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1.
Aard J. Groen Petra C. De WeerdNederhof Inge C. Kerssensvan Drongelen Rob A.J. Badoux Gerard P.H. Olthuis 《Creativity & Innovation Management》2002,11(1):2-16
In this paper we describe a framework for analysing the creation and justification of Research & Development. The 4S framework is developed for analysing the scope, scale, skills and social network aspects of Research & Development value. The framework is based on social system theory, a process contingency model, and recent Research & Development metrics. We present a first empirical assessment based on a workshop using the 4S framework for leveraging Research & Development. Results that assist in the assessment of value creation utilising R & D within networks are very relevant in high tech industries. The multi–dimensional process approach of this framework seems promising for understanding and managing R&D value creation, but needs further operationalisation. Case studies are described and a Dutch network on leveraging R&D has been initiated. 相似文献
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Vita etraj
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Drago Ksenija Strojnik Gaper Klan
ar Petra kerl Vida Stegel Ana Blatnik Marta Banjac Mateja Krajc Srdjan Novakovi 《International journal of molecular sciences》2022,23(13)
Pathogenic/likely pathogenic variants in susceptibility genes that interrupt RNA splicing are a well-documented mechanism of hereditary cancer syndromes development. However, if RNA studies are not performed, most of the variants beyond the canonical GT-AG splice site are characterized as variants of uncertain significance (VUS). To decrease the VUS burden, we have bioinformatically evaluated all novel VUS detected in 732 consecutive patients tested in the routine genetic counseling process. Twelve VUS that were predicted to cause splicing defects were selected for mRNA analysis. Here, we report a functional characterization of 12 variants located beyond the first two intronic nucleotides using RNAseq in APC, ATM, FH, LZTR1, MSH6, PALB2, RAD51C, and TP53 genes. Based on the analysis of mRNA, we have successfully reclassified 50% of investigated variants. 25% of variants were downgraded to likely benign, whereas 25% were upgraded to likely pathogenic leading to improved clinical management of the patient and the family members. 相似文献
5.
Iris Miescher Petra Wolint Christine Opelz Jess G. Snedeker Pietro Giovanoli Maurizio Calcagni Johanna Buschmann 《International journal of molecular sciences》2022,23(14)
(1) Background: Surgical tendon repair often leads to adhesion formation, leading to joint stiffness and a reduced range of motion. Tubular implants set around sutured tendons might help to reduce peritendinous adhesions. The lubricant hyaluronic acid (HA) is a viable option for optimizing such tubes with the goal of further enhancing the anti-adhesive effect. As the implant degrades over time and diffusion is presumed, the impact of HA on tendon cells is important to know. (2) Methods: A culture medium of rabbit Achilles tenocytes was supplemented with high-molecular-weight (HMW) HA and the growth curves of the cells were assessed. Additionally, after 3, 7 and 14 days, the gene expression of several markers was analyzed for matrix assembly, tendon differentiation, fibrosis, proliferation, matrix remodeling, pro-inflammation and resolution. (3) Results: The addition of HA decreased matrix marker genes, downregulated the fibrosis marker α-SMA for a short time and slightly increased the matrix-remodeling gene MMP-2. Of the pro-inflammatory marker genes, only IL-6 was significantly upregulated. IL-6 has to be kept in check, although IL-6 is also needed for a proper initial inflammation and efficient resolution. (4) Conclusions: The observed effects in vitro support the intended anti-adhesion effect and therefore, the use of HMW HA is promising as a biodegradable implant for tendon repair. 相似文献
6.
A. V. Shlyakhtina S. N. Savvin A. V. Levchenko A. V. Knotko Petra Fedtke Andreas Busch Torsten Barfels Marion Wienecke L. G. Shcherbakova 《Journal of Electroceramics》2010,24(4):300-307
The electrical conductivity of new solid electrolytes Eu2.096Hf1.904O6.952 and Gd2Hf2O7 have been compared with those for different pyrochlores including titanates and zirconates Ln2+xМ2−xO7−δ (Ln = Sm-Lu; M = Ti, Zr; x = 0−0.81). Impedance spectroscopy data demonstrate that Eu2.096Hf1.904O6.952 and Gd2Hf2O7 synthesized from mechanically activated oxides have high ionic conductivity, comparable to that of their zirconate analogues.
The bulk and grain-boundary components of conductivity in Sm2.096Hf1.904O6.952 (Тsynth = 1600oС), Eu2.096Hf1.904O6.952 and Gd2Hf2O7 (Тsynth = 1670oС) have been determined. The highest bulk conductivity is offered by the disordered pyrochlores prepared at 1600oC
and 1670oC: ~1.5 × 10−4 S/cm for Sm2.096Hf1.904O6.952, 5 × 10−3 S/cm for Eu2.096Hf1.904O6.952 and 3 × 10−3 S/cm for Gd2Hf2O7 at 780oС, respectively. The conductivity of the fluorite-like phases at the phase boundaries of the Ln2+xМ2−xO7−δ (Ln = Eu, Gd; M = Zr, Hf; x ~ 0.286) solid solutions, as well as that of the high-temperature fluorite-like phases Ln2+xМ2−xO7−δ (Ln = Eu, Gd; M = Zr, Hf; x = 0−0.286), is lower than the conductivity of the disordered pyrochlores Ln2+xМ2−xO7−δ (Ln = Eu, Gd; M = Zr, Hf; x = 0−0.096). 相似文献
7.
Nanotwin formation and its physical properties and effect on reliability of copper interconnects 总被引:1,自引:0,他引:1
Di Xu Vinay Sriram Jenn-Ming Yang Gery R. Stafford Inka Zienert Petra Hofmann 《Microelectronic Engineering》2008,85(10):2155-2158
Ultra-fine grained copper with a large amount of nano-scale twin boundaries has high mechanical strength and maintains normal electrical conductivity. The combination of these properties may lead to promising applications in future Si microelectronic technology, especially as interconnect material for air-gap and free-standing copper technologies. Based on first principles calculations of total energy and in-situ stress measurements, high stress followed by stress relaxation during the Cu film deposition seems to have contributed to nanotwin formation. Nanoindentation studies have shown a larger hardness for copper with a higher nanotwin density. The effect of Cu nanotwin boundaries on grain growth was investigated by scanning electron microscopy (SEM), electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM). The presence of a high density of nanotwin boundaries may improve the reliability of Cu interconnects. 相似文献
8.
Konstantinos Spyrou Matteo Calvaresi Evmorfia K. Diamanti Theodoros Tsoufis Dimitrios Gournis Petra Rudolf Francesco Zerbetto 《Advanced functional materials》2015,25(2):263-269
Experimental and theoretical studies are performed in order to illuminate, for first time, the intercalation mechanism of polycyclic aromatic molecules into graphite oxide. Two representative molecules of this family, aniline and naphthalene amine are investigated. After intercalation, aniline molecules prefer to covalently connect to the graphene oxide matrix via chemical grafting, while napthalene amine molecules bind with the graphene oxide surface through π–π interactions. The presence of intercalated aromatic molecules between the graphene oxide layers is demonstrated by X‐ray diffraction, while the type of interaction between graphene oxide and polycyclic organic molecules is elucidated by X‐ray photoelectron spectroscopy. Combined quantum mechanical and molecular mechanical calculations describe the intercalation mechanism and the aniline grafting, rationalizing the experimental data. The present work opens new perspectives for the interaction of various aromatic molecules with graphite oxide and the so‐called “intercalation chemistry”. 相似文献
9.
Hanna Mannell Petra Kameritsch Heike Beck Alexander Pfeifer Ulrich Pohl Kristin Pogoda 《International journal of molecular sciences》2022,23(1)
The gap junction protein connexin 43 (Cx43) is associated with increased cell migration and to related changes of the actin cytoskeleton, which is mediated via its C-terminal cytoplasmic tail and is independent of its channel function. Cx43 has been shown to possess an angiogenic potential, however, the role of Cx43 in endothelial cell migration has not yet been investigated. Here, we found that the knock-down of Cx43 by siRNA in human microvascular endothelial cells (HMEC) reduces migration, as assessed by a wound assay in vitro and impaired aortic vessel sprouting ex vivo. Immunoprecipitation of Cx43 revealed an interaction with the tyrosine phosphatase SHP-2, which enhanced its phosphatase activity, as observed in Cx43 expressing HeLa cells compared to cells treated with an empty vector. Interestingly, the expression of a dominant negative substrate trapping mutant SHP-2 (CS) in HMEC, via lentiviral transduction, also impaired endothelial migration to a similar extent as Cx43 siRNA compared to SHP-2 WT. Moreover, the reduction in endothelial migration upon Cx43 siRNA could not be rescued by the introduction of a constitutively active SHP-2 construct (EA). Our data demonstrate that Cx43 and SHP-2 mediate endothelial cell migration, revealing a novel interaction between Cx43 and SHP-2, which is essential for this process. 相似文献
10.
Emese Rka Blint Gabriella Fr Balzs Kui Zsolt Balla Eszter Sra Kormnyos Erik Mrk Orjn Brigitta Tth Gyngyi Horvth Edina Szcs Sndor Benyhe Eszter Ducza Petra Pallagi Jzsef Malth Viktria Venglovecz Pter Hegyi Lrnd Kiss Zoltn Rakonczay Jr. 《International journal of molecular sciences》2022,23(3)
Opioids are widely used for the pain management of acute pancreatitis (AP), but their impact on disease progression is unclear. Therefore, our aim was to study the effects of clinically relevant opioids on the severity of experimental AP. Various doses of fentanyl, morphine, or buprenorphine were administered as pre- and/or post-treatments in rats. Necrotizing AP was induced by the intraperitoneal injection of L-ornithine-HCl or intra-ductal injection of Na-taurocholate, while intraperitoneal caerulein administration caused edematous AP. Disease severity was determined by laboratory and histological measurements. Mu opioid receptor (MOR) expression and function was assessed in control and AP animals. MOR was expressed in both the pancreas and brain. The pancreatic expression and function of MOR were reduced in AP. Fentanyl post-treatment reduced necrotizing AP severity, whereas pre-treatment exacerbated it. Fentanyl did not affect the outcome of edematous AP. Morphine decreased vacuolization in edematous AP, while buprenorphine pre-treatment increased pancreatic edema during AP. The overall effects of morphine on disease severity were negligible. In conclusion, the type, dosing, administration route, and timing of opioid treatment can influence the effects of opioids on AP severity. Fentanyl post-treatment proved to be beneficial in AP. Clinical studies are needed to determine which opioids are best in AP. 相似文献