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121.
Intellectual property (IP) ownership aggressiveness constitutes an organization's strategic stance that prioritizes its IP protection. An organization thus pursues a rigid approach to protect its background IP and strives for exclusive ownership of the foreground IP that results from collaborative projects. This paper investigates how firms' IP ownership aggressiveness influences university–industry collaboration (UIC) project success and examines if the relationship is contingent on the governance modes that firms employ in UICs, especially the intensity of contract formality and shared governance. Analysing survey data from UIC projects of medium‐sized to large firms covering four industries, we find that the levels of contract formality and shared governance moderate the effect of firms' IP ownership aggressiveness on project success. Strong contract formality leads to a negative relationship between firms' IP ownership aggressiveness and UIC project success. Conversely, if firms apply strong shared governance, the relationship between IP ownership aggressiveness and UIC project success is positive. Given firms' strategic approach to protect background IP and claim ownership of foreground IP, these results have implications for UIC managers when selecting governance modes to best support UIC project success. 相似文献
122.
It has been postulated that males of a number of scorpionfly species produce sex pheromones. This is based on the observation
that females often respond only to conspecific males when they evert their genital pouch, the proposed site of pheromone release.
In this study, we prove that in Panorpa germanica (Mecoptera, Panorpidae), the eversion of a male’s genital pouch is associated with the release of a volatile sex pheromone.
In dual choice situations, females showed a high preference for ‘calling’ (males with everted genital pouch) over noncalling
individuals. Volatiles emitted by males and females were collected and identified by coupled gas chromatography–mass spectrometry.
Two aldehydes [(2E,6Z)-nona-2,6-dienal and (E)-non-2-enal] were characteristic of calling males but not of noncalling or immature males or females. Bioassays with synthetic
compounds confirmed that the identified substances are attractive to females. To the best of our knowledge, this is the first
identification of a sex pheromone in scorpionflies. 相似文献
123.
This study examined the signal transduction pathway(s) leading to phosphorylation of p38 in human neutrophils stimulated with lipopolysaccharide and formyl peptides. Blockade of the nitric oxide (NO) pathway in neutrophils with the NO synthase inhibitor N-nitro-L-arginine methyl ester or by treatment with the NO scavenger 2-phenyl-tetramethylimidazoline-1-oxyl-3-oxide attenuated phosphorylation of the mitogen-activated protein kinase p38 in response to lipopolysaccharide but not fMet-Leu-Phe. Using the NO releasing agents S-nitroso-N-acetylpenicillamine and sodium nitroprusside it was determined that nitric oxide is sufficient to cause an increase in phosphorylation of p38. Increasing cellular cGMP with phosphodiesterase inhibitors, by stimulation of soluble guanylyl cyclase with YC-1 or with exogenous dibutyryl cGMP resulted in mitogen-activated protein kinase/extracellular signal-regulated kinase kinase 3,6 (MEK3,6) activation and phosphorylation of p38. This phenomenon was specific for MEK3,6, because these agents had no effect on the phosphorylation state of MEK1,2. A role for protein kinase G but not protein kinase A downstream of lipopolysaccharide but not formylmethionylleucylphenylalanine was shown using the specific inhibitors KT5823 and H89, respectively. These data indicate that activation of p38 by fMet-Leu-Phe and lipopolysaccharide involve different mechanisms, and that activation of protein kinase G by NO-dependent stimulation of guanylyl cyclase is necessary and sufficient for phosphorylation of p38 downstream of lipopolysaccharide. 相似文献
124.
Heping Chen Jianjun Wang George Zhang Thomas Fuhlbrigge Soenke Kock 《The International Journal of Advanced Manufacturing Technology》2009,45(9-10):999-1006
Industrial robots can be made compliant to the environment when the control loop gains are reduced, creating a so-called soft servo capability. This allows industrial robots to be used for assemblies with limited contact requirements. In this paper, we propose an assembly method using soft servo to perform certain assembly tasks where part location errors typically require the use of force control or remote center of compliance (RCC) methods. A typical industrial application, valve body assembly, was used to validate the developed method. This assembly was chosen because it is simple, yet requires compliance in all directions. Lab experiments were performed and the assembly operations were consistently successful enough to show that the developed soft servo strategy can perform certain assembly tasks with small part location errors. Therefore, the soft servo strategy may open a new door for low-cost industrial assembly. Experiments with force control were also performed to compare the performance between soft servo and force control. We found that the force control method is much more sensitive to environmental contact, that the contact forces can be controlled directly, and that greater part location errors can be tolerated. Conversely, assembly with soft servo may either fail to assemble the parts or generate bigger contact forces than allowed. Thus, applications of soft servo are more limited while force control can be successfully used in most all applications. Further investigation is needed to determine the practical industrial use of soft servo for particular types of precision assembly. 相似文献
125.
S. Hamann M.E. Gruner S. Irsen J. Buschbeck C. Bechtold I. Kock S.G. Mayr A. Savan S. Thienhaus E. Quandt S. Fähler P. Entel A. Ludwig 《Acta Materialia》2010,58(18):5949-5961
A new ferromagnetic shape memory thin film system, Fe–Pd–Cu, was developed using ab initio calculations, combinatorial fabrication and high-throughput experimentation methods. Reversible martensitic transformations are found in extended compositional regions, which have increased fcc–fct transformation temperatures in comparison to previously published results. High resolution transmission electron microscopy verified the existence of a homogeneous ternary phase without precipitates. Curie temperature, saturation polarization and orbital magnetism are only moderately decreased by alloying with nonmagnetic Cu. Compared to the binary system; enhanced Invar-type thermal expansion anomalies in terms of an increased volume magnetostriction are predicted. Complementary experiments on splat-fabricated bulk Fe–Pd–Cu samples showed an enhanced stability of the disordered transforming Fe70Pd30 phase against decomposition. From the comparison of bulk and thin film results, it can be inferred that, for ternary systems, the Fe content, rather than the valence electron concentration, should be regarded as the decisive factor determining the fcc–fct transformation temperature. 相似文献
126.
127.
Muoki PN de Kock HL Emmambux MN 《Journal of the science of food and agriculture》2012,92(8):1771-1779
BACKGROUND: The nutritional quality of cassava complementary porridge was improved through extrusion cooking and compositing with either defatted or full fat soy flour (65:35 w/w), and product acceptability by mothers with children of the target population was evaluated. RESULTS: The protein digestibility‐corrected amino acid score (PDCAAS) of extrusion‐ and conventionally cooked composite porridges was within the recommendations for complementary foods. The kinetics of starch digestibility showed that all porridges had a rapid rate of starch digestibility, but the rate was lower when defatted soy flour was added and lowest when full fat soy flour was added. The formation of amylase‐lipid complexes as shown by X‐ray diffraction and differential scanning calorimetry can be attributed to the lower digestibility of extrusion‐cooked porridge with full fat soy flour. If fed thrice per day, extrusion‐cooked porridge with defatted or full fat soy flour would meet the energy, protein and available lysine requirements of a child aged 6–8 months receiving low or average nutrients from breast milk. All porridges were well received by Mozambican mothers who use cassava as a staple food. The mean scores for sensory liking of all porridges were 3 and above on a five‐point hedonic scale. CONCLUSION: Extrusion‐cooked cassava/soy flour porridges have good potential for use as high‐energy/high‐protein complementary foods and have acceptable sensory properties. Copyright © 2012 Society of Chemical Industry 相似文献
128.
129.
Hair, muscle, and liver mercury concentrations were determined in river otter (Lutra canadensis) carcasses collected from the lower coastal plain and piedmont of Georgia. Mean muscle and hair mercury concentrations were greater (P < 0.001) in otters from the lower coastal plain (4.42 and 24.25 mg/kg wet wt, respectively) compared to otters from the piedmont (1.48 and 15.24 mg/kg, respectively). Liver tissue from lower coastal plain otters averaged 7.53 mg/kg mercury. Mean fetus brain and muscle mercury concentrations were 1.03 and 1.58 mg/kg wet wt, respectively, and fetal muscle mercury concentrations were correlated (r = 0.92) with maternal muscle mercury concentrations. Comparison of mercury concentrations found in Georgia otters to those associated with adverse effects in otter and mink (Mustela vison), indicate sublethal contamination with concentrations in some individuals approaching that observed in experimentally dosed individuals that developed clinical signs of mercurialism. Mercury concentrations in fish from the lower coastal plain approached or exceeded concentrations demonstrated to be toxic to experimentally dosed otters. 相似文献
130.
Post-traumatic seizures are a well-recognized complication of head injury; however, the issue of seizure risk assessment remains controversial. The authors present a critical review of the literature pertaining to post-traumatic seizures, with particular emphasis on current concepts of definitions, incidence and risk factors. Different methods of risk assessment are reviewed and the possibility of utilizing functional imaging techniques for seizure risk assessment is also explored. 相似文献