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Histological assessment in peripheral nerve tissue engineering

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Neural Regeneration Research 2014年第18期9卷 1657-1660页

作者： v.ctor Carriel Ingrid Garzón Miguel Alaminos Maria Cornelissen Department of Histology (Tissue Engineering Group) Faculty of MedicineUniversity of Granadaand Instituto de Investigación Biosanitariaibs Department of Basic Medical Sciences (Histology and Tissue Engineering Group) Faculty of MedicineGhent University

The histological analysis of peripheral nerve regeneration is one of the most used methods to demonstrate the success of the regeneration through nerve conduits. Nowadays, it is possible to evaluate different parameters of nerve regeneration by using histological, histochemical, immunohistochemical and ultrastructural techniques. The histochemical methods are very sensible and are useful tools to evaluate the extracellular matrix remodeling and the myelin sheath, but they are poorly specific. In contrast, the immunohistochemical methods are highly specific and are frequently used for the identification of the regenerated axons, Sehwann cells and proteins associated to nerve regeneration or neural linage. The ultrastructural techniques offer the possibility to perform a high resolution morphological and quantitative analysis of the nerve regeneration. However, the use of a single histological method may not be enough to assess the degree of regeneration, and the combination of different histological techniques could be necessary.

关键词： peripheral nerve regeneration histology, histochemistry immunohistochemistry quantitative histology

High-aspect-ratio nanoimprint process chains

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Microsystems & Nanoengineering 2017年第1期3卷 221-232页

作者： v.ctor J.Cadarso Nachiappan Chidambaram Loïc Jacot-Descombes Helmut Schift Laboratory for Micro-and Nanotechnology Research Division Synchrotron Radiation and NanotechnologyPaul Scherrer InstitutVilligen 5232Switzerland Micro Resist Technology GmbH Köpenicker Straße 325Berlin 12555Germany

Different methods capable of developing complex structures and building elements with high-aspect-ratio nanostructures combined with microstructures,which are of interest in nanophotonics,are *** originals for subsequent replication steps,two families of masters were developed:(i)3.2μm deep,180 nm wide trenches were fabricated by silicon cryo-etching and(ii)9.8μm high,350 nm wide ridges were fabricated using 2-photon polymerization direct laser *** emerging technologies enable the vertical smooth sidewalls needed for a successful imprint into thin layers of polymers with aspect ratios exceeding *** with high aspect ratios of up to 28 and no residual layer were produced in ormocers using the micromoulding into capillaries(MIMIC)process with subsequent *** work presents and balances the different fabrication routes and the subsequent generation of working tools from masters with inverted tones and the combination of hard and soft *** provides these techniques with a proof of concept for their compatibility with high volume manufacturing of complex micro-and nanostructures.

关键词： cryo-etching direct 6 write laser lithography high aspect ratio moulding nanoimprint lithography ormocer photonic nanofences 2-photon polymerization

Freeze-thaw cycles and associated geomorphology in a post-glacial environment:current glacial,paraglacial,periglacial and proglacial scenarios at Pico de orizaba volcano,Mexico

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Journal of Mountain Science 2024年第6期21卷 1954-1977页

作者： v.ctor SoTo Carlos M.WELSH R. Kenji YoSHIKAWA Hugo DELGADo GRANADoS Centro de Ciencias de la Tierra Universidad VeracruzanaCircuito Gonzalo Aguirre BeltránS/NZona Universitaria91090XalapaMéxico Water and Environmental Research Center University of Alaska FairbanksFairbanksAlaska 99775USA Instituto de Geofísica Universidad Nacional Autónoma de MéxicoCiudad de México 04150México Department of Earth and Environmental Sciences Ludwig Maximilians UniversitätMunich 80333Germany

The glacial history of Pico de orizaba indicates that during the Last Glacial Maximum,its icecap covered up to~3000 m asl;due to the air temperature increasing,its main glacier has retreated to 5050 m *** retraction of the glacier has left behind an intense climatic instability that causes a high frequency of freeze-thaw cycles of great intensity;the resulting geomorphological processes are represented by the fragmentation of the bedrock that occupies the upper parts of the *** is a notable lack of studies regarding the fragmentation and erosion occurring in tropical high mountains,and the associated geomorphological risks;for this reason,as a first stage of future continuous research,this study analyzes the freezing and thawing cycles that occur above 4000 m asl,through continuous monitoring of surface ground *** results allow us to identify and characterize four zones:glacial,paraglacial,periglacial and *** was found that the paraglacial zone presents an intense drop of temperature,of up to~9℃ in only sixty *** rock fatigue and intense freeze-thaw cycles that occur in this area are responsible for the high rate of rock disintegration and represent the main factor of the constant slope dynamics that occur at the *** activity decreases,both in frequency and intensity,according to the distance to the glacier,which is where the temperature presents a certain degree of stability,until reaching the proglacial zone,where cycles are almost non-existent,and therefore there is no gelifraction *** geomorphological processes have resulted in significant alterations to the mountain slopes,which can have severe consequences in terms of risk and water.

关键词： Freeze-Thaw Gelifraction Mountain mechanical erosion Periglacial geomorphology Postglacial scenarios

Chitosan conduits enriched with fibrin-collagen hydrogel with or without adipose-derived mesenchymal stem cells for the repair of 15-mm-long sciatic nerve defect

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Neural Regeneration Research 2023年第6期18卷 1378-1385页

作者： Marwa El Soury óscar Darío García-García Isabella Tarulli Jesús Chato-Astrain Isabelle Perroteau Stefano Geuna Stefania Raimondo Giovanna Gambarotia v.ctor Carriel Department of Clinical and Biological Sciences University of TorinoTorinoItaly Neuroscience Institute Cavalieri ottolenghi University of TorinoTorinoItaly Department of Histology Tissue Engineering GroupUniversity of GranadaGranadaSpain Instituto de Investigacion Biosanitaria Ibs.GRANADAGranadaSpain

Hollow conduits of natural or synthetic origins have shown acceptable regeneration results in short nerve gap repair;however,results are still not comparable with the current gold standard technique“autografts”.Hollow conduits do not provide a successful regeneration outcome when it comes to critical nerve gap *** the lumen of conduits with different extracellular materials and cells could provide a better biomimicry of the natural nerve regenerating environment and is expected to ameliorate the conduit *** this study,we evaluated nerve regeneration in vivo using hollow chitosan conduits or conduits enriched with fibrin-collagen hydrogels alone or with the further addition of adipose-derived mesenchymal stem cells in a 15 mm rat sciatic nerve transection *** changes in the hydrogel consistency and structural stability in vivo led to a failure of nerve regeneration after 15 ***,the molecular assessment in the early regeneration phase(7,14,and 28 days)has shown an upregulation of useful regenerative genes in hydrogel enriched conduits compared with the hollow *** composed of fibrin-collagen were able to upregulate the expression of soluble NRG1,a growth factor that plays an important role in Schwann cell *** further enrichment with adipose-derived mesenchymal stem cells has led to the upregulation of other important genes such as ErbB2,vEGF-A,BDNF,c-Jun,and ATF3.

关键词： adipose-derived stem cells chitosan conduit fibrin and collagen hydrogel nerve regeneration nerve repair neuregulin 1 peripheral nerve sciatic nerve

Non-Linear Effects in optical Systems by Lie Algebra and Symplectic Mapping

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Journal of Modern Physics 2022年第11期13卷 1314-1323页

作者： v.ctor M. Castañ o Centro de Física Aplicada y Tecnología Avanzada/Secretaría de Desarrollo Institucional Universidad Nacional Autónoma de México Queretaro México

The use of signals of different frequencies determines the geometrical deviation with respect to the optical axes of a given beam. This angle can be determined by Sympletic Map (SM), a powerful and simple mathematical tool for the characterization and construction of images in Geometrical optics. The Sympletic Map constitutes a Lie Group, with an algebra associated: the Lie Algebra. In general, the SM can be expressed as an infinite series, where each term corresponds to different contributions produced by the optical devices that constitute the optical system (lenses, apertures, bandwidth cutoff, etc.). The level of correction to be performed on the image to recover the original object is clear and controllable by SM. This formalism can be extended easily to physical optics to describe diffraction and interference phenomena.

关键词： Symplectic Mapping Geometrical optics Non-Linear Effects

Risk of cancer,with special reference to extra-intestinal malignancies,in patients with inflammatory bowel disease

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World Journal of Gastroenterology 2013年第48期19卷 9359-9365页

作者： Alicia Algaba Iván Guerra ngel Castao Gema de la Poza v.ctor M Castellano Montserrat López Fernando Bermejo Department of Gastroenterology Hospital Universitario de Fuenlabrada 28942 Madrid Spain Department of Pathology Hospital Universitario de Fuenlabrada28942 Madrid Spain

AIM:To determine the incidence and characteristics of intestinal and extra-intestinal cancers among patients with inflammatory bowel disease in a Spanish hospital and to compare them with those of the local ***:This was a prospective,observational,7-year follow-up,cohort *** incidence,incidence rates based on person-years of follow-up and relative risk were calculated for patients with inflammatory bowel disease and compared with the background *** incidence of cancer was determined using a hospital-based data registry from Hospital Universitario de *** data and details about time from diagnosis of inflammatory bowel disease to occurrence of cancer,disease extent,inflammatory bowel disease treatment,cancer therapy and cancer evolution were also collected in the inflammatory bowel disease ***:Eighteen of 590 patients with inflammatory bowel disease developed cancer[cumulative incidence=3%(95%CI:1.58-4.52)vs 2%(95%CI:1.99-2.11)in the background population;RR=1.5;95%CI:0.97-2.29].The cancer incidence among inflammatory bowel disease patients was 0.53%(95%CI:0.32-0.84)per patient-year of *** with inflammatory bowel disease had a significantly increased relative risk of urothelial carcinoma(RR=5.23,95%CI:1.95-13.87),appendiceal mucinous cystadenoma(RR=36.6,95%CI:7.92-138.4),neuroendocrine carcinoma(RR=13.1,95%CI:1.82-29.7)and rectal carcinoid(RR=8.94,95%CI:1.18-59.7).Colorectal cancer cases were not ***:The overall risk of cancer did not significantly increase in our inflammatory bowel disease ***,there was an increased risk of urinary bladder cancer and,with less statistical power,an increased risk of appendiceal mucinous cystadenoma and of neuroendocrine *** cancer risk was low in our series.

关键词： Extra-intestinal cancer Inflammatory bowel disease Cancer risk Background population Urothelial carcinoma Appendiceal mucinous cystadenoma Neuroendocrine carcinoma Rectal carcinoid

Proteomic dynamics revealed sex-biased responses to combined heat-drought stress in Marchantia

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Journal of Integrative Plant Biology 2024年第10期66卷 2226-2241页

作者： Sara Guerrero v.ctor Roces Lara García-Campa Luis valledor Mónica Meijón Department of organisms and Systems BiologyFaculty of Biology/BiotechnologyInstitute of AsturiasUniversity of OviedoOviedoAsturias 33071Spain

Recent studies have documented plant responses to climate change extensively, particularly to single-stress exposures. However, critical factors for stress survival, such as sexual differentiation,are not often considered. The dioicous Marchantia polymorpha stands as an evolutionary milestone,potentially preserving ancestral traits from the early colonizers. In this study, we employed proteomic analyses complemented with physiological monitoring to investigate combined heat and drought responses in Tak-1(male) and Tak-2(female)accessions of this liverwort. Additionally, targeted transcriptomics was conducted using different natural populations from contrasting *** findings revealed sex-biased dynamics among natural accessions, particularly evident under control conditions and during early stress responses. Although Tak-2 exhibited greater diversity than Tak-1 under control conditions, male accession demonstrated distinct and more rapid stress sensing and signaling. These differences in stress response appeared to be strongly related to sex-specific plasticity influenced by geoclimatic origin. Furthermore, we established distinct protein gene ages and genomic distribution trends, underscoring the importance of protein diversification over time. This study provides an evolutionary perspective on sexual divergence and stress emergence employing a systems biology approach, which allowed for the establishment of global and sex-specific interaction networks in the stress response.

关键词： abiotic stress land adaptation liverwort sex-biased response systems biology

Universalities of earthquake-network characteristics

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Chinese Science Bulletin 2011年第34期56卷 3697-3701页

作者： ABE Sumiyoshi PASTN Denisse MUoZ v.ctor SUZUKI Norikazu Department of Physical Engineering Mie University Institut Supérieur des Matériaux et Mécaniques Avancés Departamento de Física Facultad de Ciencias Universidad de Chile College of Science and Technology Nihon University

The scale-free and small-world properties are studied in detail for the complex earthquake networks constructed from the seismic data sets taken from California (USA), Japan, Iran and Chile. It is found that, in all these geographical regions, both the exponent / of the power-law connectivity distribution and the clustering coefficient C take the universal invariant values /≈1 and C≈0.85, respectively, as the cell size, which is the scale of coarse graining needed for construction of network, becomes larger than a certain value. A possible physical interpretation is given to the emergence of such remarkable invariance.

关键词：地震网络普遍性加利福尼亚州构造复杂聚类系数地理区域网络建设物理解释

Mgo-based adsorbents for Co2 adsorption:Influence of structural and textural properties on the Co_2 adsorption performance

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Journal of Environmental Sciences 2017年第7期29卷 418-428页

作者： Gutiérrez-Bonilla Elvira Granados-Correa Francisco Sánchez-Mendieta v.ctor Morales-Luckie Raúl Alberto National Institute of Nuclear Research Department of ChemistryA.P.18-1027Col.EscandonMigud Hidalgo DelegationZip Code 1180 Mexico D.F.Mexico Autonomous University of Mexieo State Faculty of ChemistryColon avenueintersection with ride Tollocan s/n TolucaMexicoMexico

A series of Mgo-based adsorbents were prepared through solution–combustion synthesis and ball-milling *** prepared Mgo-based powders were characterized using X-ray diffraction,scanning electron microscopy,N_2 physisorption measurements,and employed as potential adsorbents for Co_2 *** influence of structural and textural properties of these adsorbents over the Co_2 adsorption behaviour was also *** results showed that Mgo-based products prepared by solution–combustion and ball-milling processes,were highly porous,fluffy,nanocrystalline structures in nature,which are unique physico-chemical properties that significantly contribute to enhance their Co_2 *** was found that the Mgo synthesized by solution combustion process,using a molar ratio of urea to magnesium nitrate（2：1）,and treated by ball-milling during 2.5 hr（Mgo-BM2.5h）,exhibited the maximum Co_2 adsorption capacity of 1.611 mmol/g at 25℃ and 1 atm,mainly via *** Co_2 adsorption behaviour on the Mgo-based adsorbents was correlated to their improved specific surface area,total pore volume,pore size distribution and *** reusability of synthesized Mgo-BM2.5h was confirmed by five consecutive Co_2adsorption–desorption times,without any significant loss of performance,that supports the potential of Mgo-based *** results confirmed that the special features of Mgo prepared by solution–combustion and treated by ball-milling during 2.5 hr are favorable to be used as effective Mgo-based adsorbent in post-combustion Co_2 capture technologies.

关键词： Co_2 adsorption Mgo-based adsorbents Porous materials Solution–combustion synthesis Ball-milling process Textural properties