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Current progress in use of adipose derived stem cells in peripheral nerve regeneration

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World Journal of Stem Cells 2015年第1期7卷 51-64页

作者： Shomari DL Zack-Williams peter E Butler Deepak m Kalaskar Centre for Nanotechnology and Regenerative medicine Division of Surgery and Interventional Science University College London WC1E 6BT London United Kingdom Department of Plastic and Reconstructive Surgery Royal Free Hampstead NHS Trust Hospital NW3 2QG London United Kingdom

Unlike central nervous system neurons; those in the peripheral nervous system have the potential for full regeneration after injury. Following injury, recovery is controlled by schwann cells which replicate and modulate the subsequent immune response. The level of nerve recovery is strongly linked to the severity of the initial injury despite the significant advancements in imaging and surgical techniques. multiple experimental model shave been used with varying successes to augment the natural regenerative processes which occur following nerve injury. Stem cell therapy in peripheral nerve injury may be an important future intervention to improve the best attainable clinical results. In particular adipose derived stem cells(ADSCs) are multipotent mesenchymal stem cells similar to bone marrow derived stem cells, which are thought to have neurotrophic properties and the ability to differentiate into multiple lineages. They are ubiquitous within adipose tissue; they can form many structures resembling the mature adult peripheral nervous system. Following early in vitro work; multiple small and large animal in vivo models have been used in conjunction with conduits, autografts and allografts to successfully bridge the peripheral nerve gap. Some of the ADSC related neuroprotective and regenerative properties have been elucidated however much work remains before a model can be used successfully in human peripheral nerve injury(PNI). This review aims to provide a detailed overview of progress made in the use of ADSC in PNI, with discussion on the role of a tissue engineered approach for PNI repair.

关键词： Peripheral nerve injury Adipose derivedstem cells Cell based therapies Stem cells

Advances in surgical management for locally recurrent rectal cancer: How far have we come?

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World Journal of Gastroenterology 2017年第23期23卷 4170-4180页

作者： Daniel Jin-Keat Lee peter m Sagar Gaitri Sadadcharam Kok-Yang Tan Department of Surgery Khoo Teck Puat Hospital John Goligher Colorectal Surgery Unit St James’s University Hospital

Locally recurrent rectal cancer(LRRC) is a complex disease with far-reaching implications for the patient. Until recently, research was limited regarding surgical techniques that can increase the ability to perform an en bloc resection with negative margins. This has changed in recent years and therefore outcomes for these patients have improved. Novel radical techniques and adjuncts allow for more radical resections thereby improving the chance of negative resection margins and outcomes. In the past contraindications to surgery included anterior involvement of the pubic bone, sacral invasions above the level of S2/S3 and lateral pelvic wall involvement. However, current data suggests that previously unresectable cases may now be feasible with novel techniques, surgical approaches and reconstructive surgery. The publications to date have only reported small patient pools with the research conducted by highly specialised units. moreover, the short and long-term oncological outcomes are currently under review. Therefore although surgical options for LRRC have expanded significantly, one should balance the treatment choices available against the morbidity associated with the procedure and select the right patient for it.

关键词： Recurrent rectal cancer Sacrectomy Pelvic exenteration Pelvic sidewall Radical resection

Intra-and Intermolecular Rovibrational States of HCl-H_(2)O and DCl-H_(2)O Dimers from Full-Dimensional and Fully Coupled Quantum Calculations

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Chinese Journal of Chemical Physics 2021年第6期34卷 728-740,I0002页

作者： peter m.Felkera Zlatko Bacic Department of Chemistry and Biochemistry University of CaliforniaLos AngelesCA 90095-1569USA Department of Chemistry New York UniversityNew York 10003USA NYU-ECNU Center for Computational Chemistry at NYU Shanghai Shanghai 200062China

We report full-dimensional and fully coupled quantum bound-state calculations of the J=1 intra-and intermolecular rovibrational states of two isotopologues of the hydrogen chloride-water dimer,HClH_(2)O(HH)and DCl-H_(2)O(DH).The present study complements our recent theoretical investigations of the J=0 nine-dimensional(9D)vibrational level structure of these and two other H/D isotopologues of this noncovalently bound molecular complex,and employs the same accurate 9D permutation invariant polynomial-neural network potential energy *** calculations yield all intramolecular vibrational fundamentals of the HH and DH dimers and the low-energy intermolecular rovibrational states in these intramolecular vibrational *** results are compared with those of the 9D J=0 calculations of the same *** energy differences between the K=1 and K=0 eigenstates exhibit pronounced variations with the intermolecular rovibrational states,for which a qualitative explanation is provided.

关键词： Weakly bound dimers Rovibrational states Quantum calculations

On the Use of Adjoint-Based Sensitivity Estimates to Control Local mesh Refinement

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Communications in Computational Physics 2010年第3期7卷 631-638页

作者： Joseph D.Frazier peter K.Jimack Robert m.Kirby School of Computing University of UtahSalt Lake CityUTUSA School of Computing University of LeedsLeedsLS29JTUK

The goal of efficient and robust error control, through local mesh adaptationin the computational solution of partial differential equations, is predicated on theability to identify in an a posteriori way those localized regions whose refinement willlead to the most significant reductions in the error. The development of a posteriori errorestimation schemes and of a refinement infrastructure both facilitate this goal, howeverthey are incomplete in the sense that they do not provide an answer as to where themaximal impact of refinement may be gained or what type of refinement — elementalpartitioning (h-refinement) or polynomial enrichment (p-refinement) — will best leadto that gain. In essence, one also requires knowledge of the sensitivity of the error toboth the location and the type of refinement. In this communication we propose theuse of adjoint-based sensitivity analysis to discriminate both where and how to *** present both an adjoint-based and an algebraic perspective on defining and usingsensitivities, and then demonstrate through several one-dimensional model problemexperiments the feasibility and benefits of our approach.

关键词： Adaptivity error estimation hp-finite elements sensitivity discrete adjoint

HOTSPOTS OF NUTRIENT LOSSES TO AIR AND WATER:AN INTEGRATED mODELING APPROACH FOR EUROPEAN RIVER BASINS

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Frontiers of Agricultural Science and Engineering 2023年第4期10卷 579-592页

作者： Aslihan URAL-JANSSEN Carolien KROEZE Jan peter LESSCHEN Erik mEERS peter J.T.m.VANPUIJENBROEK maryna STROKAL Water Systems and Global Change Group Wageningen University&ResearchPO Box 476700AA Wageningenthe Netherlands Environmental Systems Analysis Group Wageningen University&ResearchPO Box 476700AA Wageningenthe Netherlands Wageningen Environmental Research PO Box 476700AA Wageningenthe Netherlands. Laboratory of Bioresource Recovery(RE-soURCE LAB) Ghent UniversityCoupure Links 6539000 GhentBelgium. PBL The Netherlands Environmental Assessment AgencyPO Box 303142500GH The Haguethe Netherlands.

Nutrient pollution of air and water is a persistent problem in ***,the pollution sources are often analyzed separately,preventingthe formulation of integrative *** study aimed to quantify the contribution of agriculture to air,river and coastal water pollution by nutrients.A new mARINA-Nutrients model was developed for Europe to calculate inputs of nitrogen(N)and phosphorus(P)to land and rivers,N emissions to air,and nutrient export to seas by river *** current practice,inputs of N and P to land were 34.4 and 1.8 ***^(-1),***,only 12%of N and 3%of P reached the *** was responsible for 55%of N and sewage for 67%of P in *** N emissions to air from agriculture were calculated at 4.0 ***^(-1).Almost twofifths of N emissions to air were from animal housing and *** a third of the basin area was considered as pollution hotspots and generated over half of N emissions to air and nutrient pollution in *** 25%of river export of N ended up in the Atlantic Ocean and of P in the mediterranean *** results could support environmental policies to reduce both air and water pollution simultaneously,and avoid pollution swapping.

关键词： agriculture air-water modeling European rivers nutrient pollution sewage systems source attribution

The tropical-subtropical evergreen forest transition in East Asia:An exploration

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Plant Diversity 2020年第4期42卷 255-280页

作者： peter Ashton Hua Zhu Arnold Arboretum Harvard UniversityRoyal Botanic GardensKewUK Center for Integrative Biology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesYunnanPR China

The transition from tropical to subtropical(warm temperate)evergreen forests is more clearly apparent in East Asia,fromNepal to the western Pacific coast,than elsewhere in the *** review the nature of this transition and hypothesize the physical,ultimately climatic,factors thatmay maintain it,with a special focus on how the increasing instability and warming of climates will affect these forests.A primary climatic mediator of the transition is proposed,thereby offering a testable hypothesis for the climateeforest transition *** is known of this transition is summarized in context of the primary climatic mediators of elevational zonation of forest formations in equatorial Asia to the tree line,in the Himalaya at the India-Indo-Burma northern tropical margin,and as both elevational and latitudinal zonation in southern *** secondary edaphic and other physical changes are described for the Himalaya,and hypothesized for southern *** forest ecotones are seen to be primarily defined by tree floristic change,on which account changes in structure and physiognomy are *** montane tropical-subtropical transition in the Himalaya is narrowand observed to correlate with an as yet ill-defined frost line.A distinct tropical-subtropical transition forest is recognized in the southwest *** is a total change in canopy species at the Himalayan ecotone,but subcanopy tropical species persist along an elevational decline of c.400 *** latitudinal transition in South China is analogous,but here the tropical subcanopy component extends north over ten degrees latitude,albeit in *** tropical-subtropical transition is uniquely clear in East Asia because here alone a tropical wet summer-dry winter monsoon extends to 35north latitude,encompassing the subtropical evergreen forest,whereas subtropical evergreen forests elsewhere exist under drier temperate summer climate regimes.

关键词： Tropical Subtropical Forest transition Ecotone East Asia

Opportunities to Use DNA methylation to Distil Functional Elements in Large Crop Genomes

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molecular Plant 2019年第3期12卷 282-284页

作者： peter A.Crisp Jaclyn m.Noshay Sarah N.Anderson Nathan m.Springer Department of Plant and microbial Biology University of MinnesotaSaint PaulMN 5510&USA

DNA methylation is a chromatin modification that is often associated with the exciti ng and sometimes unpredictable patter ns of inheritanee that can unfold with epigenetic phenomena. The stability and heritability of DNA methylati on patter ns perhaps allow us to utilize DNA methylation profiles to distil the suite of potentially functional elements in large crop genomes. Here, we discuss the potential and possible ways to use the absence of DNA methylation to identify potential regulatory regions within intergenic sequences and the presence of DNA methylation to identify pseudogenes.

关键词： DNA methylation Large Crop Genomes

On variations of m, n-simply presented abelian p-groups

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Science China mathematics 2014年第9期57卷 1771-1784页

作者： DANCHEV peter Department of mathematics University of Plovdiv

We define a few new classes of p-primary abelian groups,and study their crucial properties,one of which is the so-called Nunke’s-esque *** are also closely related to n-simply presented groups from Keef and Danchev(2... 详细信息

关键词： m n-simply presented groups m n-totally projective groups potentially m n-simply presented groups completely m n-simply presented groups absolutely m n-simply presented groups

Characterization of the High-Strength mg–3Nd–0.5Zn Alloy Prepared by Thermomechanical Processing

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Acta metallurgica Sinica(English Letters) 2019年第3期32卷 321-331页

作者： Ji■í Kub■sek Drahomír Dvorsk■ Jozef Vesel■ peter min■rik m■ria Zemkov■ Dalibor Vojtěch Department of metals and Corrosion Engineering Faculty of Chemical Technology University of Chemistry and Technology Prague Department of Physics of materials Charles University

magnesium alloys based on Nd and Zn are promising materials for both aviation industry and medical *** mechanical properties of these materials can be achieved by thermomechanical processing such as extrusion or rolling and by aging treatment, which can significantly strengthen the alloy. The question remains especially about the connection of texture strength created in the alloys based on the specific conditions of preparation. This work focuses on the mg–3 Nd–0.5 Zn magnesium alloy prepared by hot extrusion of the as-cast state at two different temperatures combined with heat pre-treatment. Extrusion ratio of 16 and rate of 0.2 mm/s at 350 and 400 °C were selected for material preparation. The structures of prepared materials were studied by scanning electron microscopy and transmission electron microscopy. The effect of microstructure on mechanical properties was evaluated. Obtained results revealed the strong effect of thermal pre-treatment on final microstructure and mechanical properties of extruded materials. The Hall–Petch relation between grain size and tensile yield strength has been suggested in this paper based on the literature review and presented data. The observed behavior strongly supports the fact that the Hall–Petch of extruded mg–3Nd–0.5 Zn alloys with different texture intensities cannot be clearly estimated and predicted. In addition, Hall–Petch relations presented in literature can be sufficiently obtained only for fraction of the mg–3Nd–0.5 Zn alloys.

关键词： mg–Nd–Zn alloys Extrusion Thermal treatment microstructure mechanical properties