关键词： Umbilical cord Mesenchymal stem cells Transplantation Peripheral nerve regeneration

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signal integration in the （m）TORC1 growth pathway

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Frontiers in Biology 2018年第4期13卷 237-262页

作者： Kailash Ramlaul christopher H. s. Aylett section of structural Biology Department of Medicine Imperial College London SW7 2AZ UK

BACKGROUND： The protein kinase Target Of Rapamycin （TOR） is a nexus for the regulation of eukaryotic cell growth. TOR assembles into one of two distinct signalling complexes, TOR complex 1 （TORC1） and TORC2 （mTORC1/2 in mammals）, with a set of largely non-overlapping protein partners. （m）TORC 1 activation occurs in response to a series of stimuli relevant to cell growth, including nutrient availability, growth factor signals and stress, and regulates much of the cell＇s biosynthetic activity, from proteins to lipids, and recycling through autophagy, mTORC1 regulation is of great therapeutic significance, since in humans many of these signalling complexes, alongside subunits of mTORC1 itself, are implicated in a wide variety of pathophysiologies, including multiple types of cancer, neurological disorders, neurodegenerative diseases and metabolic disorders including diabetes. METHODOLOGY： Recent years have seen numerous structures determined of （m）TOR, which have provided mechanistic insight into （m）TORC 1 activation in particular, however the integration of cellular signals occurs upstream of the kinase and remains incompletely understood. Here we have collected and analysed in detail as many as possible of the molecular and structural studies which have shed light on （m）TORC 1 repression, activation and signal integration. CONCLUsIONs： A molecular understanding of this signal integration pathway is required to understand how （m）TORC1 activation is reconciled with the many diverse and contradictory stimuli affecting cell growth. We discuss the current level of molecular understanding of the upstream components of the （m）TORC1 signalling pathway, recent progress on this key biochemical frontier, and the future studies necessary to establish a mechanistic understanding of this master-switch for eukaryotic cell growth.

关键词： mTORC 1 nutrient sensing GATOR complex TsC complex Rag GTPases Rheb

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Tessellations in GIs:Part I—putting it all together

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Geo-spatial Information science 2016年第1期19卷 9-25页

作者： christopher Gold Faculty of Computing Engineering and ScienceUniversity of South WalesWalesUK Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengduChina state Key Laboratory of Information Engineering in surveying Mapping and Remote Sensing(LIESMARS)Wuhan UniversityWuhanChina

This article attempts to describe the role of tessellated models of space within the discipline of geographic information systems(GIs)—a speciality coming largely out of geography and land surveying,where there was a strong need to represent information about the land’s surface within a computer system rather than on the original paper *** look at some of the basic operations in GIs,including dynamic and kinetic *** examine issues of topology and data structures and produce a tessellation model that may be widely applied both to traditional“object”and“field”data *** on this framework,it can be argued that tessellation models are fundamental to our understanding and processing of geographical space,and provide a coherent framework for understanding the“space”in which we *** first article examines static structures,and a subsequent article looks at“change”—what happens when things move.

关键词： GIs tessellation model static structure topology data structure object and field Voronoi diagram

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science of empirical design in mining ground control

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International Journal of Mining science and Technology 2016年第3期26卷 461-470页

作者： Mark christopher MsHA Pittsburgh Safety & Health Technology Center

Many problems in rock engineering are limited by our imperfect knowledge of the material properties and failure mechanics of rock masses. Mining problems are somewhat unique, however, in that plenty of real world experience is generally available and can be turned into valuable experimental *** pillar that is developed, or stope that is mined, represents a full-scale test of a rock mechanics design. By harvesting these data, and then using the appropriate statistical techniques to interpret them,mining engineers have developed powerful design techniques that are widely used around the *** empirical methods are readily accepted because they are simple, transparent, practical, and firmly tethered to reality. The author has been intimately associated with empirical design for his entire career, but his previous publications have described the application of individual techniques to specific problems. The focus of this paper is the process used to develop a successful empirical method. A sixstage process is described: identification of the problem, and of the end users of the final product; development of a conceptual rock mechanics model, and identification of the key parameters in that model;identification of measures for each of the key parameters, and the development of new measures(such as rating scales) where necessary; data sources and data collection; statistical analysis; and packaging of the final product. Each of these stages has its own potential rewards and pitfalls, which will be illustrated by incidents from the author's own experience. The ultimate goal of this paper is to provide a new and deeper appreciation for empirical techniques, as well as some guidelines and opportunities for future developers.

关键词： Design Pillar stope Empirical statistics Modeling

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Legacy earthen berms influence vegetation and hydrologic complexity in the Altar Valley,Arizona

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International soil and Water Conservation Research 2023年第4期11卷 755-763页

作者： Mary H.nichols sara E.Duke Chandra Holifield Collins Lauren Thompson southwest Watershed Research Center USDA-ARS2000 E.Allen Rd.TucsonAZ85719USA southern Plains Area Research Center USDA-ARSSPARCCollege StationTX77845USA University of Arizona College of Science GraduateTucsonAZ85719USA

Across the American southwest water development has played a critical role in managing *** berms have been constructed throughout Us rangelands to manage runoff and reduce *** berms altered runoff patterns to increase soil moisture with positive local vegetative ***,altered runoff patterns can be considered a disturbance that affects broader scale vegetation *** hypothesized that the hydrologic impacts of earthen berms in semiarid rangelands will be reflected in contrasting upslope and downslope vegetation patterns.A supervised classification of grass,shrubs,and bare soil was performed using orthographic imagery taken in June 2016 to quantify the effects of 181 earthen berms in the uplands and floodplain of the Altar Valley in southern Arizona,*** berms blocked runoff,creating downslope runoff"shadows"within which the precipitation is the dominant water *** documented more bare soil downslope of intact berms in comparison with *** and shrub cover affected by berms were related to soil *** and shrub cover were not different above and below intact berms on fine textured soils,but on sites with coarser textured soil,grass cover was lower downslope of *** breaches occurred on coarser textured soils,the up and downslope differences in grass cover *** study points to the role of conservation structures in adding additional complexity to already heterogeneous landscapes by creating patchwork assemblages of vegetation and bare soil proximal to earthen runoff and erosion control berms.

关键词： Legacy conservation structure Earthen bank Earthen berm Land degradation Rangeland

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On the use of residual dipolar couplings in multi-state structure calculation of two-domain proteins

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Magnetic Resonance Letters 2022年第2期2卷 61-68,I0002页

作者： Alexandra Born Morkos A.Henen Parker J.nichols Beat Vogeli University of Colorado Anschutz Medical Campus Department of Biochemistry and Molecular Genetics12801 East 17th AvenueAuroraCO80045USA Faculty of Pharmacy Mansoura UniversityMansoura35516Egypt

Residual dipolar couplings(RDCs)are powerful nuclear magnetic resonance(NMR)probes for the structure calculation of ***,an alignment tensor that defines the orientation of the entire molecule relative to the magnetic field is determined either before refinement of individual bond vectors or simultaneously with this *** single-domain proteins this approach works well since all bond vectors can be described within the same coordinate frame,which is given by the alignment ***,novel approaches are sought after for systems where no universal alignment tensor can be ***,we present an approach that can be applied to two-domain proteins that enables the calculation of multiple states within each domain as well as with respect to the relative positions of the two domains.

关键词： RDC Residual dipolar coupling Two-domain protein Multi-state structure

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Unanticipated multiple seam stresses from pillar systems behaving as pseudo gob–case histories

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International Journal of Mining science and Technology 2017年第1期27卷 131-137页

作者： Gauna Michael Mark christopher Pittsburgh safety and Health Technology Center Mine Safety and Health Administration(MSHA)PittsburghPA 15236USA

Underground coal mining in the U.s. is conducted in numerous regions where previous workings exist above and/or below an actively mined seam. Miners know that overlying or underlying fully extracted coal areas, also known as gob regions, can result in abutment stresses that affect the active mining. If there was no full extraction, and the past mining consists entirely of intact pillars, the stresses on the active seam are usually minimal. However, experience has shown that in some situations there has been sufficient yielding in overlying or underlying pillar systems to cause stress transfer to the adjoining larger pillars or barriers, which in turn, transfer significant stresses onto the workings of the active seam. In other words, the overlying or underlying pillar system behaves as a ‘‘pseudo gob." The presence of a pseudo gob is often unexpected, and the consequences can be severe. This paper presents several case histories, summarized briefly below, that illustrate pseudo gob phenomenon:(1) pillar rib degradation at a West Virginia mine at 335 m depth that contributed to a rib roll fatality,(2) pillar rib deterioration at a Western Kentucky mine at 175 m depth that required pillar size adjustment and installation of supplemental bolting,(3) roof deterioration at an eastern Kentucky mine at 400 m depth that stopped mine advance and required redirecting the section development,(4) coal burst on development at an eastern Kentucky mine at 520 m depth that had no nearby pillar recovery, and(5) coal burst on development at a West Virginia mine at the relatively shallow depth of 335 m that also had no nearby pillar recovery. The paper provides guidance so that when an operation encounters a potential pseudo gob stress interaction the hazard can be mitigated based on an understanding of the mechanism encountered.

关键词： Underground mining Coal Multiple seam Gob Ground control

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Biological and cultural diversity in the context of botanic garden conservation strategies

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Plant Diversity 2017年第6期39卷 396-401页

作者： christopher P.Dunn Cornell Botanic Gardens 124 Comstock Knoll Drive Cornell University

Impacts of global climate change, habitat loss, and other environmental changes on the world's biota and peoples continue to increase, especially on islands and in high elevation areas. Just as floristic diversity is affected by environmental change, so too are cultural and linguistic diversity. Of the approximately 7000 extant languages in the world, fully 50% are considered to be at risk of extinction, which is considerably higher than most estimates of extinction risks to plants and animals. To maintain the integrity of plant life, it is not enough for botanic gardens to consider solely the effects of environmental change on plants within the context of major conservation strategies such as the Global strategy for Plant Conservation and the Convention on Biological Diversity. Rather, botanic gardens should actively engage in understanding and communicating the broader impacts of environmental change to biological and cultural diversity.

关键词： Biocultural diversity Botanic gardens Linguistic diversity Plant diversity

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Atomic layer deposition: Catalytic preparation and modification technique for the next generation

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Chinese Journal of Catalysis 2019年第9期40卷 1311-1323页

作者： Hongbo Zhang christopher L. Marshall school of Materials science and Engineering & National Institute for Advanced Materials Nankai UniversityTianjin 300350China Chemical sciences and Engineering Division Argonne National Laboratory9700 South Cass AvenueLemontIL60439USA

Atomic layer deposition(ALD)attracts great attention nowadays due to its ability for designing and modifying catalytic systems at the molecular *** are several reported review papers published recently discussing this technique in ***,the mechanism on how the deposited materials improve the catalyst stability and tune the reaction selectivity is still ***,catalytic systems created via ALD on stepwise preparation and/or modification under self-limiting reaction conditions are *** effects of deposited materials in terms of electronic/geometry modification over the catalytic nanoparticles(NPs)are *** effects explain the mechanism of the catalytic stability improvement and the selectivity *** unique properties of ALD for designing new catalytic systems are further investigated for building up photocatalytic reaction nanobowls,tandem catalyst and bi-active-component metallic catalytic systems.

关键词： Atomic layer deposition Catalyst modification Catalyst preparation Redox properties Terrace site step site

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Development process for a higher capacity Propsetter~ system

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International Journal of Mining science and Technology 2018年第1期28卷 121-126页

作者： christopher J.Brown Product Development-strata Worldwide LLC

As longwall tailgate support technologies continue to be developed and improved, strata worldwide has worked to design and manufacture a revised Propsetter to provide additional support capacity and enable applications at greater mine *** support is targeted for tailgate applications, however, it can also be utilized for roof support in various types of mining *** paper describes the design changes for enhancing the support capacity of the Propsetter to more closely align its performance with other support technologies currently being employed in longwall *** changes to each design aspect of the Propsetter was key to successfully improving the roof support's load capacity while maintaining controlled *** the load capacity would allow a mine to improve support efficiency with a smaller, less intrusive support compared to support alternatives and reduce the cost per foot of supported *** target support capacity was 711–890 k N at 50 mm of deformation to more closely match the performance of competing tailgate supports such as the 610 mm-diameter CAN~.To achieve this goal, changes were made to all design aspects of the Propsetter: diameter, wedge cut depth and angle, pod size, and confinement *** results from the NIOsH Mine Roof simulator verified that these design changes were successful in increasing the capacity of the Propsetter to the 711–890 k N range at fifty mms of deformation.

关键词： Propsetter Can Longwall mining Tailgate roof support Controlled deformation

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