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排序方式: 共有1622条查询结果,搜索用时 15 毫秒
31.
Joao Felipe Costa 《Computers & Geosciences》2009,35(11):2222-2230
This article investigates an alternative method to deal with data sets in the presence of trends. Median polish kriging (MPK) was introduced as an alternative solution to universal kriging or intrinsic random functions of order k (IRF-k) for estimation in the presence of trends. The maps obtained using the original MPK algorithm show banding artefacts which do not appear in the reference data set. A modified version of MPK was introduced to attempt to remove the banding artefacts. The results confirm the improvement in quality of estimate using the modified version of MPK (called MPKm), which takes into account the problems of clustered samples and boundary effect associated with the re-addition of the trend along bands. The variation introduced in the median polish algorithm proved to be satisfactory in eliminating the artefacts. 相似文献
32.
Universitärer Forschungscluster „Sustainable Technologies in Metal Production and Processing” (STMP)
H. Antrekowitsch H. Biedermann B. Buchmayr F. Ebner W. Eichlseder H. Harmuth W. Kepplinger F. Kessler W. Krieger K. Lorber A. Ludwig 《BHM Berg- und Hüttenm?nnische Monatshefte》2006,151(7):263-266
Foundation of a university research cluster — Co-operation along the value creation chain from raw materials to components — Evidence of joint performance offers — Utilization of synergies — Integration of Christian Doppler Laboratories — Flexible arrangement of co-operations and networks 相似文献
33.
Valeska Ormazabal Estefanía Nova-Lampeti Daniela Rojas Felipe A. Zúiga Carlos Escudero Paola Lagos Alexa Moreno Yanara Pavez Camila Reyes Milly Yez Mabel Vidal Guillermo Cabrera-Vives Katherine Oporto Claudio Aguayo 《International journal of molecular sciences》2022,23(2)
Tissue regeneration is often impaired in patients with metabolic disorders such as diabetes mellitus and obesity, exhibiting reduced wound repair and limited regeneration capacity. We and others have demonstrated that wound healing under normal metabolic conditions is potentiated by the secretome of human endothelial cell-differentiated mesenchymal stem cells (hMSC-EC). However, it is unknown whether this effect is sustained under hyperglycemic conditions. In this study, the wound healing effect of secretomes from undifferentiated human mesenchymal stem cells (hMSC) and hMSC-EC in a type-2 diabetes mouse model was analyzed. hMSC were isolated from human Wharton’s jelly and differentiated into hMSC-EC. hMSC and hMSC-EC secretomes were analyzed and their wound healing capacity in C57Bl/6J mice fed with control (CD) or high fat diet (HFD) was evaluated. Our results showed that hMSC-EC secretome enhanced endothelial cell proliferation and wound healing in vivo when compared with hMSC secretome. Five soluble proteins (angiopoietin-1, angiopoietin-2, Factor de crecimiento fibroblástico, Matrix metallopeptidase 9, and Vascular Endothelial Growth Factor) were enriched in hMSC-EC secretome in comparison to hMSC secretome. Thus, the five recombinant proteins were mixed, and their pro-healing property was evaluated in vitro and in vivo. Functional analysis demonstrated that a cocktail of these proteins enhanced the wound healing process similar to hMSC-EC secretome in HFD mice. Overall, our results show that hMSC-EC secretome or a combination of specific proteins enriched in the hMSC-EC secretome enhanced wound healing process under hyperglycemic conditions. 相似文献
34.
Deiweson Souza-Monteiro Mrcia Cristina dos Santos Guerra Leonardo Oliveira Bittencourt Walessa Alana Bragana Arago Aline Dionizio Felipe Martins Silveira Marília Afonso Rebelo Buzalaf Manoela Domingues Martins Maria Elena Crespo-Lopez Rafael Rodrigues Lima 《International journal of molecular sciences》2022,23(4)
Aluminum (Al) is one of the most abundant elements on Earth, and its high extraction rate and industrial use make human exposure very common. As Al may be a human toxicant, it is important to investigate the effects of Al exposure, mainly at low doses and for prolonged periods, by simulating human exposure. This work aimed to study the effects of low-dose exposure to chloride aluminum (AlCl3) on the oxidative biochemistry, proteomic profile, and morphology of the major salivary glands. Wistar male rats were exposed to 8.3 mg/kg/day of AlCl3 via intragastric gavage for 60 days. Then, the parotid and submandibular glands were subjected to biochemical assays, proteomic evaluation, and histological analysis. Al caused oxidative imbalance in both salivary glands. Dysregulation of protein expression, mainly of those related to cytoarchitecture, energy metabolism and glandular function, was detected in both salivary glands. Al also promoted histological alterations, such as acinar atrophy and an increase in parenchymal tissue. Prolonged exposure to Al, even at low doses, was able to modulate molecular alterations associated with morphological impairments in the salivary glands of rats. From this perspective, prolonged Al exposure may be a risk to exposed populations and their oral health. 相似文献
35.
Anna Broto-Ribas Claudia Vignatti Alicia Jimenez-Almarza Javier Luis-Barrera Zahra Dolatkhah Felipe Gandara Inhar Imaz Ruben Mas-Balleste Jose Aleman Daniel Maspoch 《Nano Research》2021,14(2):458-465
A well-established strategy to synthesize heterogeneous,metal-organic framework(MOF)catalysts that exhibit nanoconfinement effects,and specific pores with highly-localized catalytic sites,is to use organic linkers containing organocatalytic centers.Here,we report that by combining this linker approach with reticular chemistry,and exploiting three-dimensioanl(3D)MOF-structural data from the Cambridge Structural Database,we have designed four heterogeneous MOF-based catalysts for standard organic transformations.These programmable MOFs are isoreticular versions of pcu IRMOF-16,feu UiO-68 and pillared-pcu SNU-8X,the three most common topologies of MOFs built from the organic linker p.p'-terphenyldicarboxylic acid(tpdc).To synthesize the four squaramide-based MOFs,we designed and synthesized a linker,4,4’-((3,4-dioxocyclobut-1-ene-1,2-diyl)bis(azanedyil))dibenzoic acid(Sq_tpdc),which is identical in directionality and length to tpdc but which contains organocatalytic squaramide centers.Squaramides were chosen because their immobilization into a framework enhances its reactivity and stability while avoiding any self-quenching phenomena.Therefore,the four MOFs share the same organocatalytic squaramide moiety,but confine it within distinct pore environments.We then evaluated these MOFs as heterogeneous H-bonding catalysts in organic transformations:a Friedel-Crafts alkylation and an epoxide ring-opening.Some of them exhibited good performance in both reactions but all showed distinct catalytic profiles that reflect their structural differences. 相似文献
36.
G. Kessler 《Progress in Nuclear Energy》2002,40(3-4):309-325
Nuclear energy must compete against other energy technologies in the 21st century. It must be economical and it must be proven that it fulfills the conditions for sutainability. This means that the requirements of — no short term depletion of resources — extremely low emission of noxious or radioactive substances to the environment — extremely low release of radioactivity from a nuclear plant in case of the most severe accidents and — the present very long term problem of high active waste must be transformed into a few hundred years problem through destruction of plutonium, transmutation of the minor actinides and the most important very long lived fission products. 相似文献
37.
R. Schneider J. Weder U. Coors G. -W. v. Rymon Lipinski R. Wittmann S. Wegner-Hambloch H. G. Kessler F. Ledl A. Rapp R. Frommberger Th. Täubert A. Rohrdanz D. Ehlermann D. v. Wachtendonk H. Weisser S. Scherer W. Ruge H. Klostermeyer H. Rehbein M. Miller H. G. Maier W. Feldheim F. Kiermeier J. Buchberger 《European Food Research and Technology》1991,193(6):566-574
38.
Jesus E. Molinar-Solis Felipe Gomez-Castaneda Jose A. Moreno-Cadenas Victor H. Ponce-Ponce 《The Journal of VLSI Signal Processing》2007,49(1):207-216
At present, the Cellular Neural Network (CNN) is a potential parallel structure able to perform image processing tasks in
real-time when is effectively implemented in CMOS technology. The CNN silicon integration success is due mainly to the local
connectivity of processing cells. In this work, an alternative design based on floating-gate MOS inverters is presented, which
uses unipolar signals for solving binary tasks. The approach brings a fast response in a reduced silicon area, as shown through
electrical simulations. A prototype cell in CMOS technology (AMI, 1.2 micron) was fabricated and tested for eight image processing
tasks.
相似文献
Victor H. Ponce-Ponce |
39.
R Baumgart A Betz S Kessler M Kettler L Schweiberer 《Canadian Metallurgical Quarterly》1994,23(6):396-403
The importance of the functional unit "bone-soft-tissue" for the treatment of bone defects is discussed. A division is made between non-vascular and vascular bone transport. The individual methods are explained and their clinical significance is illustrated partly using case material. In general, the best way to fill small defects in vital soft tissue is to use cancellous autografts. For bridging longer bone defects callus distraction is the method of first choice, but in individual cases vascularized bone transfer can be taken from the iliac crest or the fibula. Homo- or heterografts should only be used in cases where no autologic bone material is available or when there is not enough. 相似文献
40.
Felipe Herrera 《JOM Journal of the Minerals, Metals and Materials Society》1963,15(6):443-445
Revolutionary developments in the patterns of world trade have taken place during the past five years, and Latin America is no exception. This article discusses the effects of the Latin American Free Trade Association, the Central American Common Market, and the Inter-American Development Bank on the economic integration of Latin America. 相似文献