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61.
Olaf A.M. Fisscher Klaasjan Visscher Alan Pearson Ursula Weisenfeld 《Creativity & Innovation Management》2001,10(4):251-258
Research and development departments in industrial firms may not take it for granted anymore that they are the only preferred supplier of research and development to the company of which they are a part. The growing need to be innovative and the increasing availability of innovative competencies on the market result in a pressure on these departments to become more business–like and to reconsider their sources of competitive advantage over other (potential) suppliers of research and development. Traditionally, scientific and technological knowledge and skills concerning the product were the prime source. Nowadays, managerial competencies and the ability to work for and with your clients and suppliers are becoming more important. To become a competitive business in a business, research and development departments should create the competencies that enable them to create value for their clients. This calls for good competence management, comprising management of human resources, information technology, and internal and external interfaces. In this paper we explore what it means and what it takes for research and development departments to implement competence management, elaborating it theoretically and describing a case of competence management in the research and development department of a European car company. 相似文献
62.
Kirsti Rouvinen-Watt Anne-Mari Mustonen Rebecca Conway Catherine Pal Lora Harris Seppo Saarela Ursula Strandberg Petteri Nieminen 《Lipids》2010,45(2):111-128
Hepatic lipidosis is a common pathological finding in the American mink (Neovison vison) and can be caused by nutritional imbalance due to obesity or rapid body weight loss. The objectives of the present study
were to investigate the timeline and characterize the development of hepatic lipidosis in mink in response to 0–7 days of
food deprivation and liver recovery after 28 days of re-feeding. We report here the effects on hematological and endocrine
variables, body fat mobilization, the development of hepatic lipidosis and the alterations in the liver lipid classes and
tissue fatty acid (FA) sums. Food deprivation resulted in the rapid mobilization of body fat, most notably visceral, causing
elevated hepatosomatic index and increased liver triacylglycerol content. The increased absolute amounts of liver total phospholipids
and phosphatidylcholine suggested endoplasmic reticulum stress. The hepatic lipid infiltration and the altered liver lipid
profiles were associated with a significantly reduced proportion of n-3 polyunsaturated FA (PUFA) in the livers and the decrease
was more evident in the females. Likewise, re-feeding of the female mink resulted in a more pronounced recovery of the liver
n-3 PUFA. The rapid decrease in the n-3/n-6 PUFA ratio in response to food deprivation could trigger an inflammatory response
in the liver. This could be a key contributor to the pathophysiology of fatty liver disease in mink influencing disease progression. 相似文献
63.
Ursula Wölwer-Rieck und Hans Büning-Pfaue 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1990,191(4-5):319-321
Zusammenfassung Es wird eine HPLC-Methode vorgestellt, die es gestattet, Furazolidon (FZ) neben seinem offenkettigen Cyanometaboliten 3-(4-Cyano-2-oxobutyli-denamino)-2-oxazolidon (M1) in Forellen nachzuweisen. Im Muskel und Leber von Forellen, die 7 Tage lang mit FZ-haltigem Futter behandelt worden waren, konnten nur während der Behandlungszeit Rückstände von M1 und FZ nachgewiesen werden. Schon zu Beginn der Absetzzeit lagen die Konzentrationen an FZ und M1 unterhalb der Nachweisgrenze.
The residue behaviour of the furazolidone metabolite 3-(4-Cyano-2-oxobutylideneamino)-2-oxazolidone in trout
Summary A high-performance liquid chromatography (HPLC)-method for the determination of furazolidone (FZ) and its open-chain cyano-derivative 3-(4-cyano-2-oxobutylideneamino)-2-oxazolidone (M1) in trout is described. Only during the medication period residues of FZ and M1 were detected in the muscle and liver of the trout, which were treated with food containing FZ over a period of 7 days. After the beginning of the withdrawal period, the concentration of FZ and M1 were found to be under the limits of detection.相似文献
64.
Celeste Fernández Eduardo Lujano Ursula Macias Josseilin Marcano Pablo J. Baricelli Clementina Longo Sergio A. Moya María G. Solórzano Marisol C. Ortega Alvaro J. Pardey 《Catalysis Letters》2004,95(3-4):143-150
Rhodium(I) complexes of the type, cis-[Rh(CO)2(amine)2](PF6) where (amine = 3-picoline, 2-picoline, pyridine, 2,6-lutidina or 3,5-lutidine) dissolved in 80% aqueous amine solutions catalyzed the selective reduction of 4-nitrobenzoic acid to 4-aminobenzoic acid under CO atmosphere. The importance of these catalytic systems is their high chemo selectivity for the aromatic nitro group of the 4-nitrobenzoic acid with respect to the carboxylic group, allowing the production of the desired aromatic amine in high yields. The 4-aminobenzoic acid production depends on the nature of the coordinated amine. The Rh/3,5-lutidine system, the most active catalyst among tested, displays turnover frequencies for 4-aminobenzoic acid production of about 173 moles per mole Rh per day for [Rh] = 1 × 10?4 mol, [4-nitrobenzoic acid] = 3.82 × 10?3mol, 10 mL of 80% aqueous 3,5-lutidine, P(CO) = 0.9 atm at 100 °C. Analyses of kinetic results for the Rh/3,5-lutidine system show a first order dependence on 4-nitrobenzoic acid concentration, a non-linear dependence on CO pressure, a segmented Arrhenius plot and dependence on the nature of the reducing gas agent. These data are discussed in terms of a possible mechanism. 相似文献
65.
The adsorption and reaction of toluene on vanadyl pyrophosphate catalysts was studied by in situ infrared spectroscopy. Strongly
adsorbed benzaldehyde and physically adsorbed cyclic anhydride species were observed at temperatures above 523 K. Water formed
during reaction generates acid hydroxyl groups which cause a stronger adsorption of benzaldehyde and consecutive oxidation
reactions. By co-adsorption of pyridine the acid sites are blocked and the deeper oxidation is suppressed.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
66.
67.
Baltes Paul B.; Staudinger Ursula M.; Maercker Andreas; Smith Jacqui 《Canadian Metallurgical Quarterly》1995,10(2):155
This study examined whether our conception of wisdom has a psychological bias, by focusing on a group of distinguished individuals nominated as being wise. The comparison groups included older clinical psychologists and highly educated old and young control groups. Wisdom-related knowledge was assessed by 2 tasks and evaluated with a set of 5 wisdom criteria. First, old wisdom nominees performed as well as clinical psychologists who in past research had shown the highest levels of performance. Second, wisdom nominees excelled in the task of existential life management and the criterion of value relativism. Third, up to age 80, older adults performed as well as younger adults. If there is a psychological bias to our conception of wisdom, this does not prevent nonpsychologists from being among the top performers. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
68.
Matthias C. Schulz Paula Korn Bernd Stadlinger Ursula Range Stephanie Möller Jana Becher Matthias Schnabelrauch Ronald Mai Dieter Scharnweber Uwe Eckelt Vera Hintze 《Journal of materials science. Materials in medicine》2014,25(1):247-258
Dental implants are an established therapy for oral rehabilitation. High success rates are achieved in healthy bone, however, these rates decrease in compromised host bone. Coating of dental implants with components of the extracellular matrix is a promising approach to enhance osseointegration in compromised peri-implant bone. Dental titanium implants were coated with an artificial extracellular matrix (aECM) consisting of collagen type I and either one of two regioselectively low sulfated hyaluronan (sHA) derivatives (coll/sHA1Δ6s and coll/sHA1) and compared to commercial pure titanium implants (control). After extraction of the premolar teeth, 36 implants were inserted into the maxilla of 6 miniature pigs (6 implants per maxilla). The healing periods were 4 and 8 weeks, respectively. After animal sacrifice, the samples were evaluated histomorphologically and histomorphometrically. All surface states led to a sufficient implant osseointegration after 4 and 8 weeks. Inflammatory or foreign body reactions could not be observed. After 4 weeks of healing, implants coated with coll/sHA1Δ6s showed the highest bone implant contact (BIC; coll/sHA1Δ6s: 45.4 %; coll/sHA1: 42.2 %; control: 42.3 %). After 8 weeks, a decrease of BIC could be observed for coll/sHA1Δ6s and controls (coll/sHA1Δ6s: 37.3 %; control: 31.7 %). For implants coated with coll/sHA1, the bone implant contact increased (coll/sHA1: 50.8 %). Statistically significant differences could not be observed. Within the limits of the current study, aECM coatings containing low sHA increase peri-implant bone formation around dental implants in maxillary bone compared to controls in the early healing period. 相似文献
69.
Iqbal U Albaghdadi H Nieh MP Tuor UI Mester Z Stanimirovic D Katsaras J Abulrob A 《Nanotechnology》2011,22(19):195102
Molecular imaging enables the non-invasive investigation of cellular and molecular processes. Although there are challenges to overcome, the development of targeted contrast agents to increase the sensitivity of molecular imaging techniques is essential for their clinical translation. In this study, spontaneously forming, small unilamellar vesicles (sULVs) (30 nm diameter) were used as a platform to build a bimodal (i.e., optical and magnetic resonance imaging (MRI)) targeted contrast agent for the molecular imaging of brain tumors. sULVs were loaded with a gadolinium (Gd) chelated lipid (Gd-DPTA-BOA), functionalized with targeting antibodies (anti-EGFR monoclonal and anti-IGFBP7 single domain), and incorporated a near infrared dye (Cy5.5). The resultant sULVs were characterized in vitro using small angle neutron scattering (SANS), phantom MRI and dynamic light scattering (DLS). Antibody targeted and nontargeted Gd loaded sULVs labeled with Cy5.5 were assessed in vivo in a brain tumor model in mice using time domain optical imaging and MRI. The results demonstrated that a spontaneously forming, nanosized ULVs loaded with a high payload of Gd can selectively target and image, using MR and optical imaging, brain tumor vessels when functionalized with anti-IGFBP7 single domain antibodies. The unique features of these targeted sULVs make them promising molecular MRI contrast agents. 相似文献
70.
Reducing the startup time of aerobic granular sludge reactors through seeding floccular sludge with crushed aerobic granules 总被引:1,自引:0,他引:1
One of the main challenging issues for the aerobic granular sludge technology is the long startup time when dealing with real wastewaters. This study presents a novel strategy to reduce the time required for granulation while ensuring a high level of nutrient removal. This new approach consists of seeding the reactor with a mixture of crushed aerobic granules and floccular sludge. The effectiveness of the strategy was demonstrated using abattoir wastewater, containing nitrogen and phosphorus at approximately 250 mgN/L and 30 mgP/L, respectively. Seven different mixtures of crushed granules and floccular sludge at granular sludge fractions (w/w in dry mass) of 0%, 5%, 10%, 15%, 25%, 30% and 50% were used to start eight granulation processes. The granulation time (defined as the time when the 10th percentile bacterial aggregate size is larger than 200 μm) displayed a strong dependency on the fraction of granular sludge. The shortest granulation time of 18 days was obtained with 50% crushed granules, in comparison with 133 days with 5% crushed granules. Full granulation was not achieved in the two trials without seeding with crushed granules. In contrast to the 100% floccular sludge cases, where a substantial loss of biomass occurred during granulation, the biomass concentration in all other trails did not decrease during granulation. This allowed that good nitrogen removal was maintained in all the reactors during the granulation process. However, enhanced biological phosphorus removal was achieved in only one of the eight trials. This was likely due to the temporary accumulation of nitrite, a strong inhibitor of polyphosphate accumulating organisms. 相似文献