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11.
Scientific publications tend to be forgotten quickly. A few works, however, are still cited 100 years and more after their publication. The author used bibliometric methods to compare "hits" (works noticed by the scientific community soon after their publication) with "missed signals" (works that went unnoticed until much later) by investigating 2 psychological journals founded in the 1890s: Zeitschrift für Psychologie and Psychological Review. All articles that were published in either of these journals up to 1920 and cited more than 25 times in the Web of Science up to the year 2000 were considered for inclusion in the analysis. It emerged that hits corresponded more closely to the focus of scientific attention at the time of publication than missed signals. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
12.
In 3 experiments, the authors investigated the effects of to-be-remembered (TBR) and intervening list length on free recall to determine whether selective rehearsal could explain the previous finding that recall was affected only by TBR list length. In Experiments 1 (covert rehearsal) and 2 (overt rehearsal), participants saw 5- and 20-word lists and had to recall the list prior to that last presented list. In Experiment 3, either 1 or 2 lists were presented, and recall of TBR list was postcued. Recall proportion decreased with increased TBR list length. Moreover, the authors found extended recency effects when recall was replotted by when words were last rehearsed (Experiments 2 and 3) and an effect of intervening list length when rehearsal was reduced (Experiment 3). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
13.
Semiconducting Carbon Nanotubes for Improved Efficiency and Thermal Stability of Polymer–Fullerene Solar Cells
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Teddy Salim Hang‐Woo Lee Lydia Helena Wong Zhenan Bao Yeng Ming Lam 《Advanced functional materials》2016,26(1):51-65
The effects of the incorporation of semiconducting single‐walled nanotubes (sc‐SWNTs) with high purity on the bulk heterojunction (BHJ) organic solar cell (OSC) based on regioregular poly(3‐hexylthiophene‐2,5‐diyl):[6,6]‐phenyl‐C61‐butyric acid methyl ester (rr‐P3HT:PCBM) are reported for the first time. The sc‐SWNTs induce the organization of the polymer phase, which is evident from the increase in crystallite size, the red‐shifted absorption characteristics and the enhanced hole mobility. By incorporating sc‐SWNTs, OSC with a power conversion efficiency (PCE) as high as 4% can be achieved, which is ≈8% higher than our best control device. A novel application of sc‐SWNTs in improving the thermal stability of BHJ OSCs is also demonstrated. After heating at 150 °C for 9 h, it is observed that the thermal stability of rr‐P3HT:PCBM devices improves by more than fivefold with inclusion of sc‐SWNTs. The thermal stability enhancement is attributed to a more suppressed phase separation, as shown by the remarkable decrease in the formation of sizeable crystals, which in turn can be the outcome of a more controlled crystallization of the blend materials on the nanotubes. 相似文献
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15.
Novel poly(3‐hydroxybutyrate) composite films containing bioactive glass nanoparticles for wound healing applications
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Lydia Francis Decheng Meng Ian C Locke Jonathan C Knowles Nicola Mordan Vehid Salih Aldo R Boccaccini Ipsita Roy 《Polymer International》2016,65(6):661-674
Bioactive glass is considered an ideal material for haemostasis as it releases Ca2+ ions upon hydration, which is required to support thrombosis. In this study the effects of the presence of nanoscaled bioactive glass (n‐BG) in poly(3‐hydroxybutyrate) (P(3HB)) microsphere films on the structural properties, thermal properties and biocompatibility of the films were studied. The n‐BG with a high surface area was also tested for its in vitro haemostatic efficacy and was found to be able to successfully reduce clot detection time. In an effort to study the effect of the roughness induced by the formation of hydroxyapatite on cellular functions such as cell adhesion, cell mobility and cell differentiation, the composite films were immersed in simulated body fluid for periods of 1, 3 and 7 days. From scanning electron microscopy images, the surface of the P(3HB)/n‐BG composite microsphere films appeared fairly uniform and smooth on day 1; however on day 3 and day 7 a rough and uneven surface was observed. The presence of hydroxyapatite on the composite microsphere films on day 3 and day 7 influenced the surface roughness of the films. However, when the P(3HB)/n‐BG composite microsphere films with enhanced surface roughness were tested for biocompatibility, reduced amounts of protein adsorption and cell adhesion were observed. This study thus revealed that there is an optimal surface roughness for the P(3HB) microsphere films for increased cell adhesion, beyond which it could be deleterious for cell adhesion and differentiation. © 2016 Society of Chemical Industry 相似文献
16.
N‐Benzyl‐4‐((heteroaryl)methyl)benzamides: A New Class of Direct NADH‐Dependent 2‐trans Enoyl–Acyl Carrier Protein Reductase (InhA) Inhibitors with Antitubercular Activity
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Ana Guardia Dr. Gulcin Gulten Dr. Raquel Fernandez Jesus Gómez Dr. Feng Wang Dr. Maire Convery Delia Blanco María Martínez Dr. Esther Pérez‐Herrán Marta Alonso Dr. Fátima Ortega Dr. Joaquín Rullás Dr. David Calvo Lydia Mata Dr. Robert Young Prof. James C. Sacchettini Dr. Alfonso Mendoza‐Losana Dr. Modesto Remuiñán Dr. Lluís Ballell Pages Dr. Julia Castro‐Pichel 《ChemMedChem》2016,11(7):687-701
Isoniazid (INH) remains one of the cornerstones of antitubercular chemotherapy for drug‐sensitive strains of M. tuberculosis bacteria. However, the increasing prevalence of multidrug‐resistant (MDR) and extensively drug‐resistant (XDR) strains containing mutations in the KatG enzyme, which is responsible for the activation of INH into its antitubercular form, have rendered this drug of little or no use in many cases of drug‐resistant tuberculosis. Presented herein is a novel family of antitubercular direct NADH‐dependent 2‐trans enoyl–acyl carrier protein reductase (InhA) inhibitors based on an N‐benzyl‐4‐((heteroaryl)methyl)benzamide template; unlike INH, these do not require prior activation by KatG. Given their direct InhA target engagement, these compounds should be able to circumvent KatG‐related resistance in the clinic. The lead molecules were shown to be potent inhibitors of InhA and showed activity against M. tuberculosis bacteria. This new family of inhibitors was found to be chemically tractable, as exemplified by the facile synthesis of analogues and the establishment of structure–activity relationships. Furthermore, a co‐crystal structure of the initial hit with the enzyme is disclosed, providing valuable information toward the design of new InhA inhibitors for the treatment of MDR/XDR tuberculosis. 相似文献
17.
A history of land clearance and riparian tree and wood management has resulted in limited riparian woodland and wood along British rivers. However, river management approaches are now being promoted that ‘work with natural processes’ to reduce flood risk through measures intended to restore, protect and emulate the natural function of catchments, rivers, estuaries and coasts. Wood has started to be reintroduced into river channels during river restoration and natural flood management activities, but this needs to be undertaken using appropriate quantities, locations and designs that mimic natural tree‐wood features. This paper reviews the knowledge that is needed to support wood reintroduction activities including (i) the characteristics of the riparian tree species and wood that are present; (ii) the importance of river size relative to that of trees and wood pieces; and (iii) the way trees, wood and geomorphic processes interact across rivers and floodplains of different energy and style. 相似文献
18.
Dr. Robert Kuhnert Dr. Lydia Kuhnert Dr. Menyhárt-B. Sárosi Sven George Dr. Dijana Draca Dr. Svetlana Paskas Dr. Bettina Hofmann Prof. Dr. Dieter Steinhilber Prof. Dr. Walther Honscha Prof. Dr. Sanja Mijatović Prof. Dr. Danijela Maksimović-Ivanić Prof. Dr. Evamarie Hey-Hawkins 《ChemMedChem》2022,17(1):e202100588
12-Lipoxygenase is crucial for tumour angiogenesis. 5,6,7-Trihydroxy-2-phenyl-4H-1-benzopyran-4-one (baicalein) is a suitable inhibitor for this enzyme but is rapidly metabolised in vivo. Thus, an improvement of the metabolic stability is necessary to enhance the therapeutic efficiency. An emerging approach to enhance metabolic stability of carbon-based pharmaceuticals is the use of metabolically stable, non-toxic boron clusters, such as dicarba-closo-dodecaborane(12)s (carboranes) as phenyl mimetics. Therefore, the unsubstituted phenyl ring of baicalein was replaced by meta-carborane, resulting in borcalein, the carborane analogue of baicalein. This substitution resulted in a decreased inhibitory activity toward 12-lipoxygenase, but led to increased toxicity in melanoma (A375, B16, B16F10) and colon cancer cell lines (SW480, HCT116, CT26CL25) with decreased tumour selectivity in comparison to baicalein. Surprisingly, borcalein displays a different mechanism of cytotoxicity with increased intracellular production of reactive oxygen species (ROS), reactive nitrogen species (RNS) and nitric oxide (NO). 相似文献
19.
Growth and characterization of l-phenylalanine nitric acid, a new organic nonlinear optical material
A new organic nonlinear optical material L-phenylalanine nitric acid [2C9H11NO2.H+. NO3−] (LPN), was synthesized in mixed solvent of deionised water and methanol and single crystals of LPN was grown by slow evaporation method. Transparent crystals upto 2.9 × 0.3 × 0.05 cm3 were obtained. The grown crystals have been subjected to powder X-ray diffraction studies to identify the crystalline nature. Single crystal X-ray diffractometer was utilized to measure unit cell parameters and to confirm the crystal structure. The modes of vibration of different molecular groups present in LPN were identified by FTIR spectral analysis. Transmission spectra reveals that the crystal has low UV cutoff of 295 nm and has a good transmittance in the entire visible region enabling its use in optical applications. Thermal properties of the crystals have been investigated using thermogravimetric (TG) and differential thermal analyses (DTA), which indicate that the material does not decompose before melting. The existence of second harmonic generation signals was observed using Nd:YAG laser with fundamental wavelength of 1064 nm. 相似文献
20.