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91.
Alisa Schnellbaecher Anton Lindig Maxime Le Mignon Tim Hofmann Brit Pardon Stephanie Bellmaine Aline Zimmer 《International journal of molecular sciences》2021,22(12)
Biomanufacturing processes may be optimized by storing cell culture media at room temperature, but this is currently limited by their instability and change in color upon long-term storage. This study demonstrates that one of the critical contributing factors toward media browning is tryptophan. LC-MS technology was utilized to identify tryptophan degradation products, which are likely formed primarily from oxidation reactions. Several of the identified compounds were shown to contribute significantly to color in solutions but also to exhibit toxicity against CHO cells. A cell-culture-compatible antioxidant, a-ketoglutaric acid, was found to be an efficient cell culture media additive for stabilizing components against degradation, inhibiting the browning of media formulations, and decreasing ammonia production, thus providing a viable method for developing room-temperature stable cell culture media. 相似文献
92.
Structure,Protein Interactions and In Vitro Protease Accessibility of Extruded and Pressurized Full-Fat Soybean Flakes 总被引:3,自引:1,他引:2
Stephanie Jung Abdullah Mahfuz Devin Maurer 《Journal of the American Oil Chemists' Society》2009,86(5):475-483
The objectives of the present study were to determine how extrusion (barrel temperature of 100 °C) and high-pressure processing
(HPP, 200 and 500 MPa, 15 min, 25 °C) of full-fat soybean flakes (FFSF) modified the structure of soybean cotyledon cells,
the protein interactions and the in vitro protease accessibility. Cellular disruption of the cotyledon cells was only observed
for extruded FFSF. Extrusion and HPP at 500 MPa favored formation of insoluble protein aggregates, in which oil was entrapped.
High pressure size exclusion chromatography (HPSEC) and extraction methods using buffers containing SDS and 2-mercaptoethanol
suggested that noncovalent interactions were the main forces in protein aggregate formation during HPP 500 MPa and extrusion.
Intermolecular cross-linking by disulfide bonding was also involved in insoluble aggregates, but at a lesser extent than noncovalent
interactions. Extrusion and HPP 500-MPa treatment enhanced the proteolytic attack, while treatment at 200 MPa had no impact.
Drastic changes in the peptide profile of the extracted proteins were, however, only observed for the enzyme-treated 500-MPa
FFSF. Optimal oil and protein extraction yields required cellular disruption of cotyledon cells and hydrolysis of protein
aggregates, which were obtained with enzyme-assisted aqueous extraction of extruded FFSF. 相似文献
93.
We examined whether personality judgments were present in texts of the diverse religious and philosophical traditions that emerged during the Great Transformation, an era spanning roughly 1000 BCE to 200 BCE. Some psychologists have suggested that the tendency of humans to judge personality has evolved; if some ancient societies failed to record personality judgments, it would be evidence against such an evolutionary position. In addition, learning about the prevalence and specifics of ancient personality judgments can help psychologists better understand the prehistory of personality psychology. Eight cultural traditions were studied: two each from China (Confucianism, Taoism), Greece (Classical and Hellenistic philosophy), India (Buddhism, Hinduism), and the Middle East (Judaism, Zoroastrianism). We found evidence that personality judgments were an important aspect of all of these traditions. Not only did people judge one another, but they also offered instructions on how to judge others. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
94.
95.
Stephanie Lansing Jay F. Martin Raúl Botero Botero Tatiana Nogueira da Silva Ederson Dias da Silva 《Biomass & bioenergy》2010,34(12):1711-1720
A nine-month co-digestion investigation was conducted in Costa Rica to optimize animal wastewater treatment, renewable energy production, and fertilizer creation using 12 Taiwanese-model, plug-flow digesters (250 L each) constructed of tubular polyethylene and PVC piping, operating without mechanical or heating components. The experiment tested three replications of four treatment groups: the control (T0), which contained only swine manure, and T2.5, T5, and T10, which contained 2.5%, 5%, and 10% used cooking grease (by volume) combined with swine manure.T2.5 had the greatest methane production (45 L d?1), a 124% increase from the control. No adverse effects were observed from co-digesting 2.5% grease in terms of organic matter removal, pathogen reduction, grease removal, and pH. Chemical oxygen demand (COD) was reduced 94.7% to 1.96 g L?1, fecal coliforms and Escherichia coli were reduced 99.2 and 97.1%, respectively, and grease removal was 99.9%. The average effluent pH (7.05) and alkalinity in T2.5 was within the optimal range for methanogens and increased significantly during the nine-month experiment, likely due to adaptation of the methanogenic organisms to the influent grease concentrations. Total nitrogen concentration decreased 34.0%, and NH4-N increased 97.1% during digestion in T2.5, with no significant differences between T2.5 and T0. There was less phosphorus reduction with co-digestion, with 181 mg g?1 of total phosphorus (TP) in T2.5 and only 90.6 mg g?1 of TP in T0, resulting in lower N:P ratios in the grease treatment groups due to the greater concentration of phosphorus in the effluent. 相似文献
96.
Stephanie G. Adams 《工程教育杂志》2001,90(4):597-600
Within the last decade, teamwork has become a well‐known phenomenon in U.S. industry. Effective teamwork has led to an increase in productivity, a reduction in costs, a rise in employee involvement, and flattening of the organizational structure.1 This study examines students' attitudes and experiences towards working in teams, with particular attention paid to engineering students participating in entrepreneurial teams. The results of the study suggest that the students' attitudes and experiences were positive about working in teams. The majority of the students felt they were able to perform effectively in teams and thought that working in teams will be beneficial for preparing them for the workplace. Although students responded positively about their teamwork experience, only half of the students received team training. Some of the students felt indifferent about the usefulness of the team training sessions, which suggests that teamwork training needs to be improved. 相似文献
97.
Christ Mary Anne G.; Lahey Benjamin B.; Frick Paul J.; Russo Mary F.; McBurnett Keith; Loeber Rolf; Stouthamer-Loeber Magda; Green Stephanie 《Canadian Metallurgical Quarterly》1990,58(6):840
Early motherhood (r?=?.33) with the number of Diagnostic and Statistical Manual of Mental Disorders (DSM-III) symptoms of conduct disorder in a sample of 253 boys (aged 6–13 yrs) who had been referred to outpatient clinics. The following models were compared using path analysis: (1) Teenage motherhood, parental antisocial personality, and socioeconomic status (SES) each contribute uniquely to the prediction of childhood conduct problems; (2) teenage motherhood mediates the association of SES and parental antisocial personality with child conduct problems; and (3) teenage motherhood is spuriously related with child conduct problems because of common associations with SES and parental antisocial personality. Model (3) best fit the data. Similar results were obtained whether maternal age at the birth of the firstborn child or the proband child was used to define maternal age and when teenage motherhood was defined as giving birth at 相似文献
98.
Gordon Rugg Malcolm Eva Atiya Mahmood Nazia Rehman Stephanie Andrews & Sarah Davies 《Information Systems Journal》2002,12(3):215-229
Abstract. Eliciting information about organizational culture is an important part of system analysis and design. However, eliciting knowledge of this sort is difficult. Laddering is an established technique that is particularly suitable for eliciting information about goals and for eliciting explanations, which are important issues when investigating organizational culture. This paper describes the method, its strengths and limitations, its use in several case studies and its relation to other elicitation techniques. Recommendations for further work are given. 相似文献
99.
Weary Gifford; Jacobson Jill A.; Edwards John A.; Tobin Stephanie J. 《Canadian Metallurgical Quarterly》2001,81(2):206
In 3 studies, we examined the hypothesis that the effects of stereotype usage on target judgments are moderated by causal uncertainty beliefs and related accuracy goal structures. In Study 1, we focused on the role of chronically accessible causal uncertainty beliefs as predictors of a target's level of guilt for an alleged academic misconduct offense. In Study 2, we examined the role of chronic causal uncertainty reduction goals and a manipulated accuracy goal; in Study 3, we investigated the role of primed causal uncertainty beliefs on guilt judgments. In all 3 studies, we found that activation of causal uncertainty beliefs and accuracy concerns was related to a reduced usage of stereotypes. Moreover, this reduction was not associated with participants' levels of perceived control, depression, state affect, need for cognition, or personal need for structure. Results are discussed in terms of their implications for the model of causal uncertainty and, more generally, in terms of the motivational processes underlying stereotype usage. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
100.
Emmett P. O'Brien Stephanie Goldfarb Christopher C. White 《The Journal of Adhesion》2005,81(6):599-621
In the shaft-loaded blister test (SLBT), plastic deformation often occurs at the contact area between the shaft tip and adhesive layer, leading to a larger displacement (blister height) than if the film was loaded elastically. As a consequence, incorporating the displacement variable into the analysis can result in misleading values of the applied strain energy-release rate, G. In this work, the influence of plastic yielding at the contact area on G of a thin film was investigated as a function of some common SLBT experimental variables, namely, substrate hole diameter, film thickness, and shaft-tip diameter. Test specimens consisted of plies of pressure-sensitive adhesive tape adhered to a rigid glass substrate. G was calculated from the following Equations: (1) load-based, (2) hybrid, (3) displacement-based, and (4) combination. Decreasing the film thickness, increasing the hole diameter, or decreasing the shaft-tip diameter lead to more plastic yielding at the contact area as well as to an increase in blister height. The increased blister height resulting from plastic deformation leads to disagreement among the values of G calculated from the different Equations when the displacement variable was included in the calculation. However, the load-based equation, which does not include the displacement, was determined to be independent of plastic yielding and the “correct” equation for calculating G. In addition, the film tensile rigidity (Eh) was calculated using an experimental compliance calibration. The effects of film thickness on the mechanical behavior of the film (bending plate vs. stretching membrane) as well as methods to determine the displacement resulting from plastic deformation are also discussed. 相似文献