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91.
Novel families of flexible, semiflexible and rigid crosslinked polyesters were prepared from modified natural oils such as soybean, rape-seed and linseed oil. Maleinated oils were used as anhydride-functional curing agents of epoxy resins such as bisphenol-A-diglycidylether and epoxidized natural oils. A new class of unsaturated polyester resins was based upon maleic anhydride, epoxidized natural oils and styrene. The resulting thermosetting polyesters were reinforced with natural fibers such as hemp and flax fibers. The influence of molecular architectures, curing conditions and formulations on thermal, mechanical and morphological properties were investigated. 相似文献
92.
This study is to examine the effect of robots’ language forms on people’s acceptance of robots. We applied a concept of social distance to measure people’s acceptance of robots. In an experiment, calling participants by name vs. not calling by name as well as the robot’s speech styles (familiar vs. honorific), were used to impose a verticality and horizontality of social relationships between participants and robots. After the conversation with a robot, participants rated the robot’s interpersonal traits and their comfortable approach distance to the robot, and their response to the robot during the experiment were analyzed. As a result, participants whom the robot called by their name perceived the robot as friendlier. They introduced themselves more actively, and were more intently focused on what the robot said. They asked the robot questions more frequently. Participants called by their names consequently approached the robot more closely than participants who were not called. An interaction effect was found between speech styles and whether names were used in regard to the perceived friendliness of robots, negative response to robots, and comfortable approach distance to robots. We discuss verbal interaction design for increasing people’s acceptance of robots. 相似文献
93.
Isabel C. Cohen Emry R. Cohenour Kristen G. Harnett Sonya M. Schuh 《International journal of molecular sciences》2021,22(10)
Bisphenol A (BPA) is an endocrine-disrupting chemical used in the production of plastics, and is linked to developmental, reproductive, and metabolic disorders including obesity. Manufacturers have begun using ‘BPA-free’ alternatives instead of BPA in many consumer products. However, these alternatives have had much less testing and oversight, yet they are already being mass-produced and used across industries from plastics to food-contact coatings. Here, we used human female adipose-derived stem cells (hASCs), a type of adult mesenchymal stem cell, to compare the effects of BPA and BPA alternatives on adipogenesis or fat cell development in vitro. We focused on two commonly used BPA replacements, bisphenol AF (BPAF) and tetramethyl bisphenol F (TMBPF; monomer of the new valPure V70 food-contact coating). Human ASCs were differentiated into adipocytes using chemically defined media in the presence of control differentiation media with and without 17β-estradiol (E2; 10 μM), or with increasing doses of BPA (0, 0.1 and 1 μM), BPAF (0, 0.1, 1 and 10 nM), or TMBPF (0, 0.01 and 0.1 μM). After differentiation, the cells were stained and imaged to visualize and quantify the accumulation of lipid vacuoles and number of developing fat cells. Treated cells were also examined for cell viability and apoptosis (programmed cell death) using the respective cellular assays. Similar to E2, BPA at 0.1 μM and BPAF at 0.1 nM, significantly increased adipogenesis and lipid production by 20% compared to control differentiated cells (based on total lipid vacuole number to cell number ratios), whereas higher levels of BPA and BPAF significantly decreased adipogenesis (p < 0.005). All tested doses of TMBPF significantly reduced adipogenesis and lipid production by 30–40%, likely at least partially through toxic effects on stem cells, as viable cell numbers decreased and apoptosis levels increased throughout differentiation. These findings indicate that low, environmentally-relevant doses of BPA, BPAF, and TMBPF have significant effects on fat cell development and lipid accumulation, with TMBPF having non-estrogenic, anti-adipogenic effects. These and other recent results may provide a potential cellular mechanism between exposure to bisphenols and human obesity, and underscore the likely impact of these chemicals on fat development in vivo. 相似文献
94.
Nock Matthew K.; Prinstein Mitchell J.; Sterba Sonya K. 《Canadian Metallurgical Quarterly》2009,118(4):816
Self-injurious behaviors are among the leading causes of death worldwide. However, the basic nature of self-injurious thoughts and behaviors (SITBs) is not well understood because prior studies have relied on long-term, retrospective, aggregate, self-report assessment methods. The authors used ecological momentary assessment methods to measure suicidal and nonsuicidal SITBs as they naturally occur in real time. Participants were 30 adolescents and young adults with a recent history of self-injury who completed signal- and event-contingent assessments on handheld computers over a 14-day period, resulting in the collection of data on 1,262 thought and behavior episodes. Participants reported an average of 5.0 thoughts of nonsuicidal self-injury (NSSI) per week, most often of moderate intensity and short duration (1–30 min), and 1.6 episodes of NSSI per week. Suicidal thoughts occurred less frequently (1.1 per week), were of longer duration, and led to self-injurious behavior (i.e., suicide attempts) less often. Details are reported about the contexts in which SITBs most often occur (e.g., what participants were doing, who they were with, and what they were feeling before and after each episode). This study provides a first glimpse of how SITBs are experienced in everyday life and has significant implications for scientific and clinical work on self-injurious behaviors. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
95.
Compas Bruce E.; Forehand Rex; Keller Gary; Champion Jennifer E.; Rakow Aaron; Reeslund Kristen L.; McKee Laura; Fear Jessica M.; Colletti Christina J. M.; Hardcastle Emily; Merchant Mary Jane; Roberts Lori; Potts Jennifer; Garai Emily; Coffelt Nicole; Roland Erin; Sterba Sonya K.; Cole David A. 《Canadian Metallurgical Quarterly》2009,77(6):1007
A family cognitive-behavioral preventive intervention for parents with a history of depression and their 9–15-year-old children was compared with a self-study written information condition in a randomized clinical trial (n = 111 families). Outcomes were assessed at postintervention (2 months), after completion of 4 monthly booster sessions (6 months), and at 12-month follow-up. Children were assessed by child reports on depressive symptoms, internalizing problems, and externalizing problems; by parent reports on internalizing and externalizing problems; and by child and parent reports on a standardized diagnostic interview. Parent depressive symptoms and parent episodes of major depression also were assessed. Evidence emerged for significant differences favoring the family group intervention on both child and parent outcomes; strongest effects for child outcomes were found at the 12-month assessment with medium effect sizes on most measures. Implications for the prevention of adverse outcomes in children of depressed parents are highlighted. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
96.
Dal Cin Sonya; Worth Keilah A.; Gerrard Meg; Gibbons Frederick X.; Stoolmiller Mike; Wills Thomas A.; Sargent James D. 《Canadian Metallurgical Quarterly》2009,28(4):473
Objective: To investigate the psychological processes that underlie the relation between exposure to alcohol use in media and adolescent alcohol use. Design: The design consisted of a structural equation modeling analysis of data from four waves of a longitudinal, nationally representative, random-digit dial telephone survey of adolescents in the United States. Main Outcome Measures: The main outcome measures were adolescent alcohol consumption and willingness to use alcohol. Tested mediators were alcohol-related norms, prototypes, expectancies, and friends’ use. Results: Alcohol prototypes, expectancies, willingness, and friends’ use of alcohol (but not perceived prevalence of alcohol use among peers) were significant mediators of the relation between movie alcohol exposure and alcohol consumption, even after controlling for demographic, child, and family factors associated with both movie exposure and alcohol consumption. Conclusion: Established psychological and interpersonal predictors of alcohol use mediate the effects of exposure to alcohol use in movies on adolescent alcohol consumption. The findings suggest that exposure to movie portrayals may operate through similar processes as other social influences, highlighting the importance of considering these exposures in research on adolescent risk behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
97.
Gibbons Frederick X.; Pomery Elizabeth A.; Gerrard Meg; Sargent James D.; Weng Chih-Yuan; Wills Thomas A.; Kingsbury John; Dal Cin Sonya; Worth Keilah A.; Stoolmiller Mike; Tanski Susanne E.; Yeh Hsiu-Chen 《Canadian Metallurgical Quarterly》2010,24(4):649
Racial differences in the effects of peer and media influence on adolescents' alcohol cognitions and consumption were examined in a large-scale panel study. With regard to peer influence, results from cross-lagged panel analyses indicated that the relation between perceived peer drinking and own drinking was significant for both Black and White adolescents, but it was stronger for the White adolescents. With regard to media influence, structural modeling analyses indicated that exposure to drinking in movies was associated with more alcohol consumption 8 months and 16 months later. These effects were mediated by increases in the favorability of the adolescents' drinker prototypes, their willingness to drink, and their tendency to affiliate with friends who were drinking. Multiple group analyses indicated that, once again, the effects (both direct and indirect) were much stronger for White adolescents than for Black adolescents. The results suggest media influence works in a similar manner to social influence and that Whites may be more susceptible to both types of influence. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
98.
Grace Welsh Kate Ryder Jodi Brewster Christina Walker Sonya Mros Alaa El‐Din A. Bekhit Michelle McConnell Alan Carne 《International Journal of Food Science & Technology》2017,52(5):1252-1259
Novel bacterial (HT) and fungal (FPII) food‐grade protease preparations were evaluated for their ability to hydrolyse sheep cheese whey (SCW) and the generation of bioactive peptides. Both protease preparations hydrolysed the whey proteins to small peptides over 24‐h hydrolysis time, but the time course hydrolysis profiles were different as evaluated by SDS‐PAGE. The HT whey hydrolysate had considerably higher antioxidant and angiotensin‐I converting enzyme (ACE)‐inhibitor activity than the FPII hydrolysate. Neither hydrolysate was cytotoxic towards Vero cells. OFFGEL electrophoresis of the small peptide pool fraction (<15 amino acids) of each hydrolysate indicated differences in the pI distribution of the bioactive peptides. This likely reflects the diverse hydrolytic specificity of the proteases. Although the antioxidant activity of both hydrolysates was not significantly affected by simulated gastrointestinal digestion, the loss of ACE‐inhibitor activity was greater with the FPII hydrolysate. 相似文献
99.
100.
Sol-gel-derived SnO2 and Fe2O3 were selectively deposited on elements of micro hot plate (microHP) arrays. The silicon micromachined microHP arrays contain heating elements (100 microm x 100 microm) that are electronically addressable and thermally isolated from each other. Thin films of (tridecafluoro-1,1,2,2-tetrahydrooctyl)trichlorosilane (TFS) or hexyltrichlorosilane (HFS) assembled on surfaces of the arrays served as thermally sensitive resists whereby heating of specific microHPs resulted in removal of organosilane films only in heated areas. TFS-masked surfaces were characterized with condensation figures and secondary ion mass spectrometry (SIMS) imaging. TFS was removed from regions heated above 400 degrees C to expose hydrophilic surfaces, while TFS films in unheated areas were unaffected and remained hydrophobic. Sol-gel tin oxide spin-coated on the thermally patterned arrays adhered only to the hydrophilic regions and was repelled from the hydrophobic areas masked by the TFS films. By using HFS films, it was possible to selectively deposit two sol-gel materials, SnO2 and Fe2O3, on different microHPs in the same array as confirmed by SIMS imaging. Both materials showed varying degrees of electrical response to hydrogen and methanol in gas-sensing measurements. 相似文献