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排序方式: 共有161条查询结果,搜索用时 218 毫秒
41.
The digitalization of invoice processes provides a good opportunity for companies to pare down expenses, optimize administrative tasks, and increase efficiency and competitiveness. But the digitalization is limited by a variety of software solutions, legal uncertainties, heterogeneous demands, lack of know-how, and information system infrastructure incompatibilities. A holistic map of electronic invoice processes is mandatory, especially to demonstrate different levels of process integration and optimization. A maturity model puts this into practice and provides companies with a tool to identify their current situation and to derive recommendations to optimize that situation. In this paper, a maturity model for electronic invoice processes will be developed using exploratory data from focus groups. A theoretical approach that is based on a procedure-model for developing maturity models is applied. Four categories (strategy, acceptance, processes & organization, and technology) are identified and enriched by sub-categories. Future research requires the development of detailed maturity metrics. 相似文献
42.
Marta Colletti Angela Galardi Evelina Miele Virginia Di Paolo Ida Russo Cristiano De Stefanis Rita De Vito Martina Rinelli Andrea Ciolfi Biagio De Angelis Angelica Zin Alessandro Guffanti Maria Cristina Digilio Antonio Novelli Rita Alaggio Giuseppe Maria Milano Angela Di Giannatale 《International journal of molecular sciences》2021,22(11)
43.
Angelica Judith Granados López Jesús Adrián López 《International journal of molecular sciences》2014,15(9):15700-15733
Aberrant miRNA expression is well recognized as an important step in the development of cancer. Close to 70 microRNAs (miRNAs) have been implicated in cervical cancer up to now, nevertheless it is unknown if aberrant miRNA expression causes the onset of cervical cancer. One of the best ways to address this issue is through a multistep model of carcinogenesis. In the progression of cervical cancer there are three well-established steps to reach cancer that we used in the model proposed here. The first step of the model comprises the gene changes that occur in normal cells to be transformed into immortal cells (CIN 1), the second comprises immortal cell changes to tumorigenic cells (CIN 2), the third step includes cell changes to increase tumorigenic capacity (CIN 3), and the final step covers tumorigenic changes to carcinogenic cells. Altered miRNAs and their target genes are located in each one of the four steps of the multistep model of carcinogenesis. miRNA expression has shown discrepancies in different works; therefore, in this model we include miRNAs recording similar results in at least two studies. The present model is a useful insight into studying potential prognostic, diagnostic, and therapeutic miRNAs. 相似文献
44.
Angelica Niazov‐Elkan Haim Weissman Sounak Dutta Sidney R. Cohen Mark A. Iron Iddo Pinkas Tatyana Bendikov Boris Rybtchinski 《Advanced materials (Deerfield Beach, Fla.)》2018,30(2)
Organic crystalline materials are used as dyes/pigments, pharmaceuticals, and active components of photonic and electronic devices. There is great interest in integrating organic crystals with inorganic and carbon nanomaterials to create nanocomposites with enhanced properties. Such efforts are hampered by the difficulties in interfacing organic crystals with dissimilar materials. Here, an approach that employs organic nanocrystallization is presented to fabricate solution‐processed organic nanocrystal/carbon nanotube (ONC/CNT) hybrid materials based on readily available organic dyes (perylene diimides (PDIs)) and carbon nanotubes. The hybrids are prepared by self‐assembly in aqueous media to afford free‐standing films with tunable CNT content. These exhibit excellent conductivities (as high as 5.78 ± 0.56 S m?1), and high thermal stability that are superior to common polymer/CNT hybrids. The color of the hybrids can be tuned by adding various PDI derivatives. ONC/CNT hybrids represent a novel class of nanocomposites, applicable as optoelectronic and conductive colorant materials. 相似文献
45.
Branco É Cabral R Gomes BD Kfoury JR Miglino MA 《Microscopy research and technique》2012,75(7):917-920
Bone marrow is a source of stem cells for greater and easier access, which is widely studied as a provider of hematopoietic and mesenchymal cells for various purposes, mainly therapeutic by the advances in research involving cell therapy. The swine is an animal species commonly used in the pursuit of development of experimental models. Thus, this study aimed to standardize protocol for collection and separation of bone marrow in swines, since this species is widely used as experimental models for various diseases. Twelve animals were used, which underwent bone marrow puncture with access from the iliac crest and cell separation by density gradient followed by a viability test with an average of 98% of viable cells. Given our results, we can ensure the swine as an excellent model for obtaining and isolation of mononuclear cells from bone marrow, stimulating several studies addressing the field of cell therapy. 相似文献
46.
Kenny Man Inês A. Barroso Mathieu Y. Brunet Ben Peacock Angelica S. Federici David A. Hoey Sophie C. Cox 《International journal of molecular sciences》2022,23(2)
Extracellular vesicles (EVs) have garnered growing attention as promising acellular tools for bone repair. Although EVs’ potential for bone regeneration has been shown, issues associated with their therapeutic potency and short half-life in vivo hinders their clinical utility. Epigenetic reprogramming with the histone deacetylase inhibitor Trichostatin A (TSA) has been reported to promote the osteoinductive potency of osteoblast-derived EVs. Gelatin methacryloyl (GelMA) hydrogels functionalised with the synthetic nanoclay laponite (LAP) have been shown to effectively bind, stabilise, and improve the retention of bioactive factors. This study investigated the potential of utilising a GelMA-LAP hydrogel to improve local retention and control delivery of epigenetically enhanced osteoblast-derived EVs as a novel bone repair strategy. LAP was found to elicit a dose-dependent increase in GelMA compressive modulus and shear-thinning properties. Incorporation of the nanoclay was also found to enhance shape fidelity when 3D printed compared to LAP-free gels. Interestingly, GelMA hydrogels containing LAP displayed increased mineralisation capacity (1.41-fold) (p ≤ 0.01) over 14 days. EV release kinetics from these nanocomposite systems were also strongly influenced by LAP concentration with significantly more vesicles being released from GelMA constructs as detected by a CD63 ELISA (p ≤ 0.001). EVs derived from TSA-treated osteoblasts (TSA-EVs) enhanced proliferation (1.09-fold), migration (1.83-fold), histone acetylation (1.32-fold) and mineralisation (1.87-fold) of human bone marrow stromal cells (hBMSCs) when released from the GelMA-LAP hydrogel compared to the untreated EV gels (p ≤ 0.01). Importantly, the TSA-EV functionalised GelMA-LAP hydrogel significantly promoted encapsulated hBMSCs extracellular matrix collagen production (≥1.3-fold) and mineralisation (≥1.78-fold) in a dose-dependent manner compared to untreated EV constructs (p ≤ 0.001). Taken together, these findings demonstrate the potential of combining epigenetically enhanced osteoblast-derived EVs with a nanocomposite photocurable hydrogel to promote the therapeutic efficacy of acellular vesicle approaches for bone regeneration. 相似文献
47.
Elastic-plastic material properties for HVOF sprayed Ti2AlC (sprayed with Maxthal 211 powder) and plasma sprayed NiCoCrAlY coatings were investigated using modeling and experimental
Berkovich microindentation. Optical microstructure evaluations were also performed. The theories of Hertz, Oliver and Pharr
were combined with finite element analysis for extracting the material properties. Empirically based material models for both
thermal sprayed Ti2AlC and NiCoCrAlY coatings are proposed. 相似文献
48.
Maria Cazacu Angelica Vlad Anton Airinei Mihaela Alexandru 《Polymer International》2008,57(9):1067-1074
BACKGROUND: Because of its properties, silica gel is an excellent host for different compounds. Many types of chemical species (organics, organometallics, proteins, enzymes, etc.) can be encapsulated in xerogels, and the sol–gel technique has been shown to be very useful for this aim. RESULTS: Some host–guest systems based on silica and complexed lanthanum were prepared in order to develop fluorescence properties. Three pathways were used to prepare such systems: (1) obtaining the lanthanum complex with a dimethylsiloxane‐based ligand and its incorporation into a silica network; (2) preparation of a silica network having hydroxyazomethine groups and in situ lanthanum complexation; and (3) preparation of polydimethylsiloxane (PDMS)/silica composites that possess hydroxyazomethine groups on the silica and in situ lanthanum complexation. The sol–gel technique was used in all cases. CONCLUSION: The photophysical properties of the prepared compounds were evaluated using fluorescence spectroscopy. The investigations revealed that the systems belonging to the second series are the most fluorescent. In the third series, the presence of PDMS provokes a decrease of the fluorescence intensity, until its complete quenching when the PDMS content exceeds a certain threshold value. However, there is a range of silica/PDMS ratio for which fluorescent free‐standing films can be obtained. The presence of complexed lanthanum induces changes in the morphology of the silica/PDMS matrix, as evidenced by scanning electron microscopy studies. Copyright © 2008 Society of Chemical Industry 相似文献
49.
S Fasth S Filipsson L Hultén J Lindhagen C Ahrén 《Canadian Metallurgical Quarterly》1976,73(28-29):2481-2483
50.
Mayela De la Cruz-Guzman Angelica Aguilar-Aguilar Luis Hernandez-Adame Alan Ba?uelos-Frias Francisco J Medellín-Rodríguez Gabriela Palestino 《Nanoscale research letters》2014,9(1):431
A rhodamine organosilane derivative (Rh-UTES) has been obtained by one-pot synthesis. The chemical structure of Rh-UTES was confirmed by nuclear magnetic resonance (NMR) and infrared (FTIR) techniques. To obtain an inorganic-organic hybrid sensor, Rh-UTES was covalently immobilized on a porous silicon microcavity (PSiMc) via triethoxysilane groups. The attachment of the organic derivative into PSiMc was confirmed by FTIR, specular reflectance, and scanning electron microscopy (SEM). The optical performance of Rh-UTES receptor for Hg2+ detection was investigated by fluorescent spectroscopy and microscopy. Upon the addition of increasing amounts of Hg2+ ions, a remarkable enhancement in emission intensity was produced in both systems. In the solid phase, an increase of integrated fluorescent emission of 0.12- and 0.15-fold after Hg2+ receptor coordination was observed. The light harvesting capability of PSiMc devices allowed obtaining an enhanced fluorescent emission after Rh-UTES immobilization (277-fold). The fluorescence microscopy of hybrid PSiMc sensor provided an optical qualitative test for Hg2+ detection. 相似文献