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Inflammatory priming of mesenchymal stem cells:Focus on growth factors enhancement

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BIOCELL 2022年第9期46卷 2049-2052页

作者： aleksandra GORNOSTAEVA ELENA ANDREEVA LUDMILA BURAVKOVA Cell Physiology Laboratory Institute of Biomedical Problems of Russian Academy of SciencesMoscow123007Russia

Multipotent mesenchymal stromal cells(MSCs)are actively involved in reparation and inflammation processes,providing damaged tissue reparation and suppressing immune cell responses in *** effects are mostly due to the production of a wide range of paracrine factors,including growth factors and immunomodulatory *** induce immunosuppressive activity,MSCs are primed by inflammatory cytokines,which results in an increased production of immunomodulatory ***,stimulation of reparative properties is also *** viewpoint manuscript highlights the possibilities of inflammatory priming to increase the production of growth factors by MSCs.

关键词： Multipotent mesenchymal stromal cells Priming Growth factors

Bracken-induced increase in soil P availability, along with its high P acquisition efficiency, enables it to invade P-deficient meadows

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Journal of Plant Ecology 2022年第4期15卷 783-794页

作者： Antun Jelinčić Nina Šajna Željka Zgorelec aleksandra Perčin Ćire Truhelke 1510000 ZagrebCroatia University of Maribor Faculty of Natural Sciences and MathematicsDepartment of BiologyMariborSlovenia University of Zagreb Faculty of AgricultureDepartment of General AgronomyZagrebCroatia

Changes in soil chemistry after invasion by bracken(Pteridium aquilinum)have been studied in heathlands,but comparable studies in meadows are *** investigated if bracken invasion into P-deficient meadows alters the soil nutrient-resource pool,as well as the mechanisms behind it linked to soil processes and bracken ***,we investigated how community composition responds to differences in soil chemistry before and after the *** and plant material sampling,along with vegetation survey,were performed during bracken peak *** analyses included analysis of variance and canonical correspondence analysis(CCA).Bracken invasion increased soil P availability,soil organic C concentration,as well as C:N,C:S and N:S ratios,while decreasing Fe and Co *** pinnae were rich in P,and its rhizomes were rich in K,whereas N:P of pinnae and rhizomes was *** showed contrasting abundance patterns of frequent meadow species related to P and K *** lanatus exhibited competitive advantage under extremely low P *** in P availability under bracken may have occurred through promoting the leaching of Fe and *** increasing P availability for its growth and increasing N limitation for other species,bracken can gain a competitive advantage from the soil resource-niche *** ability to increase soil P availability,along with the physiological mechanisms behind its high P acquisition efficiency,seem to differentiate bracken from other species of competitive ecological strategy,which are mainly confined to nutrient-rich *** enabled bracken to invade P-deficient meadows.

关键词： Pteridium aquilinum vegetation succession biogeochemical processes plant–soil feedbacks Holcus lanatus phosphorus limitation plant invasion

Taming desynchronized bursting with delays in the Macaque cortical network

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Chinese Physics B 2011年第4期20卷 117-122页

作者：王青云 Murks aleksandra Perc Matjaz 陆启韶 Department of Dynamics and Control Beihang University Department of Physics Faculty of Natural Sciences and MathematicsUniversity of Maribor

Inhibitory coupled bursting Hindmarsh-Rose neurons are considered as constitutive units of the Macaque corti- cal network. In the absence of information transmission delay the bursting activity is desynchronized, giving rise to spatiotemporally disordered dynamics. This paper shows that the introduction of finite delays can lead to the synchro- nization of bursting and thus to the emergence of coherent propagating fronts of excitation in the space-time domain. Moreover, it shows that the type of synchronous bursting is uniquely determined by the delay length, with the transi- tions from one type to the other occurring in a step-like manner depending on the delay. Interestingly, as the delay is tuned close to the transition points, the synchronization deteriorates, which implies the coexistence of different bursting attractors. These phenomena can be observed by different but fixed coupling strengths, thus indicating a new role for information transmission delays in realistic neuronal networks.

关键词： synchronization bursting information transmission delay Macaque cortical network inhibitory coupling

Stable optical vortices in nonlinear multicore fibers

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Light(Science & Applications) 2015年第1期4卷 245-250页

作者： Ljupco Hadzievski aleksandra Maluckov Alexander MRubenchik Sergei Turitsyn Vinca Institute of Nuclear Sciences University of BelgradeP.O.Box 52211001 BelgradeSerbia Lawrence Livermore National Laboratory LivermoreCalifornia 94550USA Aston Institute of Photonic Technologies Aston UniversityB47ET BirminghamUK Laboratory of Nonlinear Photonics Novosibirsk State UniversityNovosibirsk630090Russia

The multicore fiber(MCF)is a physical system of high practical *** addition to standard exploitation,MCFs may support discrete vortices that carry orbital angular momentum suitable for spatial-division multiplexing in high-capacity fiber-optic communication *** discrete vortices may also be attractive for high-power laser *** present the conditions of existence,stability,and coherent propagation of such optical vortices for two practical MCF *** optimization,we found stable discrete vortices that were capable of transferring high coherent power through the MCF.

关键词： coherent energy propagation multicore fibers nonlinear vortices

Novel synthesis method combining a foaming agent with freeze-drying to obtain hybrid highly macroporous bone scaffolds

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Journal of Materials Science & Technology 2020年第8期36卷 52-63页

作者： Paulina Kazimierczak aleksandra Benko Krzysztof Palka Cristina Canal Dorota Kolodynska Agata Przekora Department of Biochemistry and Biotechnology Medical University of LublinChodzki 120-093LublinPoland AGH University of Science and Technology Faculty of Materials Science and CeramicsA.Mickiewicza 30 Ave.30-059KrakowPoland Department of Materials Engineering Lublin University of TechnologyNadbystrzycka 3620-618LublinPoland Biomaterials Biomechanics and Tissue Engineering GroupDepartment of Materials Science and MetallurgyUniversitat Politècnica de CatalunyaBarcelona08019Spain Research Centre in Multiscale Science and Engineering Universitat Politècnica de CatalunyaBarcelona08019Spain Department of Inorganic Chemistry Maria Curie-Sklodowska UniversityMaria Curie Sklodowska Sq.220-031LublinPoland

Three-dimensional macroporous scaffolds are commonly used in bone tissue engineering applications since they provide sufficient space for cell migration and proliferation, facilitating bone ingrowth and implant vascularisation. The aim of this work was to combine two simple methods, freeze-drying and gas-foaming, in order to fabricate highly macroporous bone scaffolds made of chitosan/agarose matrix reinforced with nanohydroxyapatite. The secondary goal of this research was to comprehensively assess biomedical potential of developed biomaterials. In this work, it was demonstrated that simultaneous application of freeze-drying and gas-foaming technique allows to obtain hybrid(as proven by ATR-FTIR)macroporous bone scaffolds(pore diameter > 50 um) characterized by high open(70%) and interconnected porosity. Novel scaffolds were non-toxic, favoured osteoblasts adhesion and growth and induced apatite formation on their surfaces, indicating their high bioactivity that is essential for good implant osseointegration. Biomaterials were also prone to enzymatic degradation, degradation in acidified microenvironment(e.g. osteoclast-mediated), and slow degradation under physiological p H of ***, the scaffolds revealed microstructure(70% open porosity, SSA approx. 30 m2/g, high share of macropores with diameter in the range 100-410 um) and compressive strength(1–1.4 MPa) comparable to cancellous bone, indicating that they are promising implants for cancellous bone regeneration.

关键词： Agarose Chitosan Nanohydroxyapatite Biomaterial porosity Biodegradation Cryogel

Assessing suspended sediment fluxes with acoustic Doppler current profilers:case study from large rivers in Russia

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Big Earth Data 2022年第4期6卷 504-526页

作者： Sergey Chalov Vsevolod Moreido Victor Ivanov aleksandra Chalova Faculty of Geography Lomonosov Moscow State UniversityMoscowRussia Institute of Physics Kazan Federal UniversityKazanRussia Flood Hydrology Lab Water Problems Institute of Russian Academy of SciencesMoscowRussia

Surrogate measures are becoming increasingly used to measure suspended sediment flux,but only few particular computer techniques of data processing are recently *** study demonstrates capabilities of acoustic Doppler current profilers(ADCPs)to infer information regarding suspended-sand concentrations in river systems and calculate suspended sediment flux via big data analytics which includes process of analyzing and data mining of measurements based on ADCP signal backscatter intensity *** present here specific codes done by R language using RStudio software with open-source tidyverse and plotly packages aimed to generate tables containing data of suspended load for cells,verticals and whole cross-section based on backscattering values from 600 kH Teledyne RDInstruments RioGrande WorkHorse ADCP unit,as well perform estimates of morphometric,suspended sediment concentration(SSC)and velocity characteristics of the *** developed tools enabled to process large data array consisting of over 56,526,480 geo-referenced values of river depth,streamflow velocity,and backscatter intensity for each river cross-section measured at six case study sites in Russia.

关键词： Big data ADCP backscatter intensity sediment transport

Research on China’s Engagement in Central and Eastern Europe under Belt and Road *** Study of Poland.

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Research on China’s Engagement in Central and Eastern Europ...

作者： aleksandra Januszewska 山东大学

学位级别：硕士

This research focuses on the issue of Chinese involvement in Central and Eastern Europe as part of the Belt and Road *** Belt and Road Initiative refers to the Silk Road Economic Belt and 21st Century Maritime Silk *** is visionary,long-term initiative raised by Chinese Government to foster closer economic,political,cultural and social links across Asia to the Middle East,Europe and *** in the Central and Eastern Europe region is manifested through the activities and use of the 17+1 *** platform is an integral part of *** its first part,the paper justifies the importance of the subject *** main arguments are the need to strengthen cooperation between regions for sustainable development,strengthening the position of the CEE countries on the international arena,and naturally building a counterweight to the influence of such powers as the United States or *** paper discusses the impact of Chinese policy on the CEE countries and points out the most important cooperation challenges,among others in the 17+1 *** part discusses political,economic and social and cultural influence of Chinese policies upon CEE *** following chapter of the paper indicates the important role played by local governments in shaping relations between China and *** study of Poland is discussed in *** connection network,postulated as part of the Belt and Road Initiative,takes Poland into account as a key country when creating the shortest land connection between China and Western *** that is why the last chapter is a case study Poland’s position in the Belt and Road Initiative and the challenges it *** conclusions indicate the steps to be taken to improve cooperation and to make China’s involvement in the CEE region more effective.

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Instrumented and Vickers Indentation for the Characterization of Stiffness,Hardness and Toughness of Zirconia Toughened Al_2O_3 and SiC Armor

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Journal of Materials Science & Technology 2015年第8期31卷 773-783页

作者： aleksandra Nastic Ali Merati Mariusz Bielawski Manon Bolduc Olaniyi Fakolujo Michel Nganbe Department of Mechanical Engineering University of Ottawa National Research Council Canada Defence R&D Canada(DRDC Valcartier)

Instrumented and Vickers indentation testing and microstructure analysis were used to investigate zirconia toughened alumina （ZTA） and silicon carbide （SIC）. Several equations were studied to relate the Vickers indentation hardness, Young＇s modulus and crack behavior to the fracture toughness. The frac- ture in SiC is unstable and occurs primarily by cleavage leading to a relatively low toughness of 3 MPa m1/2, which may be inappropriate for multi-hit capability. ZTA absorbs energy by plastic deformation, pore collapse, crack deviation and crack bridging and exhibits time dependent creep. With a relatively high toughness around 6.6 MPa m1/2, ZTA is promising for multi-hit capability. The higher accuracy of median equations in calculating the indentation fracture toughness and the relatively high c/a ratios above 2.5 suggest median type cracking for both SiC and ZTA. The Young＇s modulus of both ceramics was most accurately measured at lower indentation loads of about 0.5 kgf, while more accurate hardness and fracture toughness values were obtained at intermediate and at higher indentation loads beyond 5 kgf, respectively. A strong indentation size effect （ISE） was observed in both materials. The load independent hardness of SiC is 2563 HV, putting it far above the standard armor hardness requirement of 1500 HV that is barely met by ZTA.

关键词： Zirconia toughened alumina Silicon carbide Armor Vickers indentation fracture toughness Elastic modulus Vickers hardness

Giant pseudoaneurysm of the splenic artery within walled of pancreatic necrosis on the grounds of chronic pancreatitis

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Hepatobiliary & Pancreatic Diseases International 2021年第1期20卷 87-89页

作者： Milica Mitrovic Jovanovic Dusan Saponjski aleksandra Djuric Stefanovic aleksandra Jankovic Stefan Milosevic Katarina Stosic Djordje Knezevic Jelena Kovac Department of Abdominal Radiology Center for Radiology and MRIClinical Center of SerbiaBelgradeSerbia Faculty of Medicine University of BelgradeBelgradeSerbia Clinic for Digestive Surgery–First Surgical Clinic Clinical Center of SerbiaBelgradeSerbia

Chronic pancreatitis is a long-standing inflammation of the pancreas,characterized by progressive inflammatory and fibrotic changes,resulting in permanent structural damage of pancreatic parenchyma[1].Pancreatitis(chronic or acute)is the primary risk factor for pseudo-splenic artery aneurysms,along with pancreatic pseudocysts and *** the disease progresses,patients with chronic pancreatitis may develop complications due to exocrine and endocrine pancreatic functional loss,such as fat malabsorption with steatorrhea,glucose intolerance,and ultimately diabetes mellitus[1,2].Furthermore,severe pancreatic inflammation can cause weakening of vessel walls,with subsequent formation of arterial *** artery is the most commonly affected visceral artery[2,3].Liver cirrhosis,portal hypertension,liver transplantation,atherosclerosis,hypertension,pregnancy and multiparity are main risk factors for true splenic artery aneurysms[2].Rupture and intraperitoneal bleeding is the cause of death in 30%−50%of ***,prompt diagnosis and appropriate treatment are of great clinical importance[4,5].Herein,we present a case of a giant splenic artery pseudoaneurysm within a walled of necrosis involving pancreatic parenchyma,as a complication of long standing chronic pancreatitis.

关键词： pancreatitis aneurysm inflammation