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71.
This work investigates social curating activities on the website Pinterest and relates them to the librarian's traditional role of curating information. Pinterest is a social curation site that combines features of gathering, creating, and sharing with the information management characteristics of successful data curation. Libraries have begun to think about pushing services into social networking sites and adding social networking features to their own services. This study evaluates the webpages of Association of Research Libraries member libraries for presence and use of Pinterest, and suggests ways research and academic libraries can use Pinterest to support their patrons. 相似文献
72.
73.
This perspective will highlight the significant advances in the field of fluorinated organically modified silicas occurring since 2014. After a brief introduction, an overview of the synthetic methods employed for obtaining these organic–inorganic hybrid materials with an emphasis on the lesser utilized and new synthetic methods will be given. Furthermore, novel applications beyond the more traditional non‐wetting coatings and surfaces will also be featured. © 2015 Society of Chemical Industry 相似文献
74.
Yei-Tsung Chen Juan Wang Abby S. Y. Wee Quek-Wei Yong Edgar Lik-Wui Tay Chin Cheng Woo Vitaly Sorokin Arthur Mark Richards Lieng-Hsi Ling 《International journal of molecular sciences》2016,17(5)
Myxomatous mitral valve prolapse (MMVP) and fibroelastic deficiency (FED) are two common variants of degenerative mitral valve disease (DMVD), which is a leading cause of mitral regurgitation worldwide. While pathohistological studies have revealed differences in extracellular matrix content in MMVP and FED, the molecular mechanisms underlying these two disease entities remain to be elucidated. By using surgically removed valvular specimens from MMVP and FED patients that were categorized on the basis of echocardiographic, clinical and operative findings, a cluster of microRNAs that expressed differentially were identified. The expressions of has-miR-500, -3174, -17, -1193, -646, -1273e, -4298, -203, -505, and -939 showed significant differences between MMVP and FED after applying Bonferroni correction (p < 0.002174). The possible involvement of microRNAs in the pathogenesis of DMVD were further suggested by the presences of in silico predicted target sites on a number of genes reported to be involved in extracellular matrix homeostasis and marker genes for cellular composition of mitral valves, including decorin (DCN), aggrecan (ACAN), fibromodulin (FMOD), α actin 2 (ACTA2), extracellular matrix protein 2 (ECM2), desmin (DES), endothelial cell specific molecule 1 (ESM1), and platelet/ endothelial cell adhesion molecule 1 (PECAM1), as well as inverse correlations of selected microRNA and mRNA expression in MMVP and FED groups. Our results provide evidence that distinct molecular mechanisms underlie MMVP and FED. Moreover, the microRNAs identified may be targets for the future development of diagnostic biomarkers and therapeutics. 相似文献
75.
Gupte R Patil R Liu J Wang Y Lee SC Fujiwara Y Fells J Bolen AL Emmons-Thompson K Yates CR Siddam A Panupinthu N Pham TC Baker DL Parrill AL Mills GB Tigyi G Miller DD 《ChemMedChem》2011,6(5):922-935
Autotaxin (ATX, NPP2) is a member of the nucleotide pyrophosphate phosphodiesterase enzyme family. ATX catalyzes the hydrolytic cleavage of lysophosphatidylcholine (LPC) by lysophospholipase D activity, which leads to generation of the growth‐factor‐like lipid mediator lysophosphatidic acid (LPA). ATX is highly upregulated in metastatic and chemotherapy‐resistant carcinomas and represents a potential target to mediate cancer invasion and metastasis. Herein we report the synthesis and pharmacological characterization of ATX inhibitors based on the 4‐tetradecanoylaminobenzylphosphonic acid scaffold, which was previously found to lack sufficient stability in cellular systems. The new 4‐substituted benzylphosphonic acid and 6‐substituted naphthalen‐2‐ylmethylphosphonic acid analogues block ATX activity with Ki values in the low micromolar to nanomolar range against FS3, LPC, and nucleotide substrates through a mixed‐mode inhibition mechanism. None of the compounds tested inhibit the activity of related enzymes (NPP6 and NPP7). In addition, the compounds were evaluated as agonists or antagonists of seven LPA receptor (LPAR) subtypes. Analogues 22 and 30 b , the two most potent ATX inhibitors, inhibit the invasion of MM1 hepatoma cells across murine mesothelial and human vascular endothelial monolayers in vitro in a dose‐dependent manner. The average terminal half‐life for compound 22 is 10±5.4 h and it causes a long‐lasting decrease in plasma LPA levels. Compounds 22 and 30 b significantly decrease lung metastasis of B16‐F10 syngeneic mouse melanoma in a post‐inoculation treatment paradigm. The 4‐substituted benzylphosphonic acids and 6‐substituted naphthalen‐2‐ylmethylphosphonic acids described herein represent new lead compounds that effectively inhibit the ATX–LPA–LPAR axis both in vitro and in vivo. 相似文献
76.
Romain Launay Elin Teppa Carla Martins Sophie S. Abby Fabien Pierrel Isabelle Andr Jrmy Esque 《International journal of molecular sciences》2022,23(18)
Ubiquinone (UQ) is a polyisoprenoid lipid found in the membranes of bacteria and eukaryotes. UQ has important roles, notably in respiratory metabolisms which sustain cellular bioenergetics. Most steps of UQ biosynthesis take place in the cytosol of E. coli within a multiprotein complex called the Ubi metabolon, that contains five enzymes and two accessory proteins, UbiJ and UbiK. The SCP2 domain of UbiJ was proposed to bind the hydrophobic polyisoprenoid tail of UQ biosynthetic intermediates in the Ubi metabolon. How the newly synthesised UQ might be released in the membrane is currently unknown. In this paper, we focused on better understanding the role of the UbiJ-UbiK2 heterotrimer forming part of the metabolon. Given the difficulties to gain functional insights using biophysical techniques, we applied a multiscale molecular modelling approach to study the UbiJ-UbiK2 heterotrimer. Our data show that UbiJ-UbiK2 interacts closely with the membrane and suggests possible pathways to enable the release of UQ into the membrane. This study highlights the UbiJ-UbiK2 complex as the likely interface between the membrane and the enzymes of the Ubi metabolon and supports that the heterotrimer is key to the biosynthesis of UQ8 and its release into the membrane of E. coli. 相似文献
77.
Sallis James F.; King Abby C.; Sirard John R.; Albright Cheryl L. 《Canadian Metallurgical Quarterly》2008,27(2):214
Reports an error in "Perceived environmental predictors of physical activity over 6 months in adults: Activity Counseling Trial" by James F. Sallis, Abby C. King, John R. Sirard and Cheryl L. Albright (Health Psychology, 2007[Nov], Vol 26[6], 701-709). One result in Table 2 was misinterpreted in the text. It was reported that men who responded "yes" to frequently seeing people being active in their neighborhoods did about 75 minutes more physical activity per week (p2007-16656-008.) Purpose: In the present study, the authors extend previous cross-sectional findings by using a prospective design to determine whether physical and social environmental characteristics predict physical activity over 6 months. Design: Inactive adults were recruited to the Activity Counseling Trial, a multicenter, randomized, controlled trial of physical activity intervention in primary care. Participants were 387 women and 474 men aged 35-75 years in 3 regions; 1/3 were minorities; 56% had some college education. Baseline perceived environmental variables were used to predict physical activity at 6 months, adjusting for experimental condition and other potential moderators. Measures: The validated 7-day physical activity recall interview was used to estimate minutes of moderate to vigorous physical activity. A standardized survey was used to measure social and physical environmental variables around the home and neighborhood. Results: Women reporting no unattended dogs and low crime in their neighborhoods and men reporting frequently seeing people being active in their neighborhoods did 50-75 more minutes of physical activity per week than did those with different environmental characteristics. Interactions of environmental variables with age group suggested that older adults may be more affected by environmental variables than are younger adults. Conclusions: Self-reported social and physical environmental variables were significantly related to moderate to vigorous physical activity among a diverse sample of adults living in 3 regions of the United States. These prospective findings strengthen the conclusion from previous cross-sectional studies that environmental variables are important correlates of physical activity. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
78.
McKee Sherry A.; Wall Anne-Marie; Hinson Riley E.; Goldstein Abby; Bissonnette Michelle 《Canadian Metallurgical Quarterly》2003,17(3):219
This study examined whether an implicit mood prime would differentially affect the accessibility of self-generated smoking expectancies in women. One hundred nine ever-smokers were randomly assigned to receive either a positive or negative musical mood induction or a no-music control condition. Participants self-generated smoking expectancies, and the 1st responses were categorized as positive reinforcement, negative reinforcement, or negative consequence expectancies. Overall, participants generated mood-congruent smoking expectancies, suggesting that affect may act as a conditioned stimulus that elicits expectations of positive and negative reinforcement of smoking behavior. In addition, negative reinforcement expectancies were more frequently generated in current versus past smokers. Results are consistent with a situational-specificity hypothesis and memory-based models of affect and expectancies. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
79.
Abby R Jennings Aimee M Morey Andrew J Guenthner Scott T Iacono 《Polymer International》2017,66(4):i-i
The cover image, by Abby R Jennings et al., of an artist's conception of the NASA “HIAD” which uses a variety of polymeric materials for construction is based on the Research Article Synthesis and characterization of siloxane‐based cyanate ester elastomers from readily available materials: a top‐down approach, DOI: 10.1002/pi.5276 . Photo Credit: NASA/JPL‐Caltech.
80.
Inman Arpana G.; Schlosser Lewis Z.; Ladany Nicholas; Howard Erin E.; Boyd Debra L.; Altman Abby N.; Stein Ellyn P. 《Canadian Metallurgical Quarterly》2011,5(3):149
Using a sample of 109 doctoral-level advisees, we examined the content of and reasons for advisee nondisclosures and the relationships between these variables and advising relationship and satisfaction. Discovery-oriented qualitative analyses revealed several themes related to content of advisee nondisclosures (e.g., self-efficacy) and reasons for these nondisclosures (e.g., fear of damaging advising relationship). Quantitative analyses revealed advisor–advisee rapport was related to advisee fears of being perceived as unprofessional, and identification with advisor was related to advisor's availability and dependability. Unclear advisor expectations, lack of support, and unavailability of the advisor were all related to satisfaction with the advising relationship. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献