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121.
Kerrie Unsworth Elisa AdriasolaAmber Johnston-Billings Alina DmitrievaMelinda Hodkiewicz 《Reliability Engineering & System Safety》2011,96(11):1474-1481
Many have recognized the need for high quality data on assets and the problems in obtaining them, particularly when there is a need for human observation and manual recording. Yet very few have looked at the role of the data collectors themselves in the data quality process. This paper argues that there are benefits to more fully understanding the psychological factors that lay behind data collection and we use goal hierarchy theory to understand these factors. Given the myriad of potential reasons for poor-quality data it has previously proven difficult to identify and successfully deploy employee-driven interventions; however, the goal hierarchy approach looks at all of the goals that an individual has in their life and the connections between them. For instance, does collecting data relate to whether or not they get a promotion? Stay safe? Get a new job? and so on. By eliciting these goals and their connections we can identify commonalities across different groups, sites or organizations that can influence the quality of data collection. Thus, rather than assuming what the data collectors want, a goal hierarchy approach determines that empirically. Practically, this supports the development of customized interventions that will be much more effective and sustainable than previous efforts. 相似文献
122.
Exfoliated graphitic nanoplatelets (xGnPs) show adsorption capability and adsorption efficiency for lead removal from water, the adsorption being influenced by the solution pH value and the xGnPs surface characteristics, which are controlled by their treatment processing. The adsorption isotherms were described by both Langmuir and Freundlich models. These results suggest that xGnPs are remarkable lead adsorbents, having potential applications in environmental protection. 相似文献
123.
124.
Dr. Camelia Vlad Kathrin Lindner Dr. Christiaan Karreman Dr. Stefan Schildknecht Prof. Marcel Leist Nick Tomczyk Dr. John Rontree Dr. James Langridge Dr. Karin Danzer Dr. Thomas Ciossek Dr. Alina Petre Prof. Dr. Michael L. Gross Prof. Dr. Bastian Hengerer Prof. Dr. Michael Przybylski 《Chembiochem : a European journal of chemical biology》2011,12(18):2706-2706
125.
Monica Daescu Miruna Iota Constantin Serbschi Alina C. Ion Mihaela Baibarac 《International journal of molecular sciences》2021,22(8)
Photodegradation of the aqueous solutions of acetylsalicylic acid, in the absence (ASA) and the presence of excipients (ASE), is demonstrated by the photoluminescence (PL). A shift of the PL bands from 342 and 338 nm to 358 and 361–397 nm for ASA and ASE in solid state and as aqueous solutions was reported. By exposure of the solution of ASA 0.3 M to UV light, a decrease in the PL band intensity was highlighted. This behavior was revealed for ASA in the presence of phosphate buffer (PB) having the pH equal to 6.4, 7, and 8 or by the interaction with NaOH 0.3 M. A different behavior was reported in the case of ASE. In the presence of PB, an increase in the intensity of the PL band of ASE simultaneously with a change of the ratio between the intensities of the bands at 361–364 and 394–397 nm was highlighted. The differences between PL spectra of ASA and ASE have their origin in the presence of salicylic acid (SAL). The interaction of ASE with NaOH induces a shift of the PL band at 405–407 nm. Arguments for the reaction of ASA with NaOH are shown by Raman scattering and FTIR spectroscopy. 相似文献
126.
127.
Aleksandra Wajda Wolfgang H. Goldmann Rainer Detsch Alina Grünewald Aldo R. Boccaccini Maciej Sitarz 《Ceramics International》2018,44(18):22698-22709
Gallium-containing glasses were synthesized by the sol-gel and traditional melting techniques to obtain bioactive amorphous materials with antibacterial and angiogenic properties. The influence of gallium ion addition on glass structure was described using two spectroscopic methods (FTIR and 29Si MAS NMR). DSC (Differential Scanning Calorimetry) analysis revealed differences in thermal properties, which were explained by varying ionicity of the chemical bonds. The study shows that gallium ions addition causes a significant difference in glass structure and, as a consequence, in thermal properties, microstructure, and biological response. Dissolution products of the researched glasses incubated in SBF and distillated water were analyzed by inductively coupled plasma mass spectrometry (ICP-MS). To perform the indirect in vitro biocompatibility studies, human osteoblast-like cells (MG-63) were cultivated in the supernatants, which were obtained by incubation of the glass powders in the cell culture medium. The evaluation of the potential angiogenic properties of gallium-doped glasses was performed by measuring the release of human vascular endothelial growth factor (VEGF) from MG-63 cells. Dissolution products of the all samples were tested for antibacterial activity against gram-negative (E. coli) and gram-positive bacteria (S. aureus). 相似文献
128.
129.
Simone Krueger Alexander Riess Anika Jonitz-Heincke Alina Weizel Anika Seyfarth Hermann Seitz Rainer Bader 《International journal of molecular sciences》2021,22(1)
In cell-based therapies for cartilage lesions, the main problem is still the formation of fibrous cartilage, caused by underlying de-differentiation processes ex vivo. Biophysical stimulation is a promising approach to optimize cell-based procedures and to adapt them more closely to physiological conditions. The occurrence of mechano-electrical transduction phenomena within cartilage tissue is physiological and based on streaming and diffusion potentials. The application of exogenous electric fields can be used to mimic endogenous fields and, thus, support the differentiation of chondrocytes in vitro. For this purpose, we have developed a new device for electrical stimulation of chondrocytes, which operates on the basis of capacitive coupling of alternating electric fields. The reusable and sterilizable stimulation device allows the simultaneous use of 12 cavities with independently applicable fields using only one main supply. The first parameter settings for the stimulation of human non-degenerative chondrocytes, seeded on collagen type I elastin-based scaffolds, were derived from numerical electric field simulations. Our first results suggest that applied alternating electric fields induce chondrogenic re-differentiation at the gene and especially at the protein level of human de-differentiated chondrocytes in a frequency-dependent manner. In future studies, further parameter optimizations will be performed to improve the differentiation capacity of human cartilage cells. 相似文献
130.
Dan Florin Anghel Shuji Saito Alina Iovescu Adriana Băran Gabriela Stîngă 《Journal of surfactants and detergents》2011,14(1):91-101
This work investigates decylammonium salts, with inorganic (chloride and thiocyanate) and organic (acetate and butyrate) counterions,
in interaction with poly(methacrylic acid) (PMA). The study is conducted by means of surface tension, relative viscosity and
pH measurements. The role of the methyl group in PMA appears by comparison with analogous mixtures of poly(acrylic acid) (PAA).
In aqueous solution, a non-cooperative interaction between the surfactant and the hydrophobic microdomains (HMD) of PMA starts
first. With surfactant addition, micellar aggregates bound onto the polymer chain appear at a concentration T
1, which is higher than for the analogous PAA systems, but lower than the respective CMC. T
1 is lower for chloride than for thiocyanate and lower for acetate than for butyrate. Depending on the counterion, the HMD
conceal or expose carboxyl groups, with influence upon the interaction strength and the bulk and surface behavior. Stronger
interactions and maxima of surface tension and relative viscosity appear for the systems with organic counterions. An estimation
of the interaction strength shows weaker surfactant interactions with PMA than with PAA, and that acetate induces the strongest
interaction while thiocyanate the weakest. 相似文献